Emerson Process Management 53eA instruction manual Problem See Section

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MODEL 54eA	SECTION 16.0
	TROUBLESHOOTING

16.7TROUBLESHOOTING WHEN NO ERROR MESSAGE IS SHOWING — MONOCHLORAMINE

	Problem	See Section
	Zero current was accepted, but the current is outside the range -10 to 50 nA	16.7.1
	Error or warning message appears while zeroing the sensor (zero current is too high)	16.7.1
	Zero current is unstable	16.7.2
	Sensor can be calibrated, but the current is less than about 350 nA/ppm at 25°C	16.7.3
	Process readings are erratic	16.7.4
	Readings drift	16.7.5
	Sensor does not respond to changes in monochloramine level	16.7.6

16.7.1 Zero current is too high

A.Is the sensor properly wired to the analyzer? See Section 3.3.

B.Is the zero solution monochloramine-free? Take a sample of the solution and test it for monochloramine level. The concentration should be less than 0.02 ppm.

C.Has adequate time been allowed for the sensor to reach a minimum stable residual current? It may take sev- eral hours, sometimes as long as overnight, for a new sensor to stabilize.

D.Check the membrane for damage and replace it if necessary. Be careful not to touch the membrane or cath- ode. Touching the cathode mesh may damage it.

16.7.2 Zero current is unstable

A.Is the sensor properly wired to the analyzer? See Section 3.3. Verify that all wiring connections are tight.

B.Readings are often erratic when a new or rebuilt sensor is first placed in service. Readings usually stabilize after about an hour.

C.Is the conductivity of the zero solution greater than 50 uS/cm? DO NOT USE DEIONIZED OR DISTILLED WATER TO ZERO THE SENSOR. The zero solution should contain at least 0.5 grams of sodium chloride per liter.

D.Is the space between the membrane and cathode mesh filled with electrolyte solution? Often the flow of elec- trolyte and be started by simply holding the sensor with the membrane end pointing down and sharply shak- ing the sensor a few times as though shaking down a clinical thermometer.

Verify that the sensor is filled with electrolyte solution. Refer to the sensor instruction manual for details.

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Contents Model 54eA Amperometric Hart Analyzer/ControllerEssential Instructions Page Model 54eA ANALYZER/CONTROLLER 10.0 11.012.0 13.0Section Title List of FiguresIii 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 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 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 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 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 pHGlass imp lo 20 MΩ Diagnostics OffAutocal Standard 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 Bar units mm Hg Bar meas AutoBarometric Pressure Lock program Lock config Noise rejection Main sensor calSecurity 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 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 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 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 current is too high Possible error warning during in-process calibrationZero reading Is unstable 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 Sensor does not respond to known pH changes Controller will not accept manual slope100 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 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