Emerson Process Management 53eA Simulating Temperature, Simulating temperature, 105

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MODEL 54eA

SECTION 16.0

 

TROUBLESHOOTING

16.14 SIMULATING TEMPERATURE

16.14.1 General.

The 54eA controller accepts either a Pt100 RTD (for pH, 499ADO, 499ATrDO, 499ACL-01, 499ACL-02, 499ACL-03, and 499AOZ sensors) or a 22k NTC thermistor (for Hx438 and Gx448 DO sensors and most steam-sterilizable DO sensors from other manufacturers). The Pt100 RTD is in a three-wire configuration. See Figure 16-4. The 22k ther- mistor has a two-wire configuration.

16.14.2 Simulating temperature

To simulate the temperature input, wire a decade box to the analyzer or junction box as shown in Figure 16-5.

To check the accuracy of the temperature measurement, set the resistor simulating the RTD to the values indicated in the table and note the temperature readings. The meas- ured temperature might not agree with the value in the table. During sensor calibration an offset might have been applied to make the measured temperature agree with a standard thermometer. The offset is also applied to the simulated resistance. The controller is measuring tempera- ture correctly if the difference between measured tempera- tures equals the difference between the values in the table to within ±0.1°C.

For example, start with a simulated resistance of 103.9 Ω, which corresponds to 10.0°C. Assume the offset from the sensor calibration was -0.3 Ω. Because of the offset, the analyzer calculates temperature using 103.6 Ω. The result is 9.2°C. Now change the resistance to 107.8 Ω, which cor- responds to 20.0°C. The analyzer uses 107.5 Ω to calcu- late the temperature, so the display reads 19.2°C. Because the difference between the displayed temperatures (10.0°C) is the same as the difference between the simu- lated temperatures, the analyzer is working correctly.

FIGURE 16-4. Three-Wire RTD Configuration.

Although only two wires are required to connect the RTD to the analyzer, using a third (and sometimes fourth) wire allows the analyzer to correct for the resistance of the lead wires and for changes in the lead wire resistance with temperature.

FIGURE 16-5. Simulating RTD Inputs.

The figure shows wiring connections for sensors con- taining a Pt 100 RTD. For sensors using a 22k NTC ther- mistor (Hx438 and Gx448 sensors), wire the decade box to terminals 1 and 3 on TB6.

 

Temp. (°C)

Pt 100 (Ω)

22k NTC (kΩ)

 

 

0

100.0

64.88

 

 

10

103.9

41.33

 

 

20

107.8

26.99

 

 

25

109.7

22.00

 

 

30

111.7

18.03

 

 

40

115.5

12.31

 

 

50

119.4

8.565

 

 

60

123.2

6.072

 

 

70

127.1

4.378

 

 

80

130.9

3.208

 

 

85

132.8

2.761

 

 

90

134.7

2.385

 

100

138.5

1.798

 

 

 

 

 

 

