Emerson Process Management 53eA Temp coeff, Operate iso 7.00 pH Sensor iso 7.00 pH

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MODEL 54eA

SECTION 5.0

 

SOFTWARE CONFIGURATION

5.8 CONFIGURING THE pH MEASUREMENT (continued)

pH diagnostics pH calibration Temperature coeff

ExitEnter

Temp coeff : 0.000

Operate iso: 7.00 pH

Sensor iso: 7.00 pH

ExitEnter

Stabilize pH and Stabilize time: For the controller to accept cal- ibration data, the pH must remain within a specified range for a specified period of time. The default values are 0.01 pH for 10 sec- onds. Using a small pH value and a large time provides the best protection against calibration while the reading is still changing.

8.In many industries pH is used and reported at a reference tempera- ture of 25°C. Correcting a pH reading to 25°C is often referred to as a solution temperature correction. To perform the correction, the solu- tion temperature coefficient must be known.

a. With the cursor on "Temperature coeff", press Enter (F4).

b.Use the é and ê keys to move through the list of items. To make a change press Edit (F4). Use the arrow keys to change the set- ting to the desired value and press Save (F4). For allowed ranges see Table 5-1.

Temp coeff: Enter the temperature coefficient in units of ΔpH/°C. If the pH decreases as temperature increases, the temperature coefficient is negative. The temperature coefficient must usually be determined empirically.

APPLICATION WARNING

If pH is being measured for the purposes of correct- ing a free chlorine reading, do NOT use solution tem- perature correction. Keep the temperature coeffi- cient at 0.000 pH/°C.

Operate iso: Entering a temperature coefficient ALWAYS causes the operating isopotential to change from the normal value of

7.00.When programming the controller to perform solution tem- perature compensation, ALWAYS enter the solution temperature coefficient and allow the transmitter to calculate the operating isopotential pH.

Sensor iso: The isopotential pH is the pH at which the cell volt- age is independent of temperature. Most sensors have an isopo- tential pH fairly close to 7.0, so the default value is 7.00. Certain specialized pH electrodes have isopotential pH significantly dif- ferent from 7.0.

NOTE

Do NOT change the isopotential pH of the con- troller unless you are thoroughly familiar with the role of isopotential points in pH measurements OR the sensor operating instructions specifically state the isopotential pH is a value other than pH 7.

