{"id":9499,"date":"2026-09-21T23:11:33","date_gmt":"2026-09-21T14:11:33","guid":{"rendered":"https:\/\/now0930.pe.kr\/wordpress\/?p=9499"},"modified":"2026-09-21T23:28:51","modified_gmt":"2026-09-21T14:28:51","slug":"lessons-in-industrial-instrumentation-chapter-19","status":"publish","type":"post","link":"https:\/\/now0930.pe.kr\/wordpress\/lessons-in-industrial-instrumentation-chapter-19\/","title":{"rendered":"Lessons In Industrial Instrumentation, Chapter 19"},"content":{"rendered":"\n<div class=\"chapter19-wide\">\n\n  <h1>Chapter 19. Continuous Pressure Measurement<\/h1>\n\n  <div class=\"subtitle\">\n    \uc6a9\uc5b4 \uc815\uc758 \u2192 \uc6a9\uc5b4 \uac04 \uad00\uacc4 \u2192 \uc2a4\ud1a0\ub9ac \u2192 \ud604\uc7a5 \uc801\uc6a9\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>1. Chapter 19 \uc804\uccb4 \ud750\ub984<\/h2>\n\n  <div class=\"card\">\n\n    <div class=\"memory\">\n      <strong>\n        \uacf5\uc815\uc758 \uc555\ub825\uc744 \uc5b4\ub5bb\uac8c \uac10\uc9c0\ud558\uace0,\n        \uce21\uc815 \uac00\ub2a5\ud55c \ubb3c\ub9ac\ub7c9\uc73c\ub85c \ubcc0\ud658\ud558\uba70,\n        \uc804\uae30 \ub610\ub294 \uacf5\uc555 \uc2e0\ud638\ub85c \uc804\ub2ec\ud558\uace0,\n        \uc2e4\uc81c \ud604\uc7a5\uc5d0\uc11c \uc815\ud655\ud558\uace0 \uc548\uc804\ud558\uac8c \uce21\uc815\ud560 \uac83\uc778\uac00?\n      <\/strong>\n    <\/div>\n\n    <div class=\"flow\">\n      Pressure\n      \u2192 Liquid Height \/ Mechanical Force\n      \u2192 Electrical Quantity\n      \u2192 Pressure Transmitter\n      \u2192 Differential Pressure\n      \u2192 Inferential Measurement\n      \u2192 Field Accessories\n    <\/div>\n\n    <p>\n      Chapter 19\ub294 \uc555\ub825\uc758 \uae30\ubcf8 \uce21\uc815\uc5d0\uc11c \uc2dc\uc791\ud558\uc5ec\n      \uc13c\uc11c \uc6d0\ub9ac, transmitter, \ucc28\uc555 \uce21\uc815,\n      \uac04\uc811\uce21\uc815, \uc2e4\uc81c \uc124\uce58\uc640 \uc720\uc9c0\ubcf4\uc218 \ubb38\uc81c\ub85c \ud655\uc7a5\ub41c\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>2. \uc6a9\uc5b4 \uc815\ub9ac<\/h2>\n\n\n  <!-- ================================================= -->\n  <h3>2.1 Pressure<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      \uc555\ub825\uc740 \ub2e8\uc704 \uba74\uc801\uc5d0 \uc791\uc6a9\ud558\ub294 \ud798\uc774\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      P = F \/ A\n    <\/div>\n\n    <p>\n      \uc77c\uc815\ud55c \uba74\uc801\uc744 \uac00\uc9c4 sensing element\uc5d0 \uc555\ub825\uc774 \uc791\uc6a9\ud558\uba74\n      \uc555\ub825\uc744 \ud798\uc73c\ub85c \ubcc0\ud658\ud560 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      F = PA\n    <\/div>\n\n    <p>\n      \uc555\ub825\uc740 \uadf8 \uc790\uccb4\ub85c \uc911\uc694\ud55c process variable\uc774\uc9c0\ub9cc,\n      \ub2e4\ub978 \uacf5\uc815\ubcc0\uc218\ub97c \uac04\uc811\uc801\uc73c\ub85c \uacc4\uc0b0\ud558\ub294 \ub370\ub3c4 \uc0ac\uc6a9\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      P = \u03c1gh\n    <\/div>\n\n    <div class=\"formula\">\n      Q \u221d \u221a\u0394P\n    <\/div>\n\n    <p>\n      \ub530\ub77c\uc11c pressure measurement\ub294\n      liquid level\uacfc fluid flow measurement\ub85c \ud655\uc7a5\ub420 \uc218 \uc788\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.2 Manometer<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Manometer\ub294 \uc555\ub825\uc744 \uc561\uc8fc\uc758 \ub192\uc774\ub85c \ubcc0\ud658\ud558\uc5ec \uce21\uc815\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Pressure \u2192 Liquid Column Height\n    <\/div>\n\n    <div class=\"formula\">\n      P = \u03c1gh\n    <\/div>\n\n\n    <h4>Gauge Pressure<\/h4>\n\n    <p>\n      \ud55c\ucabd pressure port\ub97c atmosphere\uc5d0 \uac1c\ubc29\ud55c\ub2e4.\n      \ub530\ub77c\uc11c process pressure\uc640 atmospheric pressure\uc758 \ucc28\uc774\ub97c \uce21\uc815\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      Pg = Pprocess \u2212 Patm\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>Gauge Pressure = Atmospheric Pressure \uae30\uc900<\/strong>\n    <\/div>\n\n\n    <h4>Differential Pressure<\/h4>\n\n    <p>\n      \ub450 pressure port\ub97c \ubaa8\ub450 \uc0ac\uc6a9\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      \u0394P = PH \u2212 PL\n    <\/div>\n\n    <p>\n      \ub530\ub77c\uc11c \ub450 \uc9c0\uc810 \uc0ac\uc774\uc758 \uc555\ub825\ucc28\ub97c \uc9c1\uc811 \uce21\uc815\ud55c\ub2e4.\n    <\/p>\n\n\n    <h4>Absolute Pressure<\/h4>\n\n    <p>\n      \ud55c\ucabd pressure port\ub97c sealed vacuum chamber\uc5d0 \uc5f0\uacb0\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"memory\">\n      <strong>Absolute Pressure = Vacuum \uae30\uc900<\/strong>\n    <\/div>\n\n    <p>\n      Mercury barometer\uac00 \ub300\ud45c\uc801\uc778 \uc608\uc774\ub2e4.\n    <\/p>\n\n\n    <h4>Well-type Manometer<\/h4>\n\n    <p>\n      Well\uc758 \ub2e8\uba74\uc801\uc744 transparent tube\ubcf4\ub2e4 \ub9e4\uc6b0 \ud06c\uac8c \ub9cc\ub4e0\ub2e4.\n      \ub530\ub77c\uc11c well \ub0b4\ubd80\uc758 \uc561\uba74 \ubcc0\ud654\ub294 \ub9e4\uc6b0 \uc791\ub2e4.\n    <\/p>\n\n    <p>\n      \uadf8 \uacb0\uacfc \ub450 \uc561\uc8fc\uc758 \ub192\uc774\ucc28\ub97c \ubaa8\ub450 \uc77d\uc9c0 \uc54a\uace0\n      \ud55c\ucabd \uc561\uc8fc\uc758 \ub192\uc774\ub9cc \uc77d\uc744 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <div class=\"memory\">\n      <strong>Single-point Reading<\/strong>\n    <\/div>\n\n    <p>\n      Well \ucabd\uc758 \uc561\uba74 \ubcc0\ud654\uac00 \ubb34\uc2dc\ud560 \uc218 \uc5c6\uc744 \uacbd\uc6b0\uc5d0\ub294\n      scale division\uc744 \ubcf4\uc815\ud558\uc5ec \uc624\ucc28\ub97c \ubcf4\uc0c1\ud55c\ub2e4.\n    <\/p>\n\n\n    <h4>Inclined Manometer<\/h4>\n\n    <p>\n      Manometer tube\ub97c \uae30\uc6b8\uc774\uba74\n      \ub3d9\uc77c\ud55c \uc218\uc9c1 \ub192\uc774 \ubcc0\ud654\uc5d0 \ub300\ud574\n      \uc561\uccb4\uac00 tube\ub97c \ub530\ub77c \ub354 \uae34 \uac70\ub9ac\ub97c \uc774\ub3d9\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Inclination\n      \u2192 Travel Distance \uc99d\uac00\n      \u2192 Sensitivity \uc99d\uac00\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.3 Mechanical Pressure Elements<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      \uc555\ub825\uc744 \uae30\uacc4\uc801 \ud798 \ub610\ub294 \ubcc0\ud615\uc73c\ub85c \ubc14\uafb8\uc5b4 \uce21\uc815\ud55c\ub2e4.\n    <\/p>\n\n    <ul>\n      <li>Bourdon tube<\/li>\n      <li>Diaphragm<\/li>\n      <li>Bellows<\/li>\n    <\/ul>\n\n    <div class=\"formula\">\n      F = PA\n    <\/div>\n\n    <div class=\"flow\">\n      Pressure\n      \u2192 Force\n      \u2192 Mechanical Deformation\n    <\/div>\n\n    <p>\n      Mechanical pressure element\ub294\n      \uc624\ub7ab\ub3d9\uc548 \uc0b0\uc5c5\ud604\uc7a5\uc5d0\uc11c \uc0ac\uc6a9\ub418\uc5b4 \uc628\n      \uacac\uace0\ud558\uace0 \uac80\uc99d\ub41c \uce21\uc815 \ubc29\uc2dd\uc774\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.4 Electrical Pressure Elements<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      \uc555\ub825\uc5d0 \uc758\ud574 \ubc1c\uc0dd\ud55c \uae30\uacc4\uc801 \ubcc0\ud654\ub97c\n      \uc804\uae30\uc801\uc73c\ub85c \uce21\uc815 \uac00\ub2a5\ud55c \uac12\uc73c\ub85c \ubcc0\ud658\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"table-wrap\">\n\n      <table>\n\n        <thead>\n          <tr>\n            <th>Sensor<\/th>\n            <th>\uc555\ub825\uc774 \ubcc0\ud654\uc2dc\ud0a4\ub294 \uac83<\/th>\n            <th>\ucd5c\uc885 \uce21\uc815\ub7c9<\/th>\n          <\/tr>\n        <\/thead>\n\n        <tbody>\n\n          <tr>\n            <td>Piezoresistive \/ Strain Gauge<\/td>\n            <td>Mechanical strain<\/td>\n            <td>Resistance R<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Differential Capacitance<\/td>\n            <td>Diaphragm position<\/td>\n            <td>Capacitance C<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Resonant Element<\/td>\n            <td>Tension \/ mechanical state<\/td>\n            <td>Resonant frequency f<\/td>\n          <\/tr>\n\n        <\/tbody>\n\n      <\/table>\n\n    <\/div>\n\n    <div class=\"flow\">\n      Pressure \u2192 R, C, f\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.5 Piezoresistive \/ Strain-gauge Sensor<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      \uc555\ub825\uc774 diaphragm \ub4f1\uc5d0 \uc791\uc6a9\ud558\uba74\n      mechanical strain\uc774 \ubc1c\uc0dd\ud55c\ub2e4.\n    <\/p>\n\n    <p>\n      \uc774 strain\uc5d0 \uc758\ud574 sensor\uc758 electrical resistance\uac00 \ubcc0\ud654\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Pressure\n      \u2192 Mechanical Strain\n      \u2192 Resistance Change\n      \u2192 Electrical Signal\n    <\/div>\n\n    <p>\n      \uae08\uc18d \ub610\ub294 semiconductor \uc7ac\ub8cc\ub97c \uc0ac\uc6a9\ud560 \uc218 \uc788\ub2e4.\n      Semiconductor\ub294 \uc791\uc740 \ubcc0\ud615\uc5d0\ub3c4\n      \uc0c1\ub300\uc801\uc73c\ub85c \ud070 \uc800\ud56d \ubcc0\ud654\ub97c \uc5bb\uc744 \uc218 \uc788\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.6 Differential Capacitance Sensor<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      \ub450 \uc555\ub825\uc758 \ucc28\uc774\uac00 sensing diaphragm\uc5d0 \ud798\uc744 \uac00\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      F = (PH \u2212 PL)A\n    <\/div>\n\n    <p>\n      Diaphragm\uc774 \ud55c\ucabd\uc73c\ub85c \uc774\ub3d9\ud558\uba74\n      \uc591\ucabd capacitance\uac00 \uc11c\ub85c \ubc18\ub300 \ubc29\ud5a5\uc73c\ub85c \ubcc0\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      C = \u03b5A \/ d\n    <\/div>\n\n    <div class=\"formula\">\n      d1 \u2193 \u2192 C1 \u2191\n    <\/div>\n\n    <div class=\"formula\">\n      d2 \u2191 \u2192 C2 \u2193\n    <\/div>\n\n    <p>\n      Sensor circuit\uc740 high-frequency AC excitation\uc744 \uc774\uc6a9\ud558\uc5ec\n      \ub450 capacitance\uc758 \ucc28\uc774\ub97c \uac80\ucd9c\ud55c\ub2e4.\n    <\/p>\n\n    <p>\n      \uadf8 \ucc28\uc774\ub97c DC signal\ub85c \ubcc0\ud658\ud558\uc5ec\n      \ucd5c\uc885 pressure signal\uc744 \ub9cc\ub4e0\ub2e4.\n    <\/p>\n\n\n    <h4>Isolating Diaphragm\uacfc Fill Fluid<\/h4>\n\n    <div class=\"flow\">\n      Process Pressure\n      \u2192 Isolating Diaphragm\n      \u2192 Fill Fluid\n      \u2192 Sensing Diaphragm\n    <\/div>\n\n    <p>\n      \uc774 \uad6c\uc870\uc758 \ud575\uc2ec \ubaa9\uc801\uc740\n      \uce21\uc815 \uae30\ub2a5\uacfc overpressure protection \uae30\ub2a5\uc744 \ubd84\ub9ac\ud558\ub294 \uac83\uc774\ub2e4.\n    <\/p>\n\n    <ul>\n      <li>Sensing diaphragm: capacitance \uce21\uc815<\/li>\n      <li>Isolating diaphragm: process pressure \uc804\ub2ec<\/li>\n      <li>Fill fluid: diaphragm \uc0ac\uc774\uc758 pressure \uc804\ub2ec<\/li>\n      <li>Solid frame: isolating diaphragm\uc758 \uacfc\ub3c4\ud55c \uc774\ub3d9 \uc81c\ud55c<\/li>\n    <\/ul>\n\n    <p>\n      Capacitance sensing diaphragm\uc740\n      \uc815\uc0c1\uc801\uc778 \uce21\uc815\uc744 \uc704\ud574 conductive frame\uc5d0 \uc811\ucd09\ud558\uc9c0 \uc54a\uc544\uc57c \ud55c\ub2e4.