Emerson Process Management 53eA Sensor must be in zero solution, Zeroing the Sensor

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MODEL 54eA

SECTION 7.0

 

CALIBRATION - DISSOLVED OXYGEN

7.2ZEROING THE SENSOR

1.Place the sensor in a fresh solution of 5% sodium sulfite (Na2SO3) in water. Be sure air bubbles are not trapped against the membrane. The current will drop rapidly at first and then gradually reach a stable zero

value. To monitor the sensor current, go to the main display. Press any key to obtain the main menu. Press

the ê key once to highlight “Diagnostic variables.” Press Enter (F4). The sensor current is the second item in the display. Note the units: nA is nanoamps, μA is microamps. To return to the main display, press exit (F1) twice.The table gives typical zero currents for Rosemount Analytical sensors.

 

Sensor

Zero current (nA)

 

 

499ADO

<50 nA

 

 

499A TrDO

<5 nA

 

 

Hx438 and Gx448

<1 nA

 

 

 

 

The Model 499A TrDO does not normally require zeroing.

A new sensor or a sensor in which the electrolyte solution has been replaced may require several hours (occa- sionally as long as overnight) to reach a minimum current. DO NOT START THE ZERO ROUTINE UNTIL THE SENSOR HAS BEEN IN ZERO SOLUTION FOR AT LEAST TWO HOURS.

Calibrate main sensor Zero main sensor Adjust temperature

ExitEnter

2.From the main display, press any key to obtain the main menu. With the cursor on “Calibrate,” press Enter (F4).

NOTE

If Hold was enabled in Section 5.6, the hold screen will appear. To activate hold, refer to Section 5.6, step 11.

3.Press the ê key once to move the cursor to “Zero main sensor.” Press Enter (F4).

0.0 ppm

Sensor must be in zero solution

Abort Cont

4.The screen at left appears. Press Cont (F3). “Wait” flashes until the sensor is stabilized. Once the zero step is complete, the message “Sensor zero done” appears.

5.Press Exit (F1) three times to return to the main display.

NOTE

If Hold was activated during calibration, “Hold Mode Activated” will continue to flash in the main display. Return the sensor to normal and deactivate Hold. Refer to Section 5.6, step 11.

NOTE

During calibration, ERROR and WARNING messages may appear. If an ERROR message appears, press Exit (F1) to leave and return to the previous screen. If a WARNING message appears, press Cont (F3) to continue the calibration or press Abort (F1) to leave. Continuing the calibration after a warning message appears may cause substantial errors in the subsequent measurement. Refer to Section 15.4 for assis- tance.

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Contents Model 54eA Amperometric Hart Analyzer/ControllerEssential Instructions Page Model 54eA ANALYZER/CONTROLLER 10.0 11.012.0 13.0Iii List of FiguresSection Title Section Specifications Features and ApplicationsSpecifications General PowerOutput Accuracy ± 0.05 mA Alarms Weight/Shipping Weight 5 lb/6 lb 2 kg/2.5 kgSpecifications Oxygen Specifications Free ChlorineSpecifications Total Chlorine Specifications Ozone24 VDC 115/230 VAC, 50/60 Hz PowerOrdering Information Unpacking and Inspection Section InstallationInstallation Pipe and Wall Mounting Dimensions Pipe mountingPanel Mounting Dimensions Panel mountingGeneral Section WiringPOWER, ALARM, and Output Wiring 454EPH02 General Sensor WiringWiring Model 499A oxygen, chlorine, and ozone sensors 4054eA01 4054eA03 4054eA02 4054eA04 4054eA07 Alarm Status Section Display and OperationGeneral Description 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 OutputsAlarm setpoints Output setpointsSimulated test Setpoint 1.000 ppm 4mA 0.000 ppm 20mA 10.00 ppmTest output Test alarm 1 OpenSimulated tests Configure DisplayLanguage English Display left Display right Out Display contrast Timeout OnTemp units C Output 1 mA Output 2 mA Output Measurement OutputsOutput 1 control Ctrl mode Normal Output 1 SetupOutput 1 Control Range 4-20 mA Dampen 0 sec Hold Last ValueHold setup Using holdChanging Alarm Parameters Always configure the control parameters Before makingChanges in the alarm setup Alarm Control SettingsAlarm 1 control Alarm 1 setupAlarm 2 control Alarm Low Setpoint 0.000 ppmLow Alarm High AlarmAlarm Fault Feed limit DisableTimeout 3600 sec Feed limit timer setupAlarm 4 setup Feed limit timer Interval timerTimer Disable Timer Time activated Interval 24.0 hr Interval timer setupPH sensor Enable PH sensor DisableUsing the 499ACL-01 sensor PH comp Manual PH value 7.00 pHAutocal Standard Diagnostics OffGlass imp lo 20 MΩ Temp coeff Operate iso 7.00 pH Sensor iso 7.00 pHTemperature Compensation and Temperature Units Temp comp AutoTemp units C Temp comp Manual Temp units C60 Hz Noise ReductionMain sensor cal Barometric Pressure Bar meas AutoBar units mm Hg Lock program Lock config Noise rejection Main sensor calSecurity Lock allAction Definitions Controller Mode PriorityCondition 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 InstrumentZero main sensor Adjust temperature Calibrate main sensorStandardize 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 CalibrationDual range cal Output trimCalibrate low point 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 Manual TWO-POINT Calibration Calibrate pointPt 04.00pH 25C 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 CodeProcess Reaction Curve Method Proportional Gain Plus Integral ResetControl Loop Adjustment and Tuning Process Reaction Curve Section Time Proportional Control TPC Mode Code Section Troubleshooting Troubleshooting When a Fault Message is ShowingFault message Explanation See Section OverviewTemperature error low or high High input currentCheck sensor zero PH low or high input voltageTroubleshooting When no Fault Message is Showing Oxygen Problem See SectionSense line open Failure factory and Failure eepromZero reading Is unstable Possible error warning during in-process calibrationZero current is too high Barometric pressure reading is too high or too low Process readings are erraticReadings drift 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 100 Controller will not accept manual slopeSensor does not respond to known pH changes Process pH readings are noisy 101Troubleshooting not Related to Measurement Problems Problem ActionSimulating Inputs Dissolved Oxygen Sensor Polarizing Voltage Resistance Expected currentSimulating Inputs Other Amperometric Measurements Simulate Chlorine and Ozone 103104 Simulating pH input when the preamplifier is in the sensorVoltage mV PH at 25C 105 Simulating TemperatureSimulating temperature Measuring Reference Voltage 106Section Maintenance Replacement Parts Part Number DescriptionSection Return of Material GeneralWarranty Specifications subject to change without notice
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