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Contents Model 54eA Amperometric Hart Analyzer/ControllerEssential Instructions Page Model 54eA ANALYZER/CONTROLLER 12.0 10.011.0 13.0Section Title List of FiguresIii Section Specifications Features and ApplicationsOutput Accuracy ± 0.05 mA Alarms Specifications GeneralPower Weight/Shipping Weight 5 lb/6 lb 2 kg/2.5 kgSpecifications Total Chlorine Specifications OxygenSpecifications Free Chlorine Specifications OzoneOrdering Information 115/230 VAC, 50/60 Hz Power24 VDC Installation Section InstallationUnpacking and Inspection Pipe and Wall Mounting Dimensions Pipe mountingPanel Mounting Dimensions Panel mountingPOWER, ALARM, and Output Wiring Section WiringGeneral 454EPH02 Wiring Model 499A oxygen, chlorine, and ozone sensors Sensor WiringGeneral 4054eA01 4054eA03 4054eA02 4054eA04 4054eA07 General Description Alarm StatusSection Display and Operation DisplaySection Software Configuration Program Settings ListChoices Factory Settings Configure Choices Factory Settings Temperature compensation Section Menu Tree for the 54eA Controller Main Menu Main Alarm setpoints Alarm 2 setpointMA 0.00 ppm 20 mA 20.00 ppm Output 1 12.00 mA Ranging the OutputsSimulated test Alarm setpointsOutput setpoints Setpoint 1.000 ppm 4mA 0.000 ppm 20mA 10.00 ppmSimulated tests Test alarm 1 OpenTest output Configure DisplayTemp units C Output 1 mA Output 2 mA Display contrast Timeout OnLanguage English Display left Display right Out Output 1 control OutputsOutput Measurement Output 1 Control Ctrl mode NormalOutput 1 Setup Range 4-20 mA Dampen 0 sec Hold Last ValueHold setup Using holdChanges in the alarm setup Changing Alarm ParametersAlways configure the control parameters Before making Alarm Control SettingsAlarm 2 control Alarm 1 controlAlarm 1 setup Alarm Low Setpoint 0.000 ppmLow Alarm High AlarmTimeout 3600 sec Alarm FaultFeed limit Disable Feed limit timer setupTimer Disable Timer Time activated Interval 24.0 hr Alarm 4 setup Feed limit timerInterval timer Interval timer setupUsing the 499ACL-01 sensor PH sensor EnablePH sensor Disable PH comp Manual PH value 7.00 pHGlass imp lo 20 MΩ Diagnostics OffAutocal Standard Temp coeff Operate iso 7.00 pH Sensor iso 7.00 pHTemp units C Temperature Compensation and Temperature UnitsTemp comp Auto Temp comp Manual Temp units C60 Hz Noise ReductionMain sensor cal Bar units mm Hg Bar meas AutoBarometric Pressure Security Lock program Lock configNoise rejection Main sensor cal Lock allCondition Definitions Controller Mode PriorityAction Definitions Section Calibration Temperature IntroductionAdjust temp + 025.1 C Temperature CalibrationSection Calibration Dissolved Oxygen Dissolved Oxygen ConcentrationSensor must be in zero solution Zeroing the SensorStabilizing . . . Wait Calibrating the Sensor in AIRSection Calibrate 8.32 ppm Calibrating the Sensor Against a Standard InstrumentStandardize Zero main sensor Adjust temperatureCalibrate main sensor Calibrating Barometric PressureSection Calibration Free Chlorine 499ACL-01 Sensor Current as a Function of Free Chlorine ConcentrationCalibrate main sensor Calibrate 1.100 ppm Full Scale CalibrationCalibrate low point Dual range calOutput trim Dual Slope CalibrationLow point 2.000 ppm Calibrate high pointSection Calibration Free Chlorine 498CL-01 IntroductionPpm 100ppm 000 ppm Section Calibration Free Chlorine 498CL-01 Section Calibration Total Chlorine This page intentionally left blank Section Calibration Monochloramine Sensor Current as a Function of Monochloramine ConcentrationPpm 100ppm Section Calibration Ozone Sensor Current as a Function of Ozone ConcentrationPpm 100ppm Section PH at 25C Standards Nominal pHAutocal buffer Automatic TWO-POINT Calibration10.02 pH Pt 04.00pH 25C Calibrate pointManual TWO-POINT Calibration 10.01 pH Pt 4.00pH 25.0CStandardization ONE-POINT Calibration Pt calibration Standardize pH pH slopePH slope 60.00 mV/pH Section Calibration Current Outputs Trimming the OutputsSection PID and TPC Control PID Control CodeControl Loop Adjustment and Tuning Proportional Gain Plus Integral ResetProcess Reaction Curve Method Process Reaction Curve Section Time Proportional Control TPC Mode Code Fault message Explanation See Section Section TroubleshootingTroubleshooting When a Fault Message is Showing OverviewCheck sensor zero Temperature error low or highHigh input current PH low or high input voltageSense line open Troubleshooting When no Fault Message is Showing OxygenProblem See Section Failure factory and Failure eepromZero current is too high Possible error warning during in-process calibrationZero reading Is unstable Readings drift Barometric pressure reading is too high or too lowProcess readings are erratic Sensor does not respond to changes in oxygen levelProblem Zero current is unstableSensor can be calibrated, but the current is too low Sensor does not respond to changes in chlorine level Chlorine readings are too lowProblem See Section Sensor does not respond to changes in monochloramine level Readings are too low Troubleshooting When no Fault Message is Showing Ozone Sensor does not respond to changes in ozone level Ozone readings are too lowTroubleshooting When no Fault Message is Showing pH Sensor does not respond to known pH changes Controller will not accept manual slope100 Process pH readings are noisy 101Simulating Inputs Dissolved Oxygen Troubleshooting not Related to Measurement ProblemsProblem Action Sensor Polarizing Voltage Resistance Expected currentSimulating Inputs Other Amperometric Measurements Simulate Chlorine and Ozone 103Voltage mV PH at 25C Simulating pH input when the preamplifier is in the sensor104 Simulating temperature Simulating Temperature105 Measuring Reference Voltage 106Section Maintenance Replacement Parts Part Number DescriptionSection Return of Material GeneralWarranty Specifications subject to change without notice