\n    <\/p>\n\n    <p>\n      \uadf8\ub7ec\ub098 overpressure protection\uc744 \uc704\ud574\uc11c\ub294\n      diaphragm\uc758 \uc774\ub3d9\uc744 \uc81c\ud55c\ud560 solid backstop\uc774 \ud544\uc694\ud558\ub2e4.\n    <\/p>\n\n    <p>\n      \ub530\ub77c\uc11c \ub450 \uae30\ub2a5\uc744 \ud558\ub098\uc758 diaphragm\uc5d0 \ub9e1\uae30\uc9c0 \uc54a\uace0 \ubd84\ub9ac\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"memory\">\n      <strong>\n        Sensing Diaphragm = Measurement<br>\n        Isolating Diaphragm + Frame = Overpressure Protection\n      <\/strong>\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.7 Resonant Element Sensor<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Resonant element\uc758 tension\uc774 \uc99d\uac00\ud558\uba74\n      natural frequency\uac00 \uc99d\uac00\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      f = 1\/(2L) \u00d7 \u221a(FT \/ \u03bc)\n    <\/div>\n\n    <ul>\n      <li>f: Fundamental resonant frequency<\/li>\n      <li>L: String length<\/li>\n      <li>FT: String tension<\/li>\n      <li>\u03bc: Unit mass<\/li>\n    <\/ul>\n\n    <div class=\"flow\">\n      Pressure\n      \u2192 Force\n      \u2192 Tension\n      \u2192 Resonant Frequency\n    <\/div>\n\n    <p>\n      Oscillator circuit\uc740 resonant element\ub97c \uacc4\uc18d \uc9c4\ub3d9\uc2dc\ud0a4\uace0,\n      detector\ub294 resonant frequency\ub97c \uce21\uc815\ud55c\ub2e4.\n    <\/p>\n\n    <p>\n      \uc911\uc694\ud55c \uc810\uc740 force\uc640 frequency\uac00 \uc120\ud615\uad00\uacc4\uac00 \uc544\ub2c8\ub77c\ub294 \uac83\uc774\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      f \u221d \u221aFT\n    <\/div>\n\n    <p>\n      \ub530\ub77c\uc11c transmitter \ub0b4\ubd80\uc5d0\uc11c\n      electronic characterizing function\uc744 \uc774\uc6a9\ud574\n      frequency signal\uc744 linearize\ud574\uc57c \ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Frequency Measurement\n      \u2192 Linearization\n      \u2192 Pressure\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.8 Force-Balance Pressure Transmitter<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Force-balance \ubc29\uc2dd\uc740\n      process pressure\uac00 \ub9cc\ub4e0 \ud798\uc744\n      \ub2e4\ub978 \uc870\uc808 \uac00\ub2a5\ud55c \ud798\uc73c\ub85c \uc0c1\uc1c4\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      Fsensed = Fbalance\n    <\/div>\n\n    <div class=\"formula\">\n      Fsensed = \u0394P \u00d7 A\n    <\/div>\n\n\n    <h4>Force Balance\ub97c \uc5b4\ub5bb\uac8c \uac80\ucd9c\ud558\ub294\uac00?<\/h4>\n\n    <p>\n      Force \uc790\uccb4\ub97c \uc9c1\uc811 \ube44\uad50\ud558\ub294 \uac83\uc774 \uc544\ub2c8\ub2e4.\n    <\/p>\n\n    <p>\n      \ub450 \ud798\uc774 \ub2e4\ub974\uba74 force bar\uac00\n      \uae30\uc900 \uc704\uce58\uc5d0\uc11c \uc57d\uac04 \ubc97\uc5b4\ub09c\ub2e4.\n    <\/p>\n\n    <div class=\"memory\">\n      <strong>\n        Force \uc790\uccb4\uac00 \uc544\ub2c8\ub77c Position Error\ub97c \uac80\ucd9c\ud55c\ub2e4.\n      <\/strong>\n    <\/div>\n\n    <p>\n      Position error\uac00 0\uc73c\ub85c \ub3cc\uc544\uc624\uba74\n      \ub450 force\uac00 balance\ub418\uc5c8\ub2e4\uace0 \ud310\ub2e8\ud55c\ub2e4.\n    <\/p>\n\n\n    <h4>Pneumatic Force Balance<\/h4>\n\n    <div class=\"flow\">\n      Force Bar Displacement\n      \u2192 Baffle-Nozzle\n      \u2192 Relay\n      \u2192 Bellows Pressure\n      \u2192 Counter Force\n    <\/div>\n\n    <p>\n      Baffle-nozzle\uc740 \uc808\ub300 \uc704\uce58\ub97c \uce21\uc815\ud558\ub294 \uc7a5\uce58\ub77c\uae30\ubcf4\ub2e4\n      balance position\uc5d0\uc11c \ubc97\uc5b4\ub0ac\ub294\uc9c0 \uac10\uc9c0\ud558\ub294\n      null detector \uc5ed\ud560\uc744 \ud55c\ub2e4.\n    <\/p>\n\n\n    <h4>Electronic Force Balance<\/h4>\n\n    <div class=\"flow\">\n      Force Bar\n      \u2192 Balance Sensor\n      \u2192 Amplifier\n      \u2192 Force Coil\n      \u2192 Counter Force\n    <\/div>\n\n    <div class=\"formula\">\n      Fbalance \u221d I\n    <\/div>\n\n    <p>\n      Equilibrium\uc5d0\uc11c force coil\uc5d0 \ud750\ub974\ub294 current\uac00\n      pressure\ub97c \ub098\ud0c0\ub0b8\ub2e4.\n    <\/p>\n\n\n    <h4>\uc7a5\uc810<\/h4>\n\n    <ul>\n      <li>\ub192\uc740 \uc120\ud615\uc131<\/li>\n      <li>Sensing element\uc758 motion\uc774 \ub9e4\uc6b0 \uc791\uc74c<\/li>\n      <li>Spring characteristic \ubcc0\ud654\uc758 \uc601\ud5a5\uc774 \uc791\uc74c<\/li>\n      <li>Metal fatigue \uc601\ud5a5 \uac10\uc18c<\/li>\n    <\/ul>\n\n\n    <h4>\ub2e8\uc810<\/h4>\n\n    <ul>\n      <li>\uad6c\uc870\uac00 \ud06c\uace0 \ubcf5\uc7a1\ud568<\/li>\n      <li>External vibration\uc5d0 \ubbfc\uac10\ud568<\/li>\n      <li>Vibration\uc774 inertial force\uac00 \ub418\uc5b4 output noise \ubc1c\uc0dd<\/li>\n      <li>Electronic \ubc29\uc2dd\uc740 balancing force \uc0dd\uc131\uc744 \uc704\ud574 \ube44\uad50\uc801 \ud070 power \ud544\uc694<\/li>\n      <li>Intrinsic safety \uad6c\ud604\uc5d0 \ubd88\ub9ac\ud560 \uc218 \uc788\uc74c<\/li>\n    <\/ul>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.9 Differential Pressure Transmitter<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      DP transmitter\ub294 \ub450 pressure\uc758 \ucc28\uc774\ub97c \uce21\uc815\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      \u0394P = PH \u2212 PL\n    <\/div>\n\n    <ul>\n      <li>H: High-pressure side<\/li>\n      <li>L: Low-pressure side<\/li>\n    <\/ul>\n\n    <p>\n      \ud575\uc2ec\uc740 \ub450 \uc785\ub825\uc5d0 \uacf5\ud1b5\uc73c\ub85c \uc874\uc7ac\ud558\ub294 pressure\ubcf4\ub2e4\n      \ub450 pressure\uc758 \ucc28\uc774\uc5d0 \ubc18\uc751\ud558\ub294 \uac83\uc774\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      Vout = A(V1 \u2212 V2)\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>\n        Common Component\ubcf4\ub2e4 Difference\ub97c \uce21\uc815\ud55c\ub2e4.\n      <\/strong>\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>2.10 Inferential Measurement<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Pressure \ub610\ub294 differential pressure\ub97c \uc9c1\uc811 \uce21\uc815\ud55c \ub4a4\n      \ubb3c\ub9ac \uad00\uacc4\uc2dd\uc744 \uc774\uc6a9\ud558\uc5ec\n      \ub2e4\ub978 process variable\uc744 \uacc4\uc0b0\ud560 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <p>\n      \uc774\ub97c inferential measurement\ub77c\uace0 \ud55c\ub2e4.\n    <\/p>\n\n\n    <h4>Liquid Level<\/h4>\n\n    <div class=\"formula\">\n      P = \u03c1gh\n    <\/div>\n\n    <div class=\"formula\">\n      h = P \/ (\u03c1g)\n    <\/div>\n\n    <div class=\"flow\">\n      Pressure \u2192 Liquid Level\n    <\/div>\n\n\n    <h4>Fluid Flow<\/h4>\n\n    <div class=\"formula\">\n      Q \u221d \u221a\u0394P\n    <\/div>\n\n    <div class=\"flow\">\n      Differential Pressure \u2192 Fluid Flow\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>\n        Pressure\n        \u2192 Differential Pressure\n        \u2192 Inferential Measurement\n      <\/strong>\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>3. Pressure Sensor Accessories<\/h2>\n\n  <div class=\"card\">\n\n    <p>\n      \uc2e4\uc81c \uc0b0\uc5c5\ud604\uc7a5\uc5d0\uc11c\ub294\n      pressure transmitter \uc790\uccb4\ub9cc \uc815\ud655\ud558\ub2e4\uace0 \ud574\uc11c\n      \uc804\uccb4 \uce21\uc815\uc774 \uc815\ud655\ud55c \uac83\uc740 \uc544\ub2c8\ub2e4.\n    <\/p>\n\n    <ul>\n      <li>Pulsation<\/li>\n      <li>Residual pressure<\/li>\n      <li>Trapped gas<\/li>\n      <li>Condensed liquid<\/li>\n      <li>High temperature<\/li>\n      <li>Corrosion<\/li>\n      <li>Plugging<\/li>\n      <li>Vibration<\/li>\n      <li>Freezing<\/li>\n    <\/ul>\n\n    <div class=\"memory\">\n      <strong>\n        Accessories =\n        Pressure Sensor\uac00 \uc815\uc0c1\uc801\uc73c\ub85c \uce21\uc815\ud560 \uc218 \uc788\ub294 \ud658\uacbd\uc744 \ub9cc\ub4dc\ub294 \uc7a5\uce58\n      <\/strong>\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>3.1 Valve Manifold<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      DP transmitter\uc758 H\uc640 L pressure port\ub97c\n      process impulse line\uc5d0 \uc5f0\uacb0\ud558\uace0,\n      transmitter\ub97c process\uc5d0\uc11c \uaca9\ub9ac\ud558\uba70,\n      H\uc640 L pressure\ub97c equalize\ud558\uae30 \uc704\ud574 \uc0ac\uc6a9\ud55c\ub2e4.\n    <\/p>\n\n    <p>\n      Standard 3-valve manifold\ub294 \ub2e4\uc74c \uc138 valve\ub85c \uad6c\uc131\ub41c\ub2e4.\n    <\/p>\n\n    <ul>\n      <li>High-side block valve<\/li>\n      <li>Low-side block valve<\/li>\n      <li>Equalizing valve<\/li>\n    <\/ul>\n\n    <div class=\"warning\">\n      <strong>\n        Standard 3-valve manifold \uc790\uccb4\uc5d0\ub294 bleed valve\uac00 \ud3ec\ud568\ub418\uc9c0 \uc54a\ub294\ub2e4.\n        H\uce21\uacfc L\uce21 bleed fitting\uc740 transmitter flange\uc5d0 \ubcc4\ub3c4\ub85c \uc124\uce58\ub420 \uc218 \uc788\ub2e4.\n      <\/strong>\n    <\/div>\n\n\n    <h4>Normal Operation<\/h4>\n\n    <div class=\"table-wrap\">\n\n      <table>\n\n        <thead>\n          <tr>\n            <th>Valve \/ Fitting<\/th>\n            <th>Normal \uc0c1\ud0dc<\/th>\n          <\/tr>\n        <\/thead>\n\n        <tbody>\n\n          <tr>\n            <td>High-side block<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Low-side block<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Equalizing<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>High-side bleed<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Low-side bleed<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n        <\/tbody>\n\n      <\/table>\n\n    <\/div>\n\n    <p>\n      \ub530\ub77c\uc11c H\uc640 L\uc758 pressure\uac00 \uac01\uac01 transmitter\uc5d0 \uc804\ub2ec\ub418\uace0,\n      \uc815\uc0c1\uc801\uc778 differential pressure\uac00 \ud615\uc131\ub41c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      \u0394P = PH \u2212 PL\n    <\/div>\n\n\n    <h4>Normal \u2192 Removed from Service<\/h4>\n\n    <ol>\n\n      <li>\n        <strong>High-side block valve Close<\/strong><br>\n        H\uce21 process pressure\ub97c \ucc28\ub2e8\ud55c\ub2e4.\n      <\/li>\n\n      <li>\n        <strong>Equalizing valve Open<\/strong><br>\n        H\uc640 L chamber\ub97c \uc5f0\uacb0\ud558\uc5ec\n        transmitter \uc591\ub2e8\uc758 differential pressure\ub97c \uc81c\uac70\ud55c\ub2e4.\n      <\/li>\n\n      <li>\n        <strong>Low-side block valve Close<\/strong><br>\n        H\uc640 L \ubaa8\ub450 process\ub85c\ubd80\ud130 \uaca9\ub9ac\ud55c\ub2e4.\n      <\/li>\n\n      <li>\n        <strong>High \/ Low Bleed Open<\/strong><br>\n        \ub0b4\ubd80 residual pressure\ub97c \uc81c\uac70\ud55c\ub2e4.