Emerson 54e pH/ORP Preamplifier Troubleshooting Procedure, Preamp in a junction box Figure

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MODEL 54e pH/ORP

PREAMPLIFIER TROUBLESHOOTING PROCEDURE

Use this procedure when diagnosing the circuit which carries the signal from the sensor. There are 3 sepa- rate procedures, depending on where the preamplifi- er is located.

A. Preamp in a junction box (Figure 8-2)

1.Verify that the controller's preamp switch is in the sensor/J box position (see Figure 2-5).

2.Remove the cover of the junction box.

3.Disconnect the BNC adapter or remove leads from TB1-7 and TB1-10 (whichever is connect- ed).

4.Install a jumper between 7 and 10, 3 and 4, and 7 and 8 (see Figure 8-2).

5.The controller should now read approximately 7 pH.

NOTE

If the controller has been calibrated with a large zero offset, the pH may not be close to 7. In this case, standardize the con- troller at 7. (Section 3.4).

6.If the controller does not read correctly (after standardizing, if necessary), go to step B.

SECTION 8.0

TROUBLESHOOTING

B. Controller preamp check (Figure 8-3)

1.Disconnect all sensor wiring from the controller at TB2.

2.Verify that the preamp location switch is in the analyzer position, and that temperature compen- sation is set to manual at 25°C or 77°F (see Section 3.5).

3.Jumper TB2-3 to TB2-4 and TB2-7 to TB2-8.

4.Jumper TB2-7 to TB2-10 to simulate 7 pH.

5.The controller should now read 7 pH (or 0 mV in ORP mode).

NOTE

If the controller has been calibrated with a large zero offset, the pH may not be close to 7. In this case, standardize the con- troller at 7. (Section 3.4).

6.If the controller does not read correctly (after standardizing, if necessary), replace the con- troller.

7.If a millivolt source is available, it can be con- nected to TB2-7 and TB2-10 to simulate pH val- ues. Refer to Figure 8-1 for the relationship between mV and pH, sample values are +172 mV for 4 pH and -172 mV for 10 pH.

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Contents PH/ORP Hart Analyzer/Controller Model 54e pH/ORPEssential Instructions Electrical Shock HazardPage Model 54E PH/ORP Microprocessor Analyzer Description and SpecificationsSection Title List of Tables Appendix TitleTable No Title Table of Contents List of Figures About This DocumentGeneral Description Section Description and SpecificationsDescription of Controls Relative Humidity 95%, non condensing Alarms Specifications Physical Specifications GeneralPower Current OutputsAnalyzer Specifications @ 25C Recommended SensorsCode Options Ordering InformationPart NO. Description Locating the Controller Section InstallationMechanical Installation Unpacking and InspectionPanel Mounting Analog Output Wiring Section WiringPower Input Wiring Alarm Relay Output Wiring454EPH02 PH Sensor Compatibility PH Sensor WiringTions will Result in Controller MALFUNC- Tion 454EPH01 Cable Dressing Final Electrical Check Wiring to Model Section Calibration IntroductionAdjust temp 25.1 C Hold Mode OffTemperature Calibration Buffer 1 -- Wait Autocal bufferAutomatic TWO-POINT Calibration Use the arrow keys to select the correct buffer Auto buffer cal doneCalibration Notes Pt calibration done Calibrate pointPt 04.00pH 25C Manual TWO-POINT CalibrationStandardize 7.01 pH SINGLE-POINT pH CalibrationOutput trim Temperature Compensation OptionsTemp comp Auto 59.16 mV/pHOutput trim Hold ModeTrim Outputs Section Software Configuration PH Settings ListRanges Factory Settings User Settings Diagnostics Section Outline of Menu Levels Simulate tests Alarm High 14.00pHChanging Alarm Setpoints Setpoint 07.00 pHSetpoint + 06.90 pH Setpoint 7.00 pH4mA 0.00 pH 20mA 2.00 pH Changing Output Setpoints PID onlyMA 0.00 pH 20 mA 14.00 pH Output 1 12.00 mA OutputOutput MA +00.00 pHTesting Outputs and Alarms Alarm setpoints Output setpointsTest output Test alarm Simulated testsTest alarm 1 Open Test alarm 1 OpenDisplay right AL2 Measure pHDisplay contrast Timeout On Security CautionChanging Output Parameters Control ModeDisplay Output Control ParametersRange 4-20 mAl Fault 22.00 mARange 4-20 mA Hold feature setup Fault 22.00mAOutput 2 control Output 2 setup Hold Disable featureAlarm 3 control AlarmsInterval timer Hysteresis 0.01 pH Delay 0 sec Alarm LowSetpoint 0.01 pH Delay 0 sec Relay Default NoneTime period 30 sec Relay default NoneSetpoint +07.00 pH URV 2.00 pHTimeout 3600 sec Alarm FaultFeed limit Disable Alarm 4 SetupRecovery 600 sec Timer DisableOn time 120 sec Interval Timer Examples Diagnostics Off DiagnosticsZero offset 60 mV Autocal Standard DiagnosticsAuto Calibration Setup Stabilize pH 0.01 pH Stabilize time 10 secAuto Calibration Setup Standard BuffersContinuous Sensor Diagnostics Section Theory of OperationTypical set points Interval TimerSee .8 for instructions on chang- ing these setpoints Alarm Relays Time Proportional Control TPC Mode CodeNormal Mode Analog OutputsCondition Definitions Controller Mode PriorityController Mode Priority Chart Action DefinitionsPID Control PID Control Mode CombinationsPID Control Code Measurement and Set Point Feedback ControlProportional Gain Plus Integral Reset Proportional Mode GainControl Loop Adjustment and Tuning Process Reaction Curve Method Process Reaction CurvePID Control Password Protection Section Special Procedures and FeaturesLevel 1 3 Password Privileges Custom Curve Configuring SecuritySecurity Lock allTemp coeff +.000 Solution Temperature CompensationSensor iso 07.00 pH Operate iso +07.00 pH Section Troubleshooting Troubleshooting is easy as 1, 2, 3…Diagnostic Messages Diagnostic Messages Description of problemQuick Troubleshooting Guide Symptom ActionDiagnostic Variables Theoretical pH vs. Millivolt Values at 25C 77F Troubleshooting Procedure Troubleshooting GuidelinesTemperature Compensation Circuit Ohms Ambient TemperaturePreamp in a junction box Figure Preamplifier Troubleshooting ProcedureController preamp check Figure Junction Box Preamplifier Check Troubleshooting Guide No PowerCoated glass electrode Clean with soft cloth and clean water Password protected Replacement Parts Part Number DescriptionSection Return of Material Warranty RepairNON-WARRANTY Repair GeneralAppendix a ORP Configuration Quick Startup ORPTable A-1. ORP Settings List Item Choices ORP Settings User SettingsChoices ORP Settings User Settings Diagnostics SectionOutput setpoints Simulated testsStandardize 400 mV ORP CalibrationReturn of Materials Request Sensor or Circuit Board onlyWarranty Return of MaterialSpecifications subject to change without notice