Emerson PN 51-FCL-1056 instruction manual Calibration Error during Standardization

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MODEL FCL-1056

SECTION 9.0

 

TROUBLESHOOTING

9.6.2 Calibration Error during Standardization.

During standardization, the millivolt signal from the pH cell is increased or decreased until the pH agrees with the pH reading from a referee instrument. A unit change in pH requires an offset of about 59 mV. The analyzer limits the offset to ±60 mV. If the standardization causes an offset greater than ±60 mV, the analyzer will display the Offset Error screen. The standardization will not be updated. Check the following:

1.Is the referee pH meter working and properly calibrated? Check the response of the referee sensor in buffers.

2.Is the sensor fully immersed in the process liquid? If the sensor is not completely submerged, it may be measuring the pH of the liquid film covering the glass bulb and reference element. The pH of this film may be different from the pH of the bulk liquid.

3.Is the sensor fouled? The sensor measures the pH of the liquid adjacent to the glass bulb. If the sensor is heavily fouled, the pH of liquid trapped against the bulb may be different from the bulk liquid.

4.Has the sensor been exposed to poisoning agents (sulfides or cyanides) or has it been exposed to extreme temperature? Poisoning agents and high temperature can shift the reference voltage many hundred millivolts.

9.6.3 Sensor Does Not Respond to Known pH Changes.

1.Is the pH sensor responsive to buffers? Check sensor response in two buffers at least two pH units apart.

2.Did the expected pH change really occur? Use a second pH meter to verify the change.

3.Is sample flowing past the sensor? Be sure the liquid level in the constant head sampler is level with the central overflow tube and that excess sample is flowing down the tube. If necessary, disassemble and clean the over flow sampler. See Section 8.4.

4.Is the sensor properly wired to the analyzer? See Section 3.2.

5.Is the glass bulb cracked or broken? Check the glass electrode impedance. See Section 9.6.1.

6.Is the analyzer working properly? Check the analyzer by simulating the pH input. See Section 9.9.

9.6.4 Buffer Calibration Is Acceptable, Process pH Is Slightly Different from Expected Value.

Differences between pH readings made with an on-line instrument and a laboratory or portable instrument are normal. The on-line instrument is subject to process variables, for example ground potentials, stray voltages, and orientation effects that may not affect the laboratory or portable instrument. To make the process reading agree with a referee instrument, see Section 6.4.5.

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Contents FCL with 1056 Analyzer Essential Instructions Ppm mg/L EnglishFree Chlorine ORPS1 Free Cl PH Correction Manual Live/ContinousS1 Manual pH Temp Units Menu Tree Calibrate Sensor 1 Free chlorineSensor 2 pH Diagnostic Setup AlarmsTemperature Reset AnalyzerAbout This Document Rev. Level DateTable of Contents FCL-1056Table of Contents CONT’D List of TablesList of Tables CONT’D IiiSection Description and Specifications FeaturesApplications Specifications General Specifications SensorSpecifications Analyzer Component Parts AccessoriesOrdering Information PH Correction required selectionThis page left blank intentionally FCL-01 free chlorine without continuous pH correction Section InstallationUnpacking and Inspection FCL-02 free chlorine with continuous pH correctionGeneral Information InstallationInstalling the Sensors Mounting, Inlet, and Drain ConnectionsModel FCL-01 This page left blank intentionally Power Section WiringPOWER, ALARM, and Output Wiring Analog output wiringSensor Wiring Alarm relay connectionsWiring Diagram for Free Chlorine Sensor Model FCL-1056 Section Wiring Section Display and Operation DisplayKeypad Outputs Programming the ANALYZER-TUTORIALCalibrate RangeO2 S1 4mA 0.0C O2 S1 20mA 100.0C Output Range O1 S1 4mA 0.000 ppmO1 S1 20mA 08.50 ppm SecurityUsing Hold HoldLanguage English Contrast Configuring the Main DisplayMain Format Format, Language, Warning, and ContrastDefault Settings Section Programming the AnalyzerGeneral Alarms Sensor assignmentChoices Default CONFIGURING, RANGING, and Simulating Outputs DefinitionsConfigure ProgramOutputAssign Output Output Range Configure Simulate Output ConfigureProcedure Ranging Outputs O1 S1 20mA 10.00 ppm O2 S1 4mA 0.0C O2 S1 20mA 100.0CRangeSimulate Configure SimulateConfiguring Alarms and Assigning Setpoints OutputSection Programming the Analyzer Alarms Configure/SetpointAlarm Simulate Alarms Configure/SetpointAlarm Simulate Alarm Don’t SimulateAlarms Configure/Setpoint Simulate Synch Timers YesProcedure Synchronizing Timers Configuring the Measurement Definitions ChlorineDefinitions pH/ORP Measurement Sensor1SensorConfiguring Temperature Related Settings Definitions pHConfiguring Security Settings Program Outputs Alarms MeasurementTemperature S1 Temp Comp Auto S2 Temp CompSecurity Program Alarms Measurement TemperatureSetting UP Diagnostics SecurityGI Fault High 1500MΩ Program Measurement Temperature SecurityDiagnostic Setup Procedure Setting Up DiagnosticsReset Analyzer Resetting the AnalyzerProgram Temperature Security Diagnostics Reset AnalyzerCalibrating Temperature Section CalibrationIntroduction S1 Calibration ProcedureCalibrate SensorSensor11 Output S1 Calibration + 25.0CProcedure-Zeroing the Sensor Calibration Free ChlorineCalibrate SensorSensor11 Output S1 Calibration Choose Free ChlorineSensor Temperature S1 Calibration ZeroZeroCalCal Process CalCalibrate? Sensor OutputCalibration pH Calibration Slope and OffsetZeroBufferCalCal Auto07.01 pH 10.01 pHStable Time Manual BufferManual Buffer 1 0 7.00 pH S2 pH Manual Cal Buffer Slope 56.19 mV/pH Offset Redox Temperature S2 pH Cal Buffer CalStandardizeStandardize S1 Enter Value 00 pHProcedure-Entering a Known Slope and Offset Calibration Analog Outputs OutputMA Output Cal Meter 000 mA Trim Complete This page left blank intentionally Section Digital Communications Model FCL-1056 Section Section Maintenance AnalyzerChlorine Sensor Cleaning the membraneReplacing the electrolyte solution and membrane GeneralCleaning the Sensor Other MaintenancePH Sensor Cleaning the flow controller Constant Head Flow ControllerWeight Weight Faults Section TroubleshootingUsing the Diagnostic Feature OverviewTroubleshooting When a Fault Message is Showing Fault message Explanation SectionHardware Error Sensor Incompatible Sensor CPU ErrorSensor ADC Error Sensor RTD OpenReference Impedance Too High Sensor RTD Out of RangeGlass Z Too High Broken GlassTroubleshooting When a Warning Message is Showing Troubleshooting When no Error Message is Showing Chlorine Sensor can be calibrated, but the current is too low Process readings are erraticReadings drift Sensor does not respond to changes in chlorine level Chlorine readings are too lowTroubleshooting When no Error Message is Showing pH Calibration Error During Two-Point CalibrationCalibration Error during Standardization Sensor Does Not Respond to Known pH ChangesPH Readings Are Moderately Noisy and Tend to Wander Anod Troubleshooting When no Error Message is Showing GeneralSimulating Inputs Chlorine CathSimulating Inputs pH Simulating pH inputSimulating Inputs Temperature Simulating temperaturePage Europe Americas HeadquartersASIA-PACIFIC GermanyWarranty Specifications subject to change without notice
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