\n      <\/li>\n\n    <\/ol>\n\n    <div class=\"sequence\">\n      Normal\n      \u2192 H Close\n      \u2192 Equalize Open\n      \u2192 L Close\n      \u2192 H\/L Bleed Open\n      \u2192 Removed\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>HC \u2192 EO \u2192 LC \u2192 BO<\/strong>\n    <\/div>\n\n\n    <h4>Removed \uc0c1\ud0dc<\/h4>\n\n    <div class=\"table-wrap\">\n\n      <table>\n\n        <thead>\n          <tr>\n            <th>Valve \/ Fitting<\/th>\n            <th>Removed \uc0c1\ud0dc<\/th>\n          <\/tr>\n        <\/thead>\n\n        <tbody>\n\n          <tr>\n            <td>High-side block<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Low-side block<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Equalizing<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n          <tr>\n            <td>High-side bleed<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Low-side bleed<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n        <\/tbody>\n\n      <\/table>\n\n    <\/div>\n\n\n    <h4>Removed from Service \u2192 Normal<\/h4>\n\n    <p>\n      \uc815\uc0c1 \uc6b4\uc804\uc73c\ub85c \ubcf5\uadc0\ud560 \ub54c\ub294\n      \uc81c\uac70 \uacfc\uc815\uc758 \uc5ed\uc21c\uc73c\ub85c \uc870\uc791\ud55c\ub2e4.\n    <\/p>\n\n    <ol>\n\n      <li>\n        <strong>High \/ Low Bleed Close<\/strong><br>\n        \ub300\uae30\ub85c \uc5f4\ub9b0 \uacbd\ub85c\ub97c \uba3c\uc800 \ucc28\ub2e8\ud55c\ub2e4.\n      <\/li>\n\n      <li>\n        <strong>Low-side block valve Open<\/strong><br>\n        L\uce21 process pressure\ub97c transmitter\uc5d0 \uc804\ub2ec\ud55c\ub2e4.\n      <\/li>\n\n      <li>\n        <strong>Equalizing valve Close<\/strong><br>\n        H\uc640 L chamber\ub97c \uc11c\ub85c \ubd84\ub9ac\ud55c\ub2e4.\n      <\/li>\n\n      <li>\n        <strong>High-side block valve Open<\/strong><br>\n        \uc815\uc0c1\uc801\uc778 differential pressure \uce21\uc815\uc744 \uc2dc\uc791\ud55c\ub2e4.\n      <\/li>\n\n    <\/ol>\n\n    <div class=\"sequence\">\n      Removed\n      \u2192 H\/L Bleed Close\n      \u2192 L Open\n      \u2192 Equalize Close\n      \u2192 H Open\n      \u2192 Normal\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>BC \u2192 LO \u2192 EC \u2192 HO<\/strong>\n    <\/div>\n\n    <p>\n      \uc5ec\uae30\uc11c H = High-side, L = Low-side,\n      E = Equalizing, B = High\/Low Bleed,\n      O = Open, C = Closed\uc774\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>3.2 Bleed \/ Vent Fitting<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Bleed fitting\uc740 transmitter \ub610\ub294 pressure chamber \ub0b4\ubd80\uc758\n      \uc555\ub825\uc744 atmosphere\ub85c \ubc29\ucd9c\ud55c\ub2e4.\n    <\/p>\n\n    <p>\uc8fc\uc694 \ubaa9\uc801\uc740 \ub2e4\uc74c\uacfc \uac19\ub2e4.<\/p>\n\n    <ol>\n      <li>\uc720\uc9c0\ubcf4\uc218 \uc804 residual pressure \uc81c\uac70<\/li>\n      <li>Zero-energy state \ud615\uc131<\/li>\n      <li>Liquid process\uc758 trapped gas \uc81c\uac70<\/li>\n      <li>Gas process\uc758 condensed liquid \uc81c\uac70<\/li>\n      <li>Test pressure connection \uc81c\uacf5<\/li>\n    <\/ol>\n\n    <div class=\"flow\">\n      Isolation + Bleeding \u2192 Zero-Energy State\n    <\/div>\n\n\n    <h4>Bleed Fitting\uc758 \uc124\uce58 \uc704\uce58<\/h4>\n\n    <div class=\"grid-2\">\n\n      <div class=\"memory\">\n        <strong>Liquid Process<\/strong><br><br>\n        Gas\ub294 \uc704\ucabd\uc5d0 \ubaa8\uc778\ub2e4.<br>\n        \u2192 Upper Bleed\n      <\/div>\n\n      <div class=\"memory\">\n        <strong>Gas Process<\/strong><br><br>\n        Condensed Liquid\ub294 \uc544\ub798\ucabd\uc5d0 \ubaa8\uc778\ub2e4.<br>\n        \u2192 Lower Bleed\n      <\/div>\n\n    <\/div>\n\n\n    <h4>Stinger<\/h4>\n\n    <p>\n      Bleed plug\ub97c \uc644\uc804\ud788 \uc81c\uac70\ud558\uba74\n      bleed port\ub97c test pressure \uc5f0\uacb0\uc6a9 port\ub85c \uc0ac\uc6a9\ud560 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <p>\n      Bleed port adapter \ub610\ub294\n      DP transmitter calibration fitting\uc744\n      \ud604\uc7a5\uc5d0\uc11c \ud754\ud788 <strong>stinger<\/strong>\ub77c\uace0 \ubd80\ub978\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Hand Pump\n      \u2192 Test Gauge\n      \u2192 Stinger\n      \u2192 DP Transmitter\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>3.3 DP Transmitter Pressure Test<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Pressure test \uc911\uc5d0\ub294 transmitter\ub97c process\uc5d0\uc11c \uaca9\ub9ac\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"table-wrap\">\n\n      <table>\n\n        <thead>\n          <tr>\n            <th>Valve \/ Fitting<\/th>\n            <th>Under Test \uc0c1\ud0dc<\/th>\n          <\/tr>\n        <\/thead>\n\n        <tbody>\n\n          <tr>\n            <td>High-side block<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Low-side block<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Equalizing<\/td>\n            <td>Closed<\/td>\n          <\/tr>\n\n          <tr>\n            <td>High-side bleed<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n          <tr>\n            <td>Low-side bleed<\/td>\n            <td>Open<\/td>\n          <\/tr>\n\n        <\/tbody>\n\n      <\/table>\n\n    <\/div>\n\n    <p>\n      H\uce21\uc5d0\ub294 hand pump\uc640 test gauge\ub97c \uc5f0\uacb0\ud55c\ub2e4.\n      L\uce21\uc740 vent\ub418\uc5b4 reference pressure\ub97c \ud615\uc131\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"warning\">\n      <strong>\n        Equalizing valve\uac00 \uc5f4\ub9b0 \uc0c1\ud0dc\ub77c\uba74\n        PH = PL\uc774 \ub418\uc5b4 \u0394P = 0\uc774\ubbc0\ub85c\n        differential pressure test\ub97c \uc218\ud589\ud560 \uc218 \uc5c6\ub2e4.\n      <\/strong>\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>3.4 Pressure Pulsation Damping<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      Pump \ub610\ub294 compressor\uc5d0\uc11c\ub294\n      pressure\uac00 \uc9e7\uc740 \uc8fc\uae30\ub85c \ubc18\ubcf5 \ubcc0\ud654\ud560 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <p>\n      \uc774\ub97c pressure pulsation\uc774\ub77c\uace0 \ud55c\ub2e4.\n    <\/p>\n\n    <p>Pulsation\uc740 \ub2e4\uc74c \ubb38\uc81c\ub97c \ubc1c\uc0dd\uc2dc\ud0a8\ub2e4.<\/p>\n\n    <ul>\n      <li>Gauge pointer vibration<\/li>\n      <li>Measurement fluctuation<\/li>\n      <li>Mechanical sensing element fatigue<\/li>\n      <li>Instrument life \uac10\uc18c<\/li>\n    <\/ul>\n\n    <p>\n      Snubber \ub610\ub294 damper\ub294\n      \uc720\uccb4 \uc774\ub3d9\uc5d0 restriction\uc744 \ub9cc\ub4e4\uc5b4\n      \ube60\ub978 pressure \ubcc0\ud654\uac00 \uadf8\ub300\ub85c \uc804\ub2ec\ub418\uc9c0 \uc54a\uac8c \ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Rapid Pressure Pulsation\n      \u2192 Restriction\n      \u2192 Smoothed Pressure\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>\n        Signal \uad00\uc810\uc5d0\uc11c\ub294 Low-Pass Filter\uc640 \uc720\uc0ac\ud558\uac8c \uc774\ud574\ud560 \uc218 \uc788\ub2e4.\n      <\/strong>\n    <\/div>\n\n    <div class=\"warning\">\n      Damping\uc774 \ub108\ubb34 \ud06c\uba74 \uc2e4\uc81c process pressure \ubcc0\ud654\uae4c\uc9c0 \ub290\ub9ac\uac8c \uc804\ub2ec\ub41c\ub2e4.\n      \ub530\ub77c\uc11c Pulsation Reduction\uacfc Response Speed \uc0ac\uc774\uc5d0 trade-off\uac00 \uc788\ub2e4.\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h3>3.5 Isolating Diaphragm \/ Process Isolation<\/h3>\n\n  <div class=\"card\">\n\n    <p>\n      \uc624\uc5fc\uc131 \ub610\ub294 \ubd80\uc2dd\uc131 process fluid\uac00\n      pressure sensor \ub0b4\ubd80\uc5d0 \uc9c1\uc811 \uc811\ucd09\ud558\ub294 \uac83\uc744 \ud53c\ud574\uc57c \ud560 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Process Fluid\n      \u2192 Isolating Diaphragm\n      \u2192 Fill Fluid\n      \u2192 Pressure Sensor\n    <\/div>\n\n    <div class=\"memory\">\n      <strong>\n        Process Fluid\ub294 \ucc28\ub2e8\ud558\uace0 Pressure\ub294 \uc804\ub2ec\ud55c\ub2e4.\n      <\/strong>\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>4. \uc6a9\uc5b4 \uac04 \uad00\uacc4<\/h2>\n\n\n  <h3>4.1 \uc555\ub825\uc744 \ubb34\uc5c7\uc73c\ub85c \ubc14\uafb8\ub294\uac00?<\/h3>\n\n  <div class=\"table-wrap\">\n\n    <table>\n\n      <thead>\n        <tr>\n          <th>\uc7a5\uce58<\/th>\n          <th>\ubcc0\ud658 \uad00\uacc4<\/th>\n        <\/tr>\n      <\/thead>\n\n      <tbody>\n\n        <tr>\n          <td>Manometer<\/td>\n          <td>Pressure \u2192 Liquid Height<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Mechanical Element<\/td>\n          <td>Pressure \u2192 Force \/ Displacement<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Strain Gauge<\/td>\n          <td>Pressure \u2192 Strain \u2192 Resistance<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Capacitance Sensor<\/td>\n          <td>Pressure \u2192 Diaphragm Position \u2192 Capacitance<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Resonant Sensor<\/td>\n          <td>Pressure \u2192 Force \u2192 Frequency<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Force Balance<\/td>\n          <td>Pressure \u2192 Force \u2192 Counter Force<\/td>\n        <\/tr>\n\n        <tr>\n          <td>DP Transmitter<\/td>\n          <td>PH, PL \u2192 \u0394P<\/td>\n        <\/tr>\n\n      <\/tbody>\n\n    <\/table>\n\n  <\/div>\n\n\n  <h3>4.2 \uc9c1\uc811 \uce21\uc815\uc5d0\uc11c \uac04\uc811 \uce21\uc815\uc73c\ub85c<\/h3>\n\n  <div class=\"flow\">\n    Pressure\n    \u2192 Differential Pressure\n    \u2192 Inferential Measurement\n  <\/div>\n\n  <p>\n    \ucc98\uc74c\uc5d0\ub294 pressure \uc790\uccb4\ub97c \uce21\uc815\ud55c\ub2e4.\n    \uadf8 \ub2e4\uc74c \ub450 pressure\uc758 \ucc28\uc774\ub97c \uce21\uc815\ud55c\ub2e4.\n    \ub9c8\uc9c0\ub9c9\uc73c\ub85c \ubb3c\ub9ac\uc2dd\uc744 \uc774\uc6a9\ud574 level\uacfc flow\ub97c \ucd94\uc815\ud55c\ub2e4.\n  <\/p>\n\n\n  <h3>4.3 Sensor\uc5d0\uc11c Measurement System\uc73c\ub85c<\/h3>\n\n  <div class=\"formula\">\n    Sensor\n    + Process Connection\n    + Accessories\n    + Operating Procedure\n    = Reliable Measurement\n  <\/div>\n\n  <div class=\"table-wrap\">\n\n    <table>\n\n      <thead>\n        <tr>\n          <th>\uc7a5\uce58<\/th>\n          <th>\uc5ed\ud560<\/th>\n        <\/tr>\n      <\/thead>\n\n      <tbody>\n\n        <tr>\n          <td>Manifold<\/td>\n          <td>Process \uc5f0\uacb0, Isolation, Equalization<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Bleed \/ Vent<\/td>\n          <td>Residual Pressure \ubc0f Trapped Fluid \uc81c\uac70<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Stinger<\/td>\n          <td>Field Test Pressure \uc5f0\uacb0<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Damper \/ Snubber<\/td>\n          <td>Pressure Pulsation \uc644\ud654<\/td>\n        <\/tr>\n\n        <tr>\n          <td>Isolating Diaphragm<\/td>\n          <td>Process Fluid\uc640 Sensor \uaca9\ub9ac<\/td>\n        <\/tr>\n\n      <\/tbody>\n\n    <\/table>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>5. \uae30\uc5b5\uc744 \uc704\ud55c \uc2a4\ud1a0\ub9ac<\/h2>\n\n\n  <div class=\"story\">\n\n    <h3>Step 1. \uc555\ub825\uc744 \uac00\uc7a5 \ub2e8\uc21c\ud558\uac8c \uce21\uc815\ud55c\ub2e4<\/h3>\n\n    <p>\n      Tank\uc5d0 pressure\uac00 \uc874\uc7ac\ud55c\ub2e4.