105

Image 111
Contents Amperometric Hart Analyzer/Controller Model 54eAEssential Instructions Page Model 54eA ANALYZER/CONTROLLER 13.0 10.011.0 12.0List of Figures Section TitleIii Features and Applications Section SpecificationsWeight/Shipping Weight 5 lb/6 lb 2 kg/2.5 kg Specifications GeneralPower Output Accuracy ± 0.05 mA AlarmsSpecifications Ozone Specifications OxygenSpecifications Free Chlorine Specifications Total Chlorine115/230 VAC, 50/60 Hz Power Ordering Information24 VDC Section Installation InstallationUnpacking and Inspection Pipe mounting Pipe and Wall Mounting DimensionsPanel mounting Panel Mounting DimensionsSection Wiring POWER, ALARM, and Output WiringGeneral 454EPH02 Sensor Wiring Wiring Model 499A oxygen, chlorine, and ozone sensorsGeneral 4054eA01 4054eA03 4054eA02 4054eA04 4054eA07 Display Alarm StatusSection Display and Operation General DescriptionProgram Settings List Section Software ConfigurationChoices Factory Settings Configure Choices Factory Settings Temperature compensation Section Menu Tree for the 54eA Controller Main Menu Main Alarm 2 setpoint Alarm setpointsRanging the Outputs MA 0.00 ppm 20 mA 20.00 ppm Output 1 12.00 mASetpoint 1.000 ppm 4mA 0.000 ppm 20mA 10.00 ppm Alarm setpointsOutput setpoints Simulated testTest alarm 1 Open Simulated testsTest output Display ConfigureDisplay contrast Timeout On Temp units C Output 1 mA Output 2 mALanguage English Display left Display right Out Outputs Output 1 controlOutput Measurement Range 4-20 mA Dampen 0 sec Hold Last Value Ctrl mode NormalOutput 1 Setup Output 1 ControlUsing hold Hold setupAlarm Control Settings Changing Alarm ParametersAlways configure the control parameters Before making Changes in the alarm setupAlarm Low Setpoint 0.000 ppm Alarm 1 controlAlarm 1 setup Alarm 2 controlHigh Alarm Low AlarmFeed limit timer setup Alarm FaultFeed limit Disable Timeout 3600 secInterval timer setup Alarm 4 setup Feed limit timerInterval timer Timer Disable Timer Time activated Interval 24.0 hrPH comp Manual PH value 7.00 pH PH sensor EnablePH sensor Disable Using the 499ACL-01 sensorDiagnostics Off Glass imp lo 20 MΩAutocal Standard Operate iso 7.00 pH Sensor iso 7.00 pH Temp coeffTemp comp Manual Temp units C Temperature Compensation and Temperature UnitsTemp comp Auto Temp units CNoise Reduction 60 HzMain sensor cal Bar meas Auto Bar units mm HgBarometric Pressure Lock all Lock program Lock configNoise rejection Main sensor cal SecurityController Mode Priority Condition DefinitionsAction Definitions Introduction Section Calibration TemperatureTemperature Calibration Adjust temp + 025.1 CDissolved Oxygen Concentration Section Calibration Dissolved OxygenZeroing the Sensor Sensor must be in zero solutionCalibrating the Sensor in AIR Stabilizing . . . WaitSection Calibrating the Sensor Against a Standard Instrument Calibrate 8.32 ppmCalibrating Barometric Pressure Zero main sensor Adjust temperatureCalibrate main sensor StandardizeSensor Current as a Function of Free Chlorine Concentration Section Calibration Free Chlorine 499ACL-01Calibrate main sensor Full Scale Calibration Calibrate 1.100 ppmDual Slope Calibration Dual range calOutput trim Calibrate low pointCalibrate high point Low point 2.000 ppmIntroduction Section Calibration Free Chlorine 498CL-01Ppm 100ppm 000 ppm Section Calibration Free Chlorine 498CL-01 Section Calibration Total Chlorine This page intentionally left blank Sensor Current as a Function of Monochloramine Concentration Section Calibration MonochloraminePpm 100ppm Sensor Current as a Function of Ozone Concentration Section Calibration OzonePpm 100ppm PH at 25C Standards Nominal pH SectionAutomatic TWO-POINT Calibration Autocal buffer10.02 pH Calibrate point Pt 04.00pH 25CManual TWO-POINT Calibration Pt 4.00pH 25.0C 10.01 pHPt calibration Standardize pH pH slope Standardization ONE-POINT CalibrationPH slope 60.00 mV/pH Trimming the Outputs Section Calibration Current OutputsPID Control Code Section PID and TPC ControlProportional Gain Plus Integral Reset Control Loop Adjustment and TuningProcess Reaction Curve Method Process Reaction Curve Section Time Proportional Control TPC Mode Code Overview Section TroubleshootingTroubleshooting When a Fault Message is Showing Fault message Explanation See SectionPH low or high input voltage Temperature error low or highHigh input current Check sensor zeroFailure factory and Failure eeprom Troubleshooting When no Fault Message is Showing OxygenProblem See Section Sense line openPossible error warning during in-process calibration Zero current is too highZero reading Is unstable Sensor does not respond to changes in oxygen level Barometric pressure reading is too high or too lowProcess readings are erratic Readings driftZero current is unstable ProblemSensor can be calibrated, but the current is too low Chlorine readings are too low Sensor does not respond to changes in chlorine levelProblem See Section Sensor does not respond to changes in monochloramine level Readings are too low Troubleshooting When no Fault Message is Showing Ozone Ozone readings are too low Sensor does not respond to changes in ozone levelTroubleshooting When no Fault Message is Showing pH Controller will not accept manual slope Sensor does not respond to known pH changes100 101 Process pH readings are noisySensor Polarizing Voltage Resistance Expected current Troubleshooting not Related to Measurement ProblemsProblem Action Simulating Inputs Dissolved OxygenSimulate Chlorine and Ozone 103 Simulating Inputs Other Amperometric MeasurementsSimulating pH input when the preamplifier is in the sensor Voltage mV PH at 25C104 Simulating Temperature Simulating temperature105 106 Measuring Reference VoltageReplacement Parts Part Number Description Section MaintenanceGeneral Section Return of MaterialWarranty Specifications subject to change without notice