\n      \uac00\uc7a5 \ub2e8\uc21c\ud55c \ubc29\ubc95\uc740 \uc561\uc8fc\ub97c \uc5f0\uacb0\ud558\ub294 \uac83\uc774\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      P = \u03c1gh\n    <\/div>\n\n    <p>\n      \uc5ec\uae30\uc11c gauge pressure, differential pressure,\n      absolute pressure\uc758 \uae30\uc900 \ucc28\uc774\ub97c \ubc30\uc6b4\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <div class=\"story\">\n\n    <h3>Step 2. \uc561\uc8fc \ub300\uc2e0 \uae30\uacc4 \uad6c\uc870\ubb3c\uc744 \uc0ac\uc6a9\ud55c\ub2e4<\/h3>\n\n    <p>\n      \uc0b0\uc5c5\ud604\uc7a5\uc5d0\uc11c \uc561\uc8fc\ub97c \ud56d\uc0c1 \uc0ac\uc6a9\ud560 \uc218\ub294 \uc5c6\ub2e4.\n    <\/p>\n\n    <p>\n      \ub530\ub77c\uc11c Bourdon tube, diaphragm, bellows\ub97c \uc774\uc6a9\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Pressure\n      \u2192 Force\n      \u2192 Mechanical Deformation\n    <\/div>\n\n  <\/div>\n\n\n  <div class=\"story\">\n\n    <h3>Step 3. \uae30\uacc4\uc801 \ubcc0\ud654\ub97c \uc804\uae30\uc2e0\ud638\ub85c \ubc14\uafbc\ub2e4<\/h3>\n\n    <p>\n      Control room\uae4c\uc9c0 \uce21\uc815\uac12\uc744 \uc804\ub2ec\ud558\uae30 \uc704\ud574\n      electrical sensor\uac00 \ud544\uc694\ud558\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Strain \u2192 R\n      <br><br>\n      Diaphragm Position \u2192 C\n      <br><br>\n      Tension \u2192 f\n    <\/div>\n\n  <\/div>\n\n\n  <div class=\"story\">\n\n    <h3>Step 4. Sensor\uac00 \ub9ce\uc774 \uc6c0\uc9c1\uc774\uc9c0 \uc54a\uac8c \ud55c\ub2e4<\/h3>\n\n    <p>\n      Mechanical displacement\uac00 \ub9ce\uc73c\uba74\n      spring characteristic\uc774\ub098 fatigue\uac00 \uce21\uc815\uc5d0 \uc601\ud5a5\uc744 \uc904 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <p>\n      \ub530\ub77c\uc11c pressure\uac00 \ub9cc\ub4e0 \ud798\uc744\n      \ubc18\ub300 \ud798\uc73c\ub85c \uc989\uc2dc \uc0c1\uc1c4\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      Fsensed = Fbalance\n    <\/div>\n\n    <p>\n      Force bar\uc758 position error\uac00 0\uc774 \ub418\uba74\n      balance\uac00 \uc774\ub8e8\uc5b4\uc9c4 \uac83\uc774\ub2e4.\n    <\/p>\n\n    <p>\n      \uc774\ub54c \ud544\uc694\ud55c pneumatic pressure \ub610\ub294 electric current\uac00\n      pressure\ub97c \ub098\ud0c0\ub0b8\ub2e4.\n    <\/p>\n\n  <\/div>\n\n\n  <div class=\"story\">\n\n    <h3>Step 5. \ub450 \uc9c0\uc810\uc758 \uc555\ub825\ucc28\ub97c \uce21\uc815\ud55c\ub2e4<\/h3>\n\n    <div class=\"formula\">\n      \u0394P = PH \u2212 PL\n    <\/div>\n\n    <p>\n      DP transmitter\ub85c \ucc28\uc555\uc744 \uce21\uc815\ud558\uba74\n      level\uacfc flow\uae4c\uc9c0 \uac04\uc811 \uce21\uc815\ud560 \uc218 \uc788\ub2e4.\n    <\/p>\n\n    <div class=\"formula\">\n      h = P \/ (\u03c1g)\n    <\/div>\n\n    <div class=\"formula\">\n      Q \u221d \u221a\u0394P\n    <\/div>\n\n  <\/div>\n\n\n  <div class=\"story\">\n\n    <h3>Step 6. \uc2e4\uc81c \ud604\uc7a5\uc5d0 \uc124\uce58\ud55c\ub2e4<\/h3>\n\n    <p>\n      \uc2e4\uc81c process\uc5d0\ub294 pulsation, vibration,\n      trapped gas, condensed liquid,\n      residual pressure, corrosion \ub4f1\uc774 \uc874\uc7ac\ud55c\ub2e4.\n    <\/p>\n\n    <div class=\"flow\">\n      Process\n      \u2192 Manifold \/ Bleed \/ Damper \/ Isolation\n      \u2192 Pressure Transmitter\n      \u2192 Signal\n      \u2192 Control System\n    <\/div>\n\n  <\/div>\n\n\n  <div class=\"story\">\n\n    <h3>Step 7. \uc720\uc9c0\ubcf4\uc218\ub97c \uc704\ud574 \uc548\uc804\ud558\uac8c \ubd84\ub9ac\ud55c\ub2e4<\/h3>\n\n    <p>\n      DP transmitter\ub97c \ubd84\ub9ac\ud560 \ub54c\ub294\n      valve\uc758 \ucd5c\uc885 \uc0c1\ud0dc\ubfd0 \uc544\ub2c8\ub77c \uc870\uc791 \uc21c\uc11c\uae4c\uc9c0 \uc911\uc694\ud558\ub2e4.\n    <\/p>\n\n    <div class=\"sequence\">\n      Normal\n      \u2192 H Close\n      \u2192 Equalize Open\n      \u2192 L Close\n      \u2192 H\/L Bleed Open\n      \u2192 Removed\n    <\/div>\n\n    <div class=\"sequence\">\n      Removed\n      \u2192 H\/L Bleed Close\n      \u2192 L Open\n      \u2192 Equalize Close\n      \u2192 H Open\n      \u2192 Normal\n    <\/div>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>6. Chapter 19 \ud575\uc2ec \uae30\uc5b5 \ubb38\uc7a5<\/h2>\n\n  <div class=\"memory\">\n\n    <ol>\n\n      <li>\n        <strong>\n          Pressure\ub294 \ud798\uacfc \ubcc0\ud615\uc744 \ub9cc\ub4e4\uace0,\n          sensor\ub294 \uc774\ub97c R, C, f \ub610\ub294 balancing force\ub85c \ubcc0\ud658\ud55c\ub2e4.\n        <\/strong>\n      <\/li>\n\n      <li>\n        <strong>\n          DP transmitter\ub294 PH \u2212 PL\uc744 \uce21\uc815\ud558\uace0,\n          \ucc28\uc555\uc744 \uc774\uc6a9\ud558\uc5ec level\uacfc flow\ub97c \uac04\uc811 \uce21\uc815\ud560 \uc218 \uc788\ub2e4.\n        <\/strong>\n      <\/li>\n\n      <li>\n        <strong>\n          Force-balance\ub294 force \uc790\uccb4\ub97c \uc9c1\uc811 \ube44\uad50\ud558\ub294 \uac83\uc774 \uc544\ub2c8\ub77c,\n          position error\ub97c 0\uc73c\ub85c \ub9cc\ub4dc\ub294 \ub370 \ud544\uc694\ud55c counter-force\ub97c \uce21\uc815\ud55c\ub2e4.\n        <\/strong>\n      <\/li>\n\n      <li>\n        <strong>\n          \uc815\ud655\ud55c pressure measurement\ub294 transmitter\ubfd0 \uc544\ub2c8\ub77c\n          manifold, bleed, damping, isolation,\n          \uc62c\ubc14\ub978 valve operating sequence\ub97c \ud3ec\ud568\ud55c \uc804\uccb4 \uc2dc\uc2a4\ud15c\uc758 \ubb38\uc81c\uc774\ub2e4.\n        <\/strong>\n      <\/li>\n\n    <\/ol>\n\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <h2>7. \ucd5c\uc885 \uc554\uae30 \uad6c\uc870<\/h2>\n\n  <div class=\"flow\">\n    Pressure\n    <br>\u2193<br>\n    Liquid Height \/ Force \/ Deformation\n    <br>\u2193<br>\n    R \/ C \/ f \/ Force Balance\n    <br>\u2193<br>\n    Pressure Transmitter\n    <br>\u2193<br>\n    Differential Pressure\n    <br>\u2193<br>\n    Level \/ Flow Inference\n    <br>\u2193<br>\n    Manifold \/ Bleed \/ Damping \/ Isolation\n    <br>\u2193<br>\n    Reliable Field Measurement\n  <\/div>\n\n  <div class=\"memory\">\n    <strong>\ud55c \ubb38\uc7a5 \uc815\ub9ac<\/strong><br><br>\n\n    \uc555\ub825\uc744 \uc561\uc8fc, \uae30\uacc4\uc801 \ubcc0\ud615, \uc800\ud56d, \uc815\uc804\uc6a9\ub7c9,\n    \uacf5\uc9c4\uc8fc\ud30c\uc218 \ub610\ub294 force balance\ub85c \uce21\uc815\ud558\uace0,\n    \ucc28\uc555\uc744 \uc774\uc6a9\ud558\uc5ec \ub2e4\ub978 \uacf5\uc815\ubcc0\uc218\uae4c\uc9c0 \ucd94\uc815\ud558\uba70,\n    \ud604\uc7a5\uc5d0\uc11c\ub294 manifold\uc640 \uac01\uc885 accessory\ub97c \uc774\uc6a9\ud558\uc5ec\n    \uc548\uc804\ud558\uace0 \uc2e0\ub8b0\uc131 \uc788\ub294 pressure measurement system\uc744 \uad6c\uc131\ud55c\ub2e4.\n  <\/div>\n\n\n  <!-- ================================================= -->\n  <div class=\"keywords\">\n    Pressure Measurement, Differential Pressure, Force Balance, Valve Manifold, Pressure Accessories\n  <\/div>\n\n<\/div>\n\n\n\n<div data-wp-interactive=\"core\/file\" class=\"wp-block-file\"><object data-wp-bind--hidden=\"!state.hasPdfPreview\" hidden class=\"wp-block-file__embed\" data=\"https:\/\/now0930.pe.kr\/wordpress\/wp-content\/uploads\/2026\/09\/Lessons_In_Industrial_Instrumentation-3.pdf\" type=\"application\/pdf\" style=\"width:100%;height:600px\" aria-label=\"Lessons_In_Industrial_Instrumentation\uc758 \uc0bd\uc785.\"><\/object><a id=\"wp-block-file--media-59679cfe-44b4-4703-a1f2-0b25e255bb90\" href=\"https:\/\/now0930.pe.kr\/wordpress\/wp-content\/uploads\/2026\/09\/Lessons_In_Industrial_Instrumentation-3.pdf\">Lessons_In_Industrial_Instrumentation<\/a><a href=\"https:\/\/now0930.pe.kr\/wordpress\/wp-content\/uploads\/2026\/09\/Lessons_In_Industrial_Instrumentation-3.pdf\" class=\"wp-block-file__button wp-element-button\" download aria-describedby=\"wp-block-file--media-59679cfe-44b4-4703-a1f2-0b25e255bb90\">\ub2e4\uc6b4\ub85c\ub4dc<\/a><\/div>\n\n\n\n<pre class=\"wp-block-code\"><code>\\documentclass&#91;11pt,a4paper]{article}\n\n\\usepackage{kotex}\n\\usepackage&#91;margin=22mm]{geometry}\n\\usepackage{amsmath,amssymb}\n\\usepackage{booktabs}\n\\usepackage{tabularx}\n\\usepackage{array}\n\\usepackage{enumitem}\n\\usepackage{xcolor}\n\\usepackage{hyperref}\n\n\\setlength{\\parindent}{0pt}\n\\setlength{\\parskip}{0.55em}\n\\renewcommand{\\arraystretch}{1.35}\n\n\\newcommand{\\key}&#91;1]{\\textbf{#1}}\n\\newcommand{\\flow}&#91;1]{%\n\\begin{center}\n\\fbox{\n\\parbox{0.91\\linewidth}{\n\\centering\n#1\n}}\n\\end{center}\n}\n\n\\title{Chapter 19. Continuous Pressure Measurement}\n\\author{}\n\\date{}\n\n\\begin{document}\n\n\\maketitle\n\\tableofcontents\n\\newpage\n\n% ============================================================\n\\section{Chapter 19 \uc804\uccb4 \ud750\ub984}\n\nChapter 19\uc758 \uc911\uc2ec \uc9c8\ubb38\uc740 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{quote}\n\\textbf{\uacf5\uc815\uc758 \uc555\ub825\uc744 \uc5b4\ub5bb\uac8c \uac10\uc9c0\ud558\uace0, \uce21\uc815 \uac00\ub2a5\ud55c \ubb3c\ub9ac\ub7c9\uc73c\ub85c \ubcc0\ud658\ud558\uba70,\n\uc804\uae30 \ub610\ub294 \uacf5\uc555 \uc2e0\ud638\ub85c \uc804\ub2ec\ud558\uace0, \uc2e4\uc81c \ud604\uc7a5\uc5d0\uc11c \uc815\ud655\ud558\uac8c \uce21\uc815\ud560 \uac83\uc778\uac00?}\n\\end{quote}\n\n\uc804\uccb4 \ud750\ub984\uc740 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\flow{\nPressure\n$\\rightarrow$\nLiquid Height \/ Mechanical Force\n$\\rightarrow$\nElectrical Quantity\n$\\rightarrow$\nPressure Transmitter\n$\\rightarrow$\nDifferential Pressure\n$\\rightarrow$\nInferential Measurement\n$\\rightarrow$\nField Accessories\n}\n\n\uc989, \uc555\ub825\uc758 \uae30\ubcf8 \uce21\uc815\uc5d0\uc11c \uc2dc\uc791\ud558\uc5ec\n\uc13c\uc11c \uc6d0\ub9ac, transmitter, \ucc28\uc555 \uce21\uc815,\n\uac04\uc811\uce21\uc815, \uc2e4\uc81c \uc124\uce58\uc640 \uc720\uc9c0\ubcf4\uc218 \ubb38\uc81c\ub85c \ud655\uc7a5\ub41c\ub2e4.\n\n% ============================================================\n\\section{\uc6a9\uc5b4 \uc815\ub9ac}\n\n% ------------------------------------------------------------\n\\subsection{Pressure}\n\n\uc555\ub825\uc740 \ub2e8\uc704 \uba74\uc801\uc5d0 \uc791\uc6a9\ud558\ub294 \ud798\uc774\ub2e4.\n\n\\&#91;\nP=\\frac{F}{A}\n\\]\n\n\ub530\ub77c\uc11c \uc77c\uc815\ud55c \uba74\uc801\uc744 \uac00\uc9c4 sensing element\uc5d0 \uc555\ub825\uc774 \uc791\uc6a9\ud558\uba74\n\ud798\uc73c\ub85c \ubcc0\ud658\ud560 \uc218 \uc788\ub2e4.\n\n\\&#91;\nF=PA\n\\]\n\n\uc555\ub825\uc740 \uadf8 \uc790\uccb4\ub85c \uc911\uc694\ud55c process variable\uc774\uc9c0\ub9cc,\n\ub2e4\ub978 \uacf5\uc815\ubcc0\uc218\ub97c \uac04\uc811\uc801\uc73c\ub85c \uce21\uc815\ud558\ub294 \ub370\ub3c4 \uc0ac\uc6a9\ud55c\ub2e4.\n\n\ub300\ud45c\uc801\uc778 \uad00\uacc4\ub294 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\&#91;\nP=\\rho gh\n\\]\n\n\\&#91;\nQ\\propto\\sqrt{\\Delta P}\n\\]\n\n\ub530\ub77c\uc11c \uc555\ub825\uc744 \uc774\uc6a9\ud558\uc5ec liquid level \ub610\ub294 fluid flow\ub97c \ucd94\uc815\ud560 \uc218 \uc788\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Manometer}\n\nManometer\ub294 \uc555\ub825\uc744 \uc561\uc8fc\uc758 \ub192\uc774\ub85c \ubcc0\ud658\ud558\uc5ec \uce21\uc815\ud55c\ub2e4.\n\n\\&#91;\nP=\\rho gh\n\\]\n\n\\flow{\nPressure\n$\\rightarrow$\nLiquid Column Height\n}\n\n% ------------------------------------------------------------\n\\subsubsection{Gauge Pressure}\n\n\ud55c\ucabd pressure port\ub97c \ub300\uae30\uc5d0 \uac1c\ubc29\ud55c\ub2e4.\n\n\ub530\ub77c\uc11c process pressure\uc640 atmospheric pressure\uc758 \ucc28\uc774\ub97c \uce21\uc815\ud55c\ub2e4.\n\n\\&#91;\nP_g\n=\nP_{\\text{process}}\n-\nP_{\\text{atm}}\n\\]\n\n\uc989,\n\n\\&#91;\n\\boxed{\\text{Gauge Pressure = Atmospheric Pressure \uae30\uc900}}\n\\]\n\n\uc774\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Differential Pressure}\n\n\ub450 pressure port\ub97c \ubaa8\ub450 \uc0ac\uc6a9\ud55c\ub2e4.\n\n\\&#91;\n\\Delta P=P_H-P_L\n\\]\n\n\ub530\ub77c\uc11c \ub450 \uc9c0\uc810\uc758 \uc555\ub825\ucc28\ub97c \uc9c1\uc811 \uce21\uc815\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Absolute Pressure}\n\n\ud55c\ucabd pressure port\ub97c \ubc00\ud3d0\ub41c vacuum chamber\uc5d0 \uc5f0\uacb0\ud55c\ub2e4.\n\n\ub530\ub77c\uc11c process pressure\ub97c vacuum\uacfc \ube44\uad50\ud55c\ub2e4.\n\n\\&#91;\nP_{\\text{abs}}\n=\nP_{\\text{process}}\n-\nP_{\\text{vacuum}}\n\\]\n\n\uc774 \uc6d0\ub9ac\ub97c \uc774\uc6a9\ud55c \ub300\ud45c\uc801\uc778 \uc7a5\uce58\uac00 mercury barometer\uc774\ub2e4.\n\n\\&#91;\n\\boxed{\\text{Absolute Pressure = Vacuum \uae30\uc900}}\n\\]\n\n% ------------------------------------------------------------\n\\subsubsection{Well-type Manometer}\n\nWell\uc758 \ub2e8\uba74\uc801\uc744 \ud22c\uba85\ud55c manometer tube\ubcf4\ub2e4 \ub9e4\uc6b0 \ud06c\uac8c \ub9cc\ub4e0\ub2e4.\n\n\ub530\ub77c\uc11c well \ub0b4\ubd80 \uc561\uba74\uc758 \ub192\uc774 \ubcc0\ud654\ub294 \ub9e4\uc6b0 \uc791\ub2e4.\n\n\uadf8 \uacb0\uacfc \ub450 \uc561\uc8fc\uc758 \ub192\uc774\ucc28\ub97c \ubaa8\ub450 \uc77d\uc9c0 \uc54a\uace0\n\ud55c\ucabd \uc561\uc8fc\uc758 \ub192\uc774\ub9cc \uc77d\uc744 \uc218 \uc788\ub2e4.\n\n\\&#91;\n\\boxed{\\text{Single-point Reading}}\n\\]\n\nWell\uc758 \uc561\uba74 \ubcc0\ud654\uac00 \ubb34\uc2dc\ud560 \uc218 \uc5c6\uc744 \uacbd\uc6b0\uc5d0\ub294\nscale division\uc744 \ubcf4\uc815\ud558\uc5ec \uc624\ucc28\ub97c \ubcf4\uc0c1\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Inclined Manometer}\n\nManometer tube\ub97c \uae30\uc6b8\uc774\uba74\n\ub3d9\uc77c\ud55c \uc218\uc9c1 \ub192\uc774 \ubcc0\ud654\uc5d0 \ub300\ud574 \uc561\uccb4\uac00 tube\ub97c \ub530\ub77c\n\ub354 \uae34 \uac70\ub9ac\ub97c \uc774\ub3d9\ud55c\ub2e4.\n\n\ub530\ub77c\uc11c \uc791\uc740 \uc555\ub825 \ubcc0\ud654\uac00\n\ub354 \ud070 \uae38\uc774 \ubcc0\ud654\ub85c \ub098\ud0c0\ub09c\ub2e4.\n\n\\&#91;\n\\boxed{\n\\text{Inclination}\n\\rightarrow\n\\text{Travel Distance \uc99d\uac00}\n\\rightarrow\n\\text{Sensitivity \uc99d\uac00}\n}\n\\]\n\n% ============================================================\n\\subsection{Mechanical Pressure Elements}\n\n\uc555\ub825\uc744 \uae30\uacc4\uc801 \ud798 \ub610\ub294 \ubcc0\ud615\uc73c\ub85c \ubc14\uafb8\uc5b4 \uce21\uc815\ud55c\ub2e4.\n\n\ub300\ud45c\uc801\uc778 element\ub294 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{itemize}&#91;leftmargin=2em]\n    \\item Bourdon tube\n    \\item Diaphragm\n    \\item Bellows\n\\end{itemize}\n\n\uae30\ubcf8 \uad00\uacc4\ub294\n\n\\&#91;\nF=PA\n\\]\n\n\uc774\ub2e4.\n\n\ub530\ub77c\uc11c\n\n\\flow{\nPressure\n$\\rightarrow$\nForce\n$\\rightarrow$\nMechanical Deformation\n}\n\n\uc73c\ub85c \uc774\ud574\ud560 \uc218 \uc788\ub2e4.\n\nMechanical pressure element\ub294\n\uc624\ub7ab\ub3d9\uc548 \uc0b0\uc5c5\ud604\uc7a5\uc5d0\uc11c \uc0ac\uc6a9\ub41c\n\uacac\uace0\ud558\uace0 \uac80\uc99d\ub41c \uce21\uc815 \ubc29\uc2dd\uc774\ub2e4.\n\n% ============================================================\n\\subsection{Electrical Pressure Elements}\n\n\uc555\ub825\uc5d0 \uc758\ud574 \ubc1c\uc0dd\ud55c \uae30\uacc4\uc801 \ubcc0\ud654\ub97c\n\uc804\uae30\uc801\uc73c\ub85c \uce21\uc815 \uac00\ub2a5\ud55c \uac12\uc73c\ub85c \ubcc0\ud658\ud55c\ub2e4.\n\nChapter 19\uc5d0\uc11c\ub294 \ub300\ud45c\uc801\uc73c\ub85c \ub2e4\uc74c \ubc29\uc2dd\uc744 \ub2e4\ub8ec\ub2e4.\n\n\\begin{center}\n\\begin{tabularx}{0.95\\linewidth}{\n>{\\bfseries}l\nX\nX}\n\\toprule\nSensor &amp; \uc555\ub825\uc774 \ubcc0\ud654\uc2dc\ud0a4\ub294 \uac83 &amp; \ucd5c\uc885 \uce21\uc815\ub7c9 \\\\\n\\midrule\n\nPiezoresistive \/ Strain Gauge\n&amp; Mechanical strain\n&amp; Resistance $R$ \\\\\n\nDifferential Capacitance\n&amp; Diaphragm position\n&amp; Capacitance $C$ \\\\\n\nResonant Element\n&amp; Tension \/ Mechanical state\n&amp; Resonant frequency $f$ \\\\\n\n\\bottomrule\n\\end{tabularx}\n\\end{center}\n\n\ub530\ub77c\uc11c \ub2e4\uc74c\uacfc \uac19\uc774 \uae30\uc5b5\ud55c\ub2e4.\n\n\\&#91;\n\\boxed{\nPressure\n\\rightarrow\nR,\\;C,\\;f\n}\n\\]\n\n% ------------------------------------------------------------\n\\subsubsection{Piezoresistive \/ Strain-gauge Sensor}\n\n\uc555\ub825\uc774 diaphragm \ub4f1\uc5d0 \uc791\uc6a9\ud558\uba74\n\uae30\uacc4\uc801 strain\uc774 \ubc1c\uc0dd\ud55c\ub2e4.\n\n\uc774 strain\uc5d0 \uc758\ud574 sensor\uc758 electrical resistance\uac00 \ubcc0\ud654\ud55c\ub2e4.\n\n\\flow{\nPressure\n$\\rightarrow$\nMechanical Strain\n$\\rightarrow$\nResistance Change\n$\\rightarrow$\nElectrical Signal\n}\n\n\uae08\uc18d \ub610\ub294 semiconductor \uc7ac\ub8cc\ub97c \uc0ac\uc6a9\ud560 \uc218 \uc788\ub2e4.\n\nSemiconductor\ub294 \uc791\uc740 \ubcc0\ud615\uc5d0\ub3c4\n\uc0c1\ub300\uc801\uc73c\ub85c \ud070 \uc800\ud56d \ubcc0\ud654\ub97c \uc5bb\uc744 \uc218 \uc788\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Differential Capacitance Sensor}\n\n\ub450 \uc555\ub825\uc758 \ucc28\uc774\uac00 sensing diaphragm\uc5d0 \ud798\uc744 \uac00\ud55c\ub2e4.\n\n\\&#91;\nF=(P_H-P_L)A\n\\]\n\nDiaphragm\uc774 \ud55c\ucabd\uc73c\ub85c \uc774\ub3d9\ud558\uba74\n\uc591\ucabd capacitance\uac00 \uc11c\ub85c \ubc18\ub300 \ubc29\ud5a5\uc73c\ub85c \ubcc0\ud55c\ub2e4.\n\nCapacitance\uc758 \uae30\ubcf8 \uad00\uacc4\ub294\n\n\\&#91;\nC=\\frac{\\epsilon A}{d}\n\\]\n\n\uc774\ub2e4.\n\n\ub530\ub77c\uc11c\n\n\\&#91;\nd_1\\downarrow\n\\Rightarrow\nC_1\\uparrow\n\\]\n\n\\&#91;\nd_2\\uparrow\n\\Rightarrow\nC_2\\downarrow\n\\]\n\n\uc774\ub2e4.\n\n\uc13c\uc11c \ud68c\ub85c\ub294 high-frequency AC excitation\uc744 \uc774\uc6a9\ud558\uc5ec\n\ub450 capacitance\uc758 \ucc28\uc774\ub97c \uac80\ucd9c\ud55c\ub2e4.\n\n\uadf8 \ucc28\uc774\ub97c DC signal\ub85c \ubcc0\ud658\ud558\uc5ec\n\ucd5c\uc885 pressure signal\uc744 \ub9cc\ub4e0\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Isolating Diaphragm\uacfc Fill Fluid}\n\nProcess fluid\uc758 \uc555\ub825\uc774\nsensing diaphragm\uc5d0 \uc9c1\uc811 \uc804\ub2ec\ub418\uc9c0 \uc54a\uace0\n\ub2e4\uc74c \uacbd\ub85c\ub97c \ud1b5\ud574 \uc804\ub2ec\ub420 \uc218 \uc788\ub2e4.\n\n\\flow{\nProcess Pressure\n$\\rightarrow$\nIsolating Diaphragm\n$\\rightarrow$\nFill Fluid\n$\\rightarrow$\nSensing Diaphragm\n}\n\n\uc774 \uad6c\uc870\uc758 \uc911\uc694\ud55c \ubaa9\uc801\uc740\n\\key{\uce21\uc815 \uae30\ub2a5\uacfc \uacfc\uc555 \ubcf4\ud638 \uae30\ub2a5\uc744 \ubd84\ub9ac\ud558\ub294 \uac83}\uc774\ub2e4.\n\n\\begin{itemize}\n    \\item Sensing diaphragm:\n    capacitance \uce21\uc815\n    \\item Isolating diaphragm:\n    process pressure \uc804\ub2ec\n    \\item Fill fluid:\n    diaphragm \uc0ac\uc774 \uc555\ub825 \uc804\ub2ec\n    \\item Solid frame:\n    isolating diaphragm\uc758 \uacfc\ub3c4\ud55c \uc774\ub3d9 \uc81c\ud55c\n\\end{itemize}\n\nCapacitance sensing diaphragm\uc740\n\uc815\uc0c1 \uce21\uc815\uc744 \uc704\ud574 conductive frame\uacfc \uc811\ucd09\ud558\uc9c0 \uc54a\uc544\uc57c \ud55c\ub2e4.\n\n\uadf8\ub7ec\ub098 overpressure protection\uc744 \uc704\ud574\uc11c\ub294\ndiaphragm\uc758 \uc774\ub3d9\uc744 \uc81c\ud55c\ud560 solid backstop\uc774 \ud544\uc694\ud558\ub2e4.\n\n\ub530\ub77c\uc11c \ud558\ub098\uc758 diaphragm\uc5d0 \ub450 \uae30\ub2a5\uc744 \ubaa8\ub450 \ubd80\uc5ec\ud558\uc9c0 \uc54a\uace0\n\uae30\ub2a5\uc744 \ubd84\ub9ac\ud55c\ub2e4.\n\n\uacfc\uc555\uc774 \ubc1c\uc0dd\ud558\uba74 isolating diaphragm\uc774\nsolid frame\uc5d0 \ubc00\ucc29\ub418\uc5b4 \ub354 \uc774\uc0c1 \uc6c0\uc9c1\uc774\uc9c0 \uc54a\ub294\ub2e4.\n\n\uadf8 \uacb0\uacfc \ucd94\uac00 process pressure\uac00 \uac00\ud574\uc838\ub3c4\nsensing diaphragm\uc5d0 \uacfc\ub3c4\ud55c \ud798\uc744 \uc804\ub2ec\ud558\uc9c0 \uc54a\ub294\ub2e4.\n\n\\&#91;\n\\boxed{\n\\text{Measurement}\n\\neq\n\\text{Overpressure Protection}\n}\n\\]\n\n\ub450 \uae30\ub2a5\uc744 \uc11c\ub85c \ub2e4\ub978 diaphragm\uc774 \ub2f4\ub2f9\ud55c\ub2e4.\n\n% ============================================================\n\\subsection{Resonant Element Sensor}\n\n\uc904\uc774\ub098 resonant element\uc758 \uc7a5\ub825\uc774 \uc99d\uac00\ud558\uba74\nnatural frequency\uac00 \uc99d\uac00\ud55c\ub2e4.\n\n\uc904\uc758 \uae30\ubcf8 \uacf5\uc9c4\uc8fc\ud30c\uc218\ub294\n\n\\&#91;\nf=\n\\frac{1}{2L}\n\\sqrt{\\frac{F_T}{\\mu}}\n\\]\n\n\uc774\ub2e4.\n\n\uc5ec\uae30\uc11c\n\n\\begin{itemize}\n    \\item $f$: fundamental resonant frequency\n    \\item $L$: string length\n    \\item $F_T$: string tension\n    \\item $\\mu$: unit mass\n\\end{itemize}\n\n\uc774\ub2e4.\n\n\uc555\ub825\uc774 diaphragm \ub610\ub294 bellows\uc5d0 \uc791\uc6a9\ud558\uba74\n\ud798\uc774 \ubc1c\uc0dd\ud558\uace0,\n\uc774 \ud798\uc774 resonant element\uc758 tension\uc744 \ubcc0\ud654\uc2dc\ud0a8\ub2e4.\n\n\\flow{\nPressure\n$\\rightarrow$\nForce\n$\\rightarrow$\nTension\n$\\rightarrow$\nResonant Frequency\n}\n\nOscillator circuit\uc740 resonant element\ub97c \uacc4\uc18d \uc9c4\ub3d9\uc2dc\ud0a4\uace0,\ndetector\ub294 \uadf8 resonant frequency\ub97c \uce21\uc815\ud55c\ub2e4.\n\n\uc911\uc694\ud55c \uc810\uc740\n\n\\&#91;\nf\\propto\\sqrt{F_T}\n\\]\n\n\uc774\ubbc0\ub85c force\uc640 frequency \uad00\uacc4\uac00 \uc120\ud615\uc774 \uc544\ub2c8\ub77c\ub294 \uac83\uc774\ub2e4.\n\n\ub530\ub77c\uc11c transmitter \ub0b4\ubd80\uc5d0\uc11c\nelectronic characterizing function\uc744 \uc774\uc6a9\ud558\uc5ec\n\uce21\uc815\uac12\uc744 linearize\ud574\uc57c \ud55c\ub2e4.\n\n\\&#91;\n\\boxed{\nFrequency Measurement\n\\rightarrow\nLinearization\n\\rightarrow\nPressure\n}\n\\]\n\n% ============================================================\n\\subsection{Force-Balance Pressure Transmitter}\n\nForce-balance \ubc29\uc2dd\uc740\nprocess pressure\uac00 \ub9cc\ub4e0 \ud798\uc744\n\ub2e4\ub978 \uc870\uc808 \uac00\ub2a5\ud55c \ud798\uc73c\ub85c \uc0c1\uc1c4\ud55c\ub2e4.\n\n\uae30\ubcf8 \uc6d0\ub9ac\ub294 self-balancing system\uc774\ub2e4.\n\n\\&#91;\nF_{\\text{sensed}}\n=\nF_{\\text{balance}}\n\\]\n\n\uc555\ub825\uc774 sensing diaphragm\uc5d0 \uc791\uc6a9\ud558\uba74\n\n\\&#91;\nF_{\\text{sensed}}\n=\n\\Delta P A\n\\]\n\n\uc758 \ud798\uc774 \ubc1c\uc0dd\ud55c\ub2e4.\n\n\uc774 \ud798 \ub54c\ubb38\uc5d0 force bar\uac00 \uae30\uc900 \uc704\uce58\uc5d0\uc11c \ubc97\uc5b4\ub098\uba74\n\ubc18\ub300 \ubc29\ud5a5\uc758 balancing force\ub97c \uc99d\uac00\uc2dc\ud0a8\ub2e4.\n\n\uade0\ud615\uc774 \ud68c\ubcf5\ub418\ub294 \uc21c\uac04\n\n\\&#91;\nF_{\\text{sensed}}\n=\nF_{\\text{balance}}\n\\]\n\n\uac00 \ub41c\ub2e4.\n\n\uade0\ud615\uc744 \ub9cc\ub4e4\uae30 \uc704\ud574 \ud544\uc694\ud55c balancing quantity\uac00\nprocess pressure\ub97c \ub098\ud0c0\ub0b8\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Force Balance\ub97c \uc5b4\ub5bb\uac8c \uac80\ucd9c\ud558\ub294\uac00?}\n\nForce\ub97c \uc9c1\uc811 \ube44\uad50\ud558\ub294 \uac83\uc774 \uc544\ub2c8\ub2e4.\n\n\ub450 \ud798\uc774 \ub2e4\ub974\uba74 force bar\uac00\n\uae30\uc900 \uc704\uce58\uc5d0\uc11c \uc57d\uac04 \uc6c0\uc9c1\uc778\ub2e4.\n\n\ub530\ub77c\uc11c \uc2dc\uc2a4\ud15c\uc740\n\n\\&#91;\n\\boxed{\\text{Force \uc790\uccb4\uac00 \uc544\ub2c8\ub77c Position Error\ub97c \uac80\ucd9c\ud55c\ub2e4}}\n\\]\n\n\uace0 \uc774\ud574\ud558\uba74 \ub41c\ub2e4.\n\nPosition error\uac00 0\uc73c\ub85c \ub3cc\uc544\uc624\uba74\n\ub450 force\uac00 balance\ub418\uc5c8\ub2e4\uace0 \ud310\ub2e8\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Pneumatic Force-Balance}\n\nPneumatic transmitter\uc5d0\uc11c\ub294\nbaffle--nozzle\uc774 force bar\uc758 \ubbf8\uc138\ud55c \uc704\uce58 \ubcc0\ud654\ub97c \uac80\ucd9c\ud55c\ub2e4.\n\n\\flow{\nForce Bar Displacement\n$\\rightarrow$\nBaffle--Nozzle\n$\\rightarrow$\nRelay\n$\\rightarrow$\nBellows Pressure\n$\\rightarrow$\nCounter Force\n}\n\nBaffle--nozzle\uc740 \uc808\ub300 \uc704\uce58\ub97c \uce21\uc815\ud558\ub294 \ubcc4\ub3c4\uc758 \uc704\uce58\uc13c\uc11c\ub77c\uae30\ubcf4\ub2e4\n\n\\&#91;\n\\boxed{\\text{Balance Position\uc5d0\uc11c \ubc97\uc5b4\ub0ac\ub294\uac00?}}\n\\]\n\n\ub97c \uac10\uc9c0\ud558\ub294 null detector \uc5ed\ud560\uc744 \ud55c\ub2e4.\n\n\uade0\ud615 \uc0c1\ud0dc\uc5d0\uc11c bellows\uc758 pneumatic pressure\uac00\nprocess pressure\uc758 \uc120\ud615\uc801\uc778 \ud45c\ud604\uc774 \ub41c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Electronic Force-Balance}\n\n\uc804\uc790\uc2dd\uc5d0\uc11c\ub294 balance sensor\uac00\nforce bar\uc758 \uc704\uce58 \ud3b8\ucc28\ub97c \uac80\ucd9c\ud55c\ub2e4.\n\n\\flow{\nForce Bar\n$\\rightarrow$\nBalance Sensor\n$\\rightarrow$\nAmplifier\n$\\rightarrow$\nForce Coil\n$\\rightarrow$\nCounter Force\n}\n\nForce coil\uc774 \ubc1c\uc0dd\uc2dc\ud0a4\ub294 \ud798\uc740\n\uc804\ub958\uc640 \uad00\ub828\ub41c\ub2e4.\n\n\\&#91;\nF_{\\text{balance}}\\propto I\n\\]\n\n\ub530\ub77c\uc11c equilibrium\uc5d0\uc11c force coil\uc5d0 \ud750\ub974\ub294 current\uac00\npressure\ub97c \ub098\ud0c0\ub0b8\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Force-Balance\uc758 \uc7a5\uc810}\n\n\\begin{itemize}\n    \\item \ub192\uc740 \uc120\ud615\uc131\n    \\item Sensing element\uc758 motion\uc774 \ub9e4\uc6b0 \uc791\uc74c\n    \\item Spring characteristic \ubcc0\ud654\uc758 \uc601\ud5a5\uc774 \uc791\uc74c\n    \\item Metal fatigue\uc5d0 \uc758\ud55c \uce21\uc815\uc624\ucc28\uc758 \uc601\ud5a5\uc744 \uc904\uc77c \uc218 \uc788\uc74c\n\\end{itemize}\n\nForce-balance \ubc29\uc2dd\uc5d0\uc11c\ub294\ndiaphragm\uc758 spring force\ub85c balance\uc2dc\ud0a4\ub294 \uac83\uc774 \uc544\ub2c8\ub77c\n\uc678\ubd80\uc758 pneumatic pressure \ub610\ub294 electric force\ub85c balance\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Force-Balance\uc758 \ub2e8\uc810}\n\n\\begin{itemize}\n    \\item \uad6c\uc870\uac00 \ud06c\uace0 \ubcf5\uc7a1\ud568\n    \\item External vibration\uc5d0 \ubbfc\uac10\ud568\n    \\item Vibration\uc774 inertial force\uac00 \ub418\uc5b4 output noise \ubc1c\uc0dd\n    \\item Electronic force-balance\ub294 balancing force \uc0dd\uc131\uc5d0 \ube44\uad50\uc801 \ud070 power \ud544\uc694\n    \\item Intrinsic safety \uad6c\ud604\uc5d0 \ubd88\ub9ac\ud560 \uc218 \uc788\uc74c\n\\end{itemize}\n\n% ============================================================\n\\subsection{Differential Pressure Transmitter}\n\nDP transmitter\ub294 \ub450 \uc555\ub825\uc758 \ucc28\uc774\ub97c \uce21\uc815\ud55c\ub2e4.\n\n\\&#91;\n\\Delta P\n=\nP_H-P_L\n\\]\n\n\\begin{itemize}\n    \\item H: High-pressure side\n    \\item L: Low-pressure side\n\\end{itemize}\n\n\ud575\uc2ec\uc740 \uc591\ucabd\uc5d0 \uacf5\ud1b5\uc73c\ub85c \uc874\uc7ac\ud558\ub294 pressure\ubcf4\ub2e4\n\ub450 pressure\uc758 \ucc28\uc774\uc5d0 \ubc18\uc751\ud558\ub294 \uac83\uc774\ub2e4.\n\n\uc804\uae30\ud68c\ub85c\uc758 differential amplifier\uc640 \uc720\uc0ac\ud558\uac8c \uc0dd\uac01\ud560 \uc218 \uc788\ub2e4.\n\n\\&#91;\nV_{\\text{out}}\n=\nA(V_1-V_2)\n\\]\n\n\uc989,\n\n\\&#91;\n\\boxed{\n\\text{Common Component\ubcf4\ub2e4 Difference\ub97c \uce21\uc815}\n}\n\\]\n\n\ud558\ub294 \uad6c\uc870\uc774\ub2e4.\n\n% ============================================================\n\\subsection{Inferential Measurement}\n\nPressure \ub610\ub294 differential pressure\ub97c \uc9c1\uc811 \uce21\uc815\ud55c \ub4a4\n\ubb3c\ub9ac\uc801 \uad00\uacc4\uc2dd\uc744 \uc774\uc6a9\ud558\uc5ec\n\ub2e4\ub978 process variable\uc744 \uacc4\uc0b0\ud560 \uc218 \uc788\ub2e4.\n\n\uc774\ub97c inferential measurement\ub77c\uace0 \ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Liquid Level}\n\n\uc815\uc218\uc555 \uad00\uacc4\ub294\n\n\\&#91;\nP=\\rho gh\n\\]\n\n\uc774\ub2e4.\n\n\ub530\ub77c\uc11c density\uac00 \uc54c\ub824\uc838 \uc788\uc73c\uba74\n\n\\&#91;\nh=\\frac{P}{\\rho g}\n\\]\n\n\ub85c liquid level\uc744 \uacc4\uc0b0\ud560 \uc218 \uc788\ub2e4.\n\n\\flow{\nPressure\n$\\rightarrow$\nLiquid Level\n}\n\n% ------------------------------------------------------------\n\\subsubsection{Fluid Flow}\n\nDifferential-pressure flow element\uc5d0\uc11c\ub294\n\n\\&#91;\nQ\\propto\\sqrt{\\Delta P}\n\\]\n\n\uad00\uacc4\ub97c \uc774\uc6a9\ud55c\ub2e4.\n\n\ub530\ub77c\uc11c\n\n\\flow{\nDifferential Pressure\n$\\rightarrow$\nFluid Flow\n}\n\n\ub85c \ubcc0\ud658\ud560 \uc218 \uc788\ub2e4.\n\n\uacb0\uad6d\n\n\\&#91;\n\\boxed{\nPressure\n\\rightarrow\nDifferential Pressure\n\\rightarrow\nInferential Measurement\n}\n\\]\n\n\ub85c \uce21\uc815 \ubc94\uc704\uac00 \ud655\uc7a5\ub41c\ub2e4.\n\n% ============================================================\n\\section{Pressure Sensor Accessories}\n\n\uc2e4\uc81c \uc0b0\uc5c5\ud604\uc7a5\uc5d0\uc11c\ub294\npressure transmitter \uc790\uccb4\ub9cc \uc815\ud655\ud558\ub2e4\uace0 \ud574\uc11c\n\uc804\uccb4 \uce21\uc815\uc774 \uc815\ud655\ud55c \uac83\uc740 \uc544\ub2c8\ub2e4.\n\n\ub2e4\uc74c\uacfc \uac19\uc740 \ud604\uc7a5 \ubb38\uc81c\uac00 \uc874\uc7ac\ud55c\ub2e4.\n\n\\begin{itemize}\n    \\item Pulsation\n    \\item Residual pressure\n    \\item Trapped gas\n    \\item Condensed liquid\n    \\item High temperature\n    \\item Corrosion\n    \\item Plugging\n    \\item Vibration\n    \\item Freezing\n\\end{itemize}\n\n\ub530\ub77c\uc11c pressure accessories\uc758 \ubaa9\uc801\uc740\n\n\\&#91;\n\\boxed{\n\\text{Pressure Sensor\uac00 \uc815\uc0c1\uc801\uc73c\ub85c \uce21\uc815\ud560 \uc218 \uc788\ub294 \ud658\uacbd\uc744 \ub9cc\ub4dc\ub294 \uac83}\n}\n\\]\n\n\uc774\ub2e4.\n\n% ============================================================\n\\subsection{Valve Manifold}\n\nDP transmitter\uc758 H\uc640 L pressure port\ub97c\nprocess impulse line\uc5d0 \uc5f0\uacb0\ud558\uace0,\ntransmitter\ub97c process\uc5d0\uc11c \uaca9\ub9ac\ud558\uba70,\nH\uc640 L pressure\ub97c equalize\ud558\uae30 \uc704\ud574 \uc0ac\uc6a9\ud55c\ub2e4.\n\nStandard 3-valve manifold\ub294 \ub2e4\uc74c \uc138 valve\ub85c \uad6c\uc131\ub41c\ub2e4.\n\n\\begin{itemize}\n    \\item High-side block valve\n    \\item Low-side block valve\n    \\item Equalizing valve\n\\end{itemize}\n\n\uc911\uc694\ud55c \uc810\uc740\n\\key{standard 3-valve manifold \uc790\uccb4\uc5d0\ub294 bleed valve\uac00 \ud3ec\ud568\ub418\uc9c0 \uc54a\ub294\ub2e4\ub294 \uac83}\uc774\ub2e4.\n\nH\uc640 L bleed fitting\uc740 transmitter flange\uc5d0\n\ubcc4\ub3c4\ub85c \uc124\uce58\ub420 \uc218 \uc788\ub2e4.\n\n\ub530\ub77c\uc11c \uc5ec\uae30\uc5d0\uc11c\ub294 \ub2e4\uc74c 5\uac1c\uc758 \uc870\uc791 \ub300\uc0c1\uc744 \uad6c\ubd84\ud55c\ub2e4.\n\n\\begin{enumerate}\n    \\item High-side block valve\n    \\item Low-side block valve\n    \\item Equalizing valve\n    \\item High-side bleed fitting\n    \\item Low-side bleed fitting\n\\end{enumerate}\n\n% ------------------------------------------------------------\n\\subsubsection{Normal Operation}\n\n\uc815\uc0c1 \uc6b4\uc804 \uc0c1\ud0dc\ub294 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{center}\n\\begin{tabular}{ll}\n\\toprule\nValve \/ Fitting &amp; \uc0c1\ud0dc \\\\\n\\midrule\nHigh-side block &amp; Open \\\\\nLow-side block &amp; Open \\\\\nEqualizing &amp; Closed \\\\\nHigh-side bleed &amp; Closed \\\\\nLow-side bleed &amp; Closed \\\\\n\\bottomrule\n\\end{tabular}\n\\end{center}\n\n\ub530\ub77c\uc11c H\uc640 L\uc758 pressure\uac00 \uac01\uac01 transmitter\uc5d0 \uc804\ub2ec\ub41c\ub2e4.\n\n\\&#91;\n\\Delta P=P_H-P_L\n\\]\n\n% ------------------------------------------------------------\n\\subsubsection{Normal $\\rightarrow$ Removed from Service}\n\n\uc815\uc0c1 \uc6b4\uc804 \uc911\uc778 DP transmitter\ub97c\nprocess\uc5d0\uc11c \uc548\uc804\ud558\uac8c \ubd84\ub9ac\ud560 \ub54c\uc758 \uc21c\uc11c\ub294 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\paragraph{Step 1. High-side block valve Close}\n\n\\&#91;\nH:\nOpen\n\\rightarrow\nClosed\n\\]\n\nH\uce21 process pressure\ub97c \ucc28\ub2e8\ud55c\ub2e4.\n\n\\paragraph{Step 2. Equalizing valve Open}\n\n\\&#91;\nE:\nClosed\n\\rightarrow\nOpen\n\\]\n\nH\uc640 L chamber\ub97c \uc5f0\uacb0\ud558\uc5ec\ntransmitter \uc591\ub2e8\uc758 differential pressure\ub97c \uc81c\uac70\ud55c\ub2e4.\n\n\\&#91;\nP_H\\approx P_L\n\\]\n\n\ub530\ub77c\uc11c\n\n\\&#91;\n\\Delta P\\approx 0\n\\]\n\n\uc774 \ub41c\ub2e4.\n\n\\paragraph{Step 3. Low-side block valve Close}\n\n\\&#91;\nL:\nOpen\n\\rightarrow\nClosed\n\\]\n\n\uc774\uc81c H\uce21\uacfc L\uce21 \ubaa8\ub450 process\ub85c\ubd80\ud130 \uaca9\ub9ac\ub41c\ub2e4.\n\n\\paragraph{Step 4. High \/ Low Bleed Open}\n\n\\&#91;\nB_H:\nClosed\n\\rightarrow\nOpen\n\\]\n\n\\&#91;\nB_L:\nClosed\n\\rightarrow\nOpen\n\\]\n\n\ub0b4\ubd80\uc5d0 \ub0a8\uc544 \uc788\ub294 pressure\ub97c \ubc30\ucd9c\ud55c\ub2e4.\n\n\ucd5c\uc885 Removed \uc0c1\ud0dc\ub294 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{center}\n\\begin{tabular}{ll}\n\\toprule\nValve \/ Fitting &amp; \uc0c1\ud0dc \\\\\n\\midrule\nHigh-side block &amp; Closed \\\\\nLow-side block &amp; Closed \\\\\nEqualizing &amp; Open \\\\\nHigh-side bleed &amp; Open \\\\\nLow-side bleed &amp; Open \\\\\n\\bottomrule\n\\end{tabular}\n\\end{center}\n\n\ub530\ub77c\uc11c \uc21c\uc11c\ub294\n\n\\&#91;\n\\boxed{\nH_C\n\\rightarrow\nE_O\n\\rightarrow\nL_C\n\\rightarrow\nB_O\n}\n\\]\n\n\uc774\ub2e4.\n\n\uc5ec\uae30\uc11c\n\n\\begin{itemize}\n    \\item $C$: Close\n    \\item $O$: Open\n    \\item $B$: High\/Low Bleed\n\\end{itemize}\n\n\uc774\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Removed from Service $\\rightarrow$ Normal}\n\n\uc815\uc0c1 \uc6b4\uc804 \ubcf5\uadc0\ub294 \uc704 \uacfc\uc815\uc758 \uc5ed\uc21c\uc774\ub2e4.\n\n\\paragraph{Step 1. High \/ Low Bleed Close}\n\n\\&#91;\nB_H:\nOpen\n\\rightarrow\nClosed\n\\]\n\n\\&#91;\nB_L:\nOpen\n\\rightarrow\nClosed\n\\]\n\n\ub300\uae30\ub85c \uc5f4\ub9b0 \uacbd\ub85c\ub97c \uba3c\uc800 \ucc28\ub2e8\ud55c\ub2e4.\n\n\\paragraph{Step 2. Low-side block valve Open}\n\n\\&#91;\nL:\nClosed\n\\rightarrow\nOpen\n\\]\n\nL\uce21 process pressure\ub97c transmitter\uc5d0 \uc804\ub2ec\ud55c\ub2e4.\n\nEqualizing valve\ub294 \uc544\uc9c1 \uc5f4\ub824 \uc788\uae30 \ub54c\ubb38\uc5d0\nH\uc640 L chamber\uc5d0 \ud070 differential pressure\uac00 \ubc1c\uc0dd\ud558\uc9c0 \uc54a\ub294\ub2e4.\n\n\\paragraph{Step 3. Equalizing valve Close}\n\n\\&#91;\nE:\nOpen\n\\rightarrow\nClosed\n\\]\n\nH\uc640 L chamber\ub97c \uc11c\ub85c \ubd84\ub9ac\ud55c\ub2e4.\n\n\\paragraph{Step 4. High-side block valve Open}\n\n\\&#91;\nH:\nClosed\n\\rightarrow\nOpen\n\\]\n\nH\uce21 pressure\uac00 transmitter\uc5d0 \uc804\ub2ec\ub418\uba74\uc11c\n\uc815\uc0c1\uc801\uc778 differential pressure \uce21\uc815\uc744 \uc2dc\uc791\ud55c\ub2e4.\n\n\ucd5c\uc885 Normal \uc0c1\ud0dc\ub294 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{center}\n\\begin{tabular}{ll}\n\\toprule\nValve \/ Fitting &amp; \uc0c1\ud0dc \\\\\n\\midrule\nHigh-side block &amp; Open \\\\\nLow-side block &amp; Open \\\\\nEqualizing &amp; Closed \\\\\nHigh-side bleed &amp; Closed \\\\\nLow-side bleed &amp; Closed \\\\\n\\bottomrule\n\\end{tabular}\n\\end{center}\n\n\ub530\ub77c\uc11c \ubcf5\uadc0 \uc21c\uc11c\ub294\n\n\\&#91;\n\\boxed{\nB_C\n\\rightarrow\nL_O\n\\rightarrow\nE_C\n\\rightarrow\nH_O\n}\n\\]\n\n\uc774\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Manifold \uc870\uc791 \uc21c\uc11c \uae30\uc5b5}\n\n\\begin{center}\n\\begin{tabularx}{0.95\\linewidth}{>{\\bfseries}l X}\n\\toprule\n\uc804\ud658 &amp; \uc870\uc791 \uc21c\uc11c \\\\\n\\midrule\n\nNormal $\\rightarrow$ Removed\n&amp;\nH Close\n$\\rightarrow$\nEqualize Open\n$\\rightarrow$\nL Close\n$\\rightarrow$\nH\/L Bleed Open\n\\\\\n\nRemoved $\\rightarrow$ Normal\n&amp;\nH\/L Bleed Close\n$\\rightarrow$\nL Open\n$\\rightarrow$\nEqualize Close\n$\\rightarrow$\nH Open\n\\\\\n\n\\bottomrule\n\\end{tabularx}\n\\end{center}\n\n\ucd5c\uc885 \uc0c1\ud0dc\ub9cc \uc678\uc6b0\uc9c0 \ub9d0\uace0\n\\key{\uc870\uc791 \uc21c\uc11c\uae4c\uc9c0 \uae30\uc5b5\ud574\uc57c \ud55c\ub2e4.}\n\n\\&#91;\n\\boxed{\n\\text{Normal}\n\\rightarrow\nH_C\n\\rightarrow\nE_O\n\\rightarrow\nL_C\n\\rightarrow\nB_O\n\\rightarrow\n\\text{Removed}\n}\n\\]\n\n\\&#91;\n\\boxed{\n\\text{Removed}\n\\rightarrow\nB_C\n\\rightarrow\nL_O\n\\rightarrow\nE_C\n\\rightarrow\nH_O\n\\rightarrow\n\\text{Normal}\n}\n\\]\n\n% ============================================================\n\\subsection{Bleed \/ Vent Fitting}\n\nBleed fitting\uc740 transmitter \ub610\ub294 pressure chamber \ub0b4\ubd80\uc758\n\uc555\ub825\uc744 \ub300\uae30\ub85c \ubc29\ucd9c\ud558\uae30 \uc704\ud574 \uc0ac\uc6a9\ud55c\ub2e4.\n\n\uc8fc\uc694 \ubaa9\uc801\uc740 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{enumerate}\n    \\item \uc720\uc9c0\ubcf4\uc218 \uc804 residual pressure \uc81c\uac70\n    \\item Zero-energy state \ud615\uc131\n    \\item Liquid process \ub0b4\ubd80\uc758 trapped gas \uc81c\uac70\n    \\item Gas process \ub0b4\ubd80\uc758 condensed liquid \uc81c\uac70\n    \\item Test pressure connection \uc81c\uacf5\n\\end{enumerate}\n\n% ------------------------------------------------------------\n\\subsubsection{Zero-Energy State}\n\nLive service \uc911\uc778 pressure transmitter\ub97c \uc81c\uac70\ud558\uae30 \uc804\uc5d0\n\ub0b4\ubd80\uc5d0 \ucd95\uc801\ub41c fluid pressure\ub97c atmosphere\ub85c vent\ud574\uc57c \ud55c\ub2e4.\n\n\uc989,\n\n\\&#91;\n\\boxed{\n\\text{Isolation}\n+\n\\text{Bleeding}\n\\rightarrow\n\\text{Zero-Energy State}\n}\n\\]\n\n\uc774\ub2e4.\n\n% ------------------------------------------------------------\n\\subsubsection{Bleed Fitting\uc758 \uc124\uce58 \uc704\uce58}\n\nLiquid process\uc5d0\uc11c air bubble\uc744 \uc81c\uac70\ud558\ub824\uba74\n\uae30\uccb4\uac00 \uc704\ucabd\uc5d0 \ubaa8\uc774\ubbc0\ub85c bleed fitting\uc744 \uc704\ucabd\uc5d0 \uc124\uce58\ud558\ub294 \uac83\uc774 \uc720\ub9ac\ud558\ub2e4.\n\n\\&#91;\n\\boxed{\nLiquid Process\n\\rightarrow\nGas Vent\n\\rightarrow\nUpper Position\n}\n\\]\n\nGas process\uc5d0\uc11c condensed liquid\ub97c \uc81c\uac70\ud558\ub824\uba74\n\uc561\uccb4\uac00 \uc544\ub798\ucabd\uc5d0 \ubaa8\uc774\ubbc0\ub85c\nbleed fitting\uc744 \uc544\ub798\ucabd\uc5d0 \uc124\uce58\ud558\ub294 \uac83\uc774 \uc720\ub9ac\ud558\ub2e4.\n\n\\&#91;\n\\boxed{\nGas Process\n\\rightarrow\nLiquid Drain\n\\rightarrow\nLower Position\n}\n\\]\n\n% ------------------------------------------------------------\n\\subsubsection{Stinger}\n\nBleed plug\ub97c \uc644\uc804\ud788 \uc81c\uac70\ud558\uba74\nbleed port\ub97c \uc2dc\ud5d8\uc555\ub825 \uc5f0\uacb0\uc6a9 port\ub85c \uc0ac\uc6a9\ud560 \uc218 \uc788\ub2e4.\n\n\uc774\ub54c \uc0ac\uc6a9\ud558\ub294\n\n\\begin{itemize}\n    \\item Bleed port adapter\n    \\item DP transmitter calibration fitting\n\\end{itemize}\n\n\uc744 \ud604\uc7a5\uc5d0\uc11c \ud754\ud788 \\key{stinger}\ub77c\uace0 \ud55c\ub2e4.\n\nStinger\ub97c \uc0ac\uc6a9\ud558\uba74 manifold bolt,\nimpulse tube fitting \ub4f1\uc744 \ubd84\ud574\ud558\uc9c0 \uc54a\uace0\ntest pressure\ub97c transmitter\uc5d0 \uac00\ud560 \uc218 \uc788\ub2e4.\n\n\\flow{\nHand Pump\n$\\rightarrow$\nTest Gauge\n$\\rightarrow$\nStinger\n$\\rightarrow$\nDP Transmitter\n}\n\n% ------------------------------------------------------------\n\\subsubsection{DP Transmitter Pressure Test \uc0c1\ud0dc}\n\nPressure test \uc0c1\ud0dc\uc5d0\uc11c\ub294\nprocess\uc640 transmitter\ub97c \uaca9\ub9ac\ud55c\ub2e4.\n\nBlock valve \uc0c1\ud0dc\ub294\n\n\\&#91;\nH=\\text{Closed}\n\\]\n\n\\&#91;\nL=\\text{Closed}\n\\]\n\n\uc774\ub2e4.\n\nDifferential pressure\ub97c \ud615\uc131\ud574\uc57c \ud558\ubbc0\ub85c\n\n\\&#91;\nEqualizing=\\text{Closed}\n\\]\n\n\uc774\ub2e4.\n\nH\uc640 L bleed port\ub294 \uc2dc\ud5d8 \uc5f0\uacb0 \ubc0f vent\ub97c \uc704\ud574 open \uc0c1\ud0dc\ub85c \ub454\ub2e4.\n\n\\begin{center}\n\\begin{tabular}{ll}\n\\toprule\nValve \/ Fitting &amp; Under Test \\\\\n\\midrule\nHigh-side block &amp; Closed \\\\\nLow-side block &amp; Closed \\\\\nEqualizing &amp; Closed \\\\\nHigh-side bleed &amp; Open \\\\\nLow-side bleed &amp; Open \\\\\n\\bottomrule\n\\end{tabular}\n\\end{center}\n\nH\uce21\uc5d0\ub294 hand pump\uc640 test gauge\ub97c \uc5f0\uacb0\ud55c\ub2e4.\n\nL\uce21\uc740 vent\ub418\uc5b4 reference pressure\ub97c \ud615\uc131\ud55c\ub2e4.\n\nEqualizing valve\ub97c \uc5f4\uc5b4 \ub450\uba74\n\n\\&#91;\nP_H=P_L\n\\]\n\n\uac00 \ub418\uc5b4\n\n\\&#91;\n\\Delta P=0\n\\]\n\n\uc774\ubbc0\ub85c DP pressure test\ub97c \uc218\ud589\ud560 \uc218 \uc5c6\ub2e4.\n\n% ============================================================\n\\subsection{Pressure Pulsation Damping}\n\nPump, compressor \ub4f1\uc5d0\uc11c\ub294\npressure\uac00 \uc9e7\uc740 \uc8fc\uae30\ub85c \ubc18\ubcf5 \ubcc0\ub3d9\ud560 \uc218 \uc788\ub2e4.\n\n\uc774\ub97c pressure pulsation\uc774\ub77c\uace0 \ud55c\ub2e4.\n\nPulsation\uc740 \ub2e4\uc74c \ubb38\uc81c\ub97c \ubc1c\uc0dd\uc2dc\ud0a8\ub2e4.\n\n\\begin{itemize}\n    \\item Gauge pointer vibration\n    \\item Measurement fluctuation\n    \\item Mechanical sensing element fatigue\n    \\item Instrument life \uac10\uc18c\n\\end{itemize}\n\nSnubber \ub610\ub294 damper\ub294\n\uc720\uccb4\uc758 \uc774\ub3d9\uc5d0 restriction\uc744 \uc8fc\uc5b4\n\ube60\ub978 pressure \ubcc0\ud654\uac00 instrument\uae4c\uc9c0 \uadf8\ub300\ub85c \uc804\ub2ec\ub418\uc9c0 \uc54a\uac8c \ud55c\ub2e4.\n\n\\flow{\nRapid Pressure Pulsation\n$\\rightarrow$\nRestriction\n$\\rightarrow$\nSmoothed Pressure\n}\n\nSignal \uad00\uc810\uc5d0\uc11c\ub294\n\n\\&#91;\n\\boxed{\\text{Low-Pass Filter\uc640 \uc720\uc0ac}}\n\\]\n\n\ud558\uac8c \uc774\ud574\ud560 \uc218 \uc788\ub2e4.\n\n\ub2e8, damping\uc774 \uc9c0\ub098\uce58\uac8c \ud06c\uba74\n\uc2e4\uc81c process pressure \ubcc0\ud654\uae4c\uc9c0 \ub290\ub9ac\uac8c \uc804\ub2ec\ub41c\ub2e4.\n\n\ub530\ub77c\uc11c\n\n\\&#91;\n\\boxed{\n\\text{Pulsation Reduction}\n\\leftrightarrow\n\\text{Response Speed}\n}\n\\]\n\n\uc0ac\uc774\uc5d0 trade-off\uac00 \uc788\ub2e4.\n\n% ============================================================\n\\subsection{Isolating Diaphragm \/ Process Isolation}\n\n\uc624\uc5fc\uc131 \ub610\ub294 \ubd80\uc2dd\uc131 process fluid\uac00\npressure sensor \ub0b4\ubd80\uc5d0 \uc9c1\uc811 \uc811\ucd09\ud558\ub294 \uac83\uc744 \ud53c\ud574\uc57c \ud560 \uc218 \uc788\ub2e4.\n\n\uc774 \uacbd\uc6b0 isolating diaphragm\uacfc fill fluid\ub97c \uc774\uc6a9\ud558\uc5ec\npressure\ub9cc \uc804\ub2ec\ud558\uace0 process fluid\ub294 \uaca9\ub9ac\ud560 \uc218 \uc788\ub2e4.\n\n\\flow{\nProcess Fluid\n$\\rightarrow$\nIsolating Diaphragm\n$\\rightarrow$\nFill Fluid\n$\\rightarrow$\nPressure Sensor\n}\n\n\uc989,\n\n\\&#91;\n\\boxed{\n\\text{Process Fluid\ub294 \ucc28\ub2e8}\n\\quad\n\\text{Pressure\ub294 \uc804\ub2ec}\n}\n\\]\n\n\ud558\ub294 \uad6c\uc870\uc774\ub2e4.\n\n% ============================================================\n\\section{\uc6a9\uc5b4 \uac04 \uad00\uacc4}\n\nChapter 19\ub294 \uac1c\ubcc4 sensor\ub97c \ub530\ub85c \uc554\uae30\ud558\ub294 \uac83\ubcf4\ub2e4\n\ubcc0\ud658 \uad00\uacc4\ub97c \uc911\uc2ec\uc73c\ub85c \uc774\ud574\ud558\ub294 \uac83\uc774 \uc911\uc694\ud558\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{\uc555\ub825\uc744 \ubb34\uc5c7\uc73c\ub85c \ubc14\uafb8\ub294\uac00?}\n\n\\begin{center}\n\\begin{tabularx}{0.96\\linewidth}{\n>{\\bfseries}l\nX}\n\\toprule\n\uc7a5\uce58 &amp; \ubcc0\ud658 \uad00\uacc4 \\\\\n\\midrule\n\nManometer\n&amp;\nPressure $\\rightarrow$ Liquid Height\n\\\\\n\nMechanical Element\n&amp;\nPressure $\\rightarrow$ Force \/ Displacement\n\\\\\n\nStrain Gauge\n&amp;\nPressure $\\rightarrow$ Strain $\\rightarrow$ Resistance\n\\\\\n\nCapacitance Sensor\n&amp;\nPressure $\\rightarrow$ Diaphragm Position $\\rightarrow$ Capacitance\n\\\\\n\nResonant Sensor\n&amp;\nPressure $\\rightarrow$ Force $\\rightarrow$ Frequency\n\\\\\n\nForce Balance\n&amp;\nPressure $\\rightarrow$ Force $\\rightarrow$ Counter Force\n\\\\\n\nDP Transmitter\n&amp;\n$P_H,\\;P_L\\rightarrow\\Delta P$\n\\\\\n\n\\bottomrule\n\\end{tabularx}\n\\end{center}\n\n% ------------------------------------------------------------\n\\subsection{\uc9c1\uc811 \uce21\uc815\uc5d0\uc11c \uac04\uc811 \uce21\uc815\uc73c\ub85c}\n\n\ucc98\uc74c\uc5d0\ub294 pressure \uc790\uccb4\ub97c \uce21\uc815\ud55c\ub2e4.\n\n\\&#91;\nP\n\\]\n\n\ub2e4\uc74c \ub2e8\uacc4\uc5d0\uc11c\ub294 \ub450 pressure\uc758 \ucc28\uc774\ub97c \uce21\uc815\ud55c\ub2e4.\n\n\\&#91;\n\\Delta P=P_H-P_L\n\\]\n\n\ub9c8\uc9c0\ub9c9\uc73c\ub85c \ubb3c\ub9ac \uad00\uacc4\uc2dd\uc744 \uc774\uc6a9\ud55c\ub2e4.\n\n\\&#91;\n\\Delta P\n\\rightarrow\nLevel,\\;Flow\n\\]\n\n\ub530\ub77c\uc11c\n\n\\&#91;\n\\boxed{\nPressure\n\\rightarrow\nDifferential Pressure\n\\rightarrow\nInferential Measurement\n}\n\\]\n\n\uc774\ub77c\ub294 \ud750\ub984\uc73c\ub85c \ubc1c\uc804\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Sensor\uc5d0\uc11c Measurement System\uc73c\ub85c}\n\n\uc815\ud655\ud55c pressure measurement\ub294\nsensor \ub2e8\ub3c5\uc758 \ubb38\uc81c\uac00 \uc544\ub2c8\ub2e4.\n\n\\&#91;\n\\boxed{\nSensor\n+\nProcess Connection\n+\nAccessories\n+\nOperating Procedure\n=\nReliable Measurement\n}\n\\]\n\n\uc774\ub2e4.\n\n\uac01 accessory\uc758 \uc5ed\ud560\uc740 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{center}\n\\begin{tabularx}{0.95\\linewidth}{\n>{\\bfseries}l\nX}\n\\toprule\n\uc7a5\uce58 &amp; \uc5ed\ud560 \\\\\n\\midrule\n\nManifold\n&amp;\nProcess \uc5f0\uacb0, isolation, equalization\n\\\\\n\nBleed \/ Vent\n&amp;\nResidual pressure \ubc0f trapped fluid \uc81c\uac70\n\\\\\n\nStinger\n&amp;\nField test pressure \uc5f0\uacb0\n\\\\\n\nDamper \/ Snubber\n&amp;\nPressure pulsation \uc644\ud654\n\\\\\n\nIsolating Diaphragm\n&amp;\nProcess fluid\uc640 sensing element \uaca9\ub9ac\n\\\\\n\n\\bottomrule\n\\end{tabularx}\n\\end{center}\n\n% ============================================================\n\\section{\uae30\uc5b5\uc744 \uc704\ud55c \uc2a4\ud1a0\ub9ac}\n\n\\subsection{Step 1. \uc555\ub825\uc744 \uac00\uc7a5 \ub2e8\uc21c\ud558\uac8c \uce21\uc815\ud55c\ub2e4}\n\nTank\uc5d0 pressure\uac00 \uc874\uc7ac\ud55c\ub2e4.\n\n\uac00\uc7a5 \ub2e8\uc21c\ud55c \ubc29\ubc95\uc740 \uc561\uc8fc\ub97c \uc5f0\uacb0\ud558\ub294 \uac83\uc774\ub2e4.\n\n\\&#91;\nP=\\rho gh\n\\]\n\nPressure\uac00 \ucee4\uc9c0\uba74 liquid height\uac00 \ubcc0\ud55c\ub2e4.\n\n\uc774\uac83\uc774 manometer\uc774\ub2e4.\n\n\uc5ec\uae30\uc11c gauge, differential, absolute pressure\uc758\n\uae30\uc900 \ucc28\uc774\ub97c \uc774\ud574\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Step 2. \uc561\uc8fc \ub300\uc2e0 \uae30\uacc4 \uad6c\uc870\ubb3c\uc744 \uc0ac\uc6a9\ud55c\ub2e4}\n\n\uc0b0\uc5c5\ud604\uc7a5\uc5d0\uc11c \uc561\uc8fc\ub97c \ud56d\uc0c1 \uc0ac\uc6a9\ud560 \uc218\ub294 \uc5c6\ub2e4.\n\n\ub530\ub77c\uc11c\n\n\\begin{itemize}\n    \\item Bourdon tube\n    \\item Diaphragm\n    \\item Bellows\n\\end{itemize}\n\n\ub4f1\uc744 \uc0ac\uc6a9\ud55c\ub2e4.\n\n\\&#91;\nP\n\\rightarrow\nF\n\\rightarrow\n\\text{Mechanical Deformation}\n\\]\n\n\uc73c\ub85c \ubcc0\ud658\ud55c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Step 3. \uae30\uacc4\uc801 \ubcc0\ud654\ub97c \uc804\uae30\uc2e0\ud638\ub85c \ubc14\uafbc\ub2e4}\n\nControl room\uae4c\uc9c0 \uce21\uc815\uac12\uc744 \uc804\ub2ec\ud558\uae30 \uc704\ud574\nelectrical sensor\uac00 \ud544\uc694\ud558\ub2e4.\n\n\\&#91;\n\\text{Strain}\n\\rightarrow\nR\n\\]\n\n\\&#91;\n\\text{Diaphragm Position}\n\\rightarrow\nC\n\\]\n\n\\&#91;\n\\text{Tension}\n\\rightarrow\nf\n\\]\n\n\uc989, \ud558\ub098\uc758 pressure\ub97c\n\uc11c\ub85c \ub2e4\ub978 electrical quantity\ub85c \ubcc0\ud658\ud560 \uc218 \uc788\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Step 4. Sensor\uac00 \ub9ce\uc774 \uc6c0\uc9c1\uc774\uc9c0 \uc54a\uac8c \ud55c\ub2e4}\n\nMechanical displacement\uac00 \ub9ce\uc73c\uba74\nspring characteristic \ub610\ub294 fatigue\uac00 \uce21\uc815\uc5d0 \uc601\ud5a5\uc744 \uc904 \uc218 \uc788\ub2e4.\n\n\ub530\ub77c\uc11c pressure\uac00 \ub9cc\ub4e0 \ud798\uc744\n\ubc18\ub300 \ud798\uc73c\ub85c \uc989\uc2dc \uc0c1\uc1c4\ud55c\ub2e4.\n\n\\&#91;\nF_{\\text{sensed}}\n=\nF_{\\text{balance}}\n\\]\n\nForce bar\uc758 position error\uac00 0\uc774 \ub418\uba74\nbalance\uac00 \uc774\ub8e8\uc5b4\uc9c4 \uac83\uc774\ub2e4.\n\n\uc774\ub54c \ud544\uc694\ud55c\n\n\\begin{itemize}\n    \\item Pneumatic pressure\n    \\item Electric current\n\\end{itemize}\n\n\uac00 pressure\uc758 \ud06c\uae30\ub97c \ub098\ud0c0\ub0b8\ub2e4.\n\n\uc774\uac83\uc774 force-balance transmitter\uc774\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Step 5. \ub450 \uc9c0\uc810\uc758 \uc555\ub825\ucc28\ub97c \uce21\uc815\ud55c\ub2e4}\n\n\uacf5\uc815\uc5d0\uc11c\ub294 \ub2e8\uc77c pressure\ubcf4\ub2e4\n\ub450 \uc9c0\uc810\uc758 \uc555\ub825\ucc28\uac00 \ud544\uc694\ud55c \uacbd\uc6b0\uac00 \ub9ce\ub2e4.\n\n\\&#91;\n\\Delta P=P_H-P_L\n\\]\n\nDP transmitter\ub85c \ucc28\uc555\uc744 \uce21\uc815\ud55c\ub2e4.\n\n\uadf8 \ud6c4 \ubb3c\ub9ac \uad00\uacc4\uc2dd\uc744 \uc774\uc6a9\ud55c\ub2e4.\n\n\\&#91;\nP=\\rho gh\n\\Rightarrow\nh=\\frac{P}{\\rho g}\n\\]\n\n\\&#91;\nQ\\propto\\sqrt{\\Delta P}\n\\]\n\n\ub530\ub77c\uc11c pressure measurement\uac00\nlevel\uacfc flow measurement\ub85c \ud655\uc7a5\ub41c\ub2e4.\n\n% ------------------------------------------------------------\n\\subsection{Step 6. \uc2e4\uc81c \ud604\uc7a5\uc5d0 \uc124\uce58\ud55c\ub2e4}\n\n\uc2e4\uc81c process\uc5d0\ub294\n\n\\begin{itemize}\n    \\item Pulsation\n    \\item Vibration\n    \\item Trapped gas\n    \\item Condensed liquid\n    \\item Residual pressure\n    \\item Corrosive fluid\n    \\item Contamination\n\\end{itemize}\n\n\uc774 \uc874\uc7ac\ud55c\ub2e4.\n\n\ub530\ub77c\uc11c transmitter\ub9cc \uc124\uce58\ud574\uc11c\ub294 \ucda9\ubd84\ud558\uc9c0 \uc54a\ub2e4.\n\n\\flow{\nProcess\n$\\rightarrow$\nManifold \/ Bleed \/ Damper \/ Isolation\n$\\rightarrow$\nPressure Transmitter\n$\\rightarrow$\nSignal\n$\\rightarrow$\nControl System\n}\n\n% ------------------------------------------------------------\n\\subsection{Step 7. \uc720\uc9c0\ubcf4\uc218\ub97c \uc704\ud574 \uc548\uc804\ud558\uac8c \ubd84\ub9ac\ud55c\ub2e4}\n\nDP transmitter\ub97c \ubd84\ub9ac\ud560 \ub54c\ub294\n\ub2e8\uc21c\ud788 \ub450 block valve\ub97c \ub3d9\uc2dc\uc5d0 \ub2eb\ub294 \uac83\uc73c\ub85c \ub05d\ub098\uc9c0 \uc54a\ub294\ub2e4.\n\n\uc815\ud655\ud55c \uc21c\uc11c\ub294\n\n\\&#91;\n\\boxed{\nH_C\n\\rightarrow\nE_O\n\\rightarrow\nL_C\n\\rightarrow\nB_O\n}\n\\]\n\n\uc774\ub2e4.\n\n\uc815\uc0c1 \ubcf5\uadc0\ub294 \uc5ed\uc21c\uc774\ub2e4.\n\n\\&#91;\n\\boxed{\nB_C\n\\rightarrow\nL_O\n\\rightarrow\nE_C\n\\rightarrow\nH_O\n}\n\\]\n\n\uc774 \uc21c\uc11c\ub97c \ud1b5\ud574 transmitter\ub97c\nprocess\ub85c\ubd80\ud130 \uaca9\ub9ac\ud558\uace0,\ndifferential pressure\uc640 residual pressure\ub97c \uc81c\uac70\ud55c\ub2e4.\n\n% ============================================================\n\\section{Chapter 19 \ud575\uc2ec \uae30\uc5b5 \ubb38\uc7a5}\n\n\\begin{enumerate}\n\n\\item\n\\textbf{\nPressure\ub294 \ud798\uacfc \ubcc0\ud615\uc744 \ub9cc\ub4e4\uace0,\nsensor\ub294 \uc774\ub97c $R$, $C$, $f$ \ub610\ub294 balancing force\ub85c \ubcc0\ud658\ud55c\ub2e4.\n}\n\n\\item\n\\textbf{\nDP transmitter\ub294 $P_H-P_L$\ub97c \uce21\uc815\ud558\uba70,\n\ucc28\uc555\uc744 \uc774\uc6a9\ud558\uc5ec level\uacfc flow \ub4f1\uc744 \uac04\uc811 \uce21\uc815\ud560 \uc218 \uc788\ub2e4.\n}\n\n\\item\n\\textbf{\nForce-balance\ub294 \ud798 \uc790\uccb4\ub97c \uc9c1\uc811 \uce21\uc815\ud558\ub294 \uac83\uc774 \uc544\ub2c8\ub77c,\n\ubd88\uade0\ud615\uc73c\ub85c \ubc1c\uc0dd\ud55c position error\ub97c 0\uc73c\ub85c \ub9cc\ub4dc\ub294 \ub370 \ud544\uc694\ud55c\ncounter-force\ub97c \uce21\uc815\ud55c\ub2e4.\n}\n\n\\item\n\\textbf{\n\uc815\ud655\ud55c pressure measurement\ub294 transmitter\ub9cc\uc758 \ubb38\uc81c\uac00 \uc544\ub2c8\ub77c,\nmanifold, bleed, damping, isolation\uacfc\n\uc62c\ubc14\ub978 valve operating sequence\ub97c \ud3ec\ud568\ud55c \uc804\uccb4 \uc2dc\uc2a4\ud15c\uc758 \ubb38\uc81c\uc774\ub2e4.\n}\n\n\\end{enumerate}\n\n% ============================================================\n\\section{\ucd5c\uc885 \uc554\uae30 \uad6c\uc870}\n\n\\&#91;\n\\boxed{\n\\begin{array}{c}\n\\text{Pressure} \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\n\\text{Liquid Height \/ Force \/ Deformation} \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\nR,\\;C,\\;f,\\;\\text{Force Balance} \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\n\\text{Pressure Transmitter} \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\n\\Delta P \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\n\\text{Level \/ Flow Inference} \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\n\\text{Manifold \/ Bleed \/ Damping \/ Isolation} \\\\&#91;2mm]\n\\downarrow \\\\&#91;2mm]\n\\text{Reliable Field Measurement}\n\\end{array}\n}\n\\]\n\n\\vspace{1em}\n\nChapter 19 \uc804\uccb4\ub97c \ud55c \ubb38\uc7a5\uc73c\ub85c \uc815\ub9ac\ud558\uba74 \ub2e4\uc74c\uacfc \uac19\ub2e4.\n\n\\begin{quote}\n\\textbf{\n\uc555\ub825\uc744 \uc561\uc8fc, \uae30\uacc4\uc801 \ubcc0\ud615, \uc800\ud56d, \uc815\uc804\uc6a9\ub7c9, \uacf5\uc9c4\uc8fc\ud30c\uc218 \ub610\ub294\nforce balance\ub85c \uce21\uc815\ud558\uace0,\n\ucc28\uc555\uc744 \uc774\uc6a9\ud558\uc5ec \ub2e4\ub978 \uacf5\uc815\ubcc0\uc218\uae4c\uc9c0 \ucd94\uc815\ud558\uba70,\n\ud604\uc7a5\uc5d0\uc11c\ub294 manifold\uc640 \uac01\uc885 accessory\ub97c \uc774\uc6a9\ud558\uc5ec\n\uc548\uc804\ud558\uace0 \uc2e0\ub8b0\uc131 \uc788\ub294 pressure measurement system\uc744 \uad6c\uc131\ud55c\ub2e4.\n}\n\\end{quote}\n\n\\end{document}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Chapter 19. Continuous Pressure Measurement \uc6a9\uc5b4 \uc815\uc758 \u2192 \uc6a9\uc5b4 \uac04 \uad00\uacc4 \u2192 \uc2a4\ud1a0\ub9ac \u2192 \ud604\uc7a5 \uc801\uc6a9 1. Chapter 19 \uc804\uccb4 \ud750\ub984 \uacf5\uc815\uc758 \uc555\ub825\uc744 \uc5b4\ub5bb\uac8c \uac10\uc9c0\ud558\uace0, \uce21\uc815 \uac00\ub2a5\ud55c \ubb3c\ub9ac\ub7c9\uc73c\ub85c \ubcc0\ud658\ud558\uba70, \uc804\uae30 \ub610\ub294 \uacf5\uc555 \uc2e0\ud638\ub85c \uc804\ub2ec\ud558\uace0, \uc2e4\uc81c \ud604\uc7a5\uc5d0\uc11c \uc815\ud655\ud558\uace0 \uc548\uc804\ud558\uac8c \uce21\uc815\ud560 \uac83\uc778\uac00? Pressure \u2192 Liquid Height \/ Mechanical Force \u2192 Electrical Quantity \u2192 Pressure Transmitter \u2192 Differential [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[1185],"tags":[2184],"class_list":["post-9499","post","type-post","status-publish","format-standard","hentry","category-1185","tag-pressure-accessories"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/posts\/9499","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/comments?post=9499"}],"version-history":[{"count":7,"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/posts\/9499\/revisions"}],"predecessor-version":[{"id":9514,"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/posts\/9499\/revisions\/9514"}],"wp:attachment":[{"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/media?parent=9499"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/categories?post=9499"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/now0930.pe.kr\/wordpress\/wp-json\/wp\/v2\/tags?post=9499"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}