Emerson 54e pH/ORP instruction manual Standardize 7.01 pH, SINGLE-POINT pH Calibration

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MODEL 54e pH/ORP

SECTION 4.0

 

CALIBRATION

4.4 SINGLE-POINT pH CALIBRATION

Buffer calibration Standardize Adjust temperature

ExitEnter

A single-point calibration (standardization) should always be performed following a two-point calibration. It may have to be performed as often as once a day to ensure that the sensor is accurately reading pH. As the glass electrode or the porous reference plug fouls and ages, the pH read- ing will drift. The single-point calibration re-establishes the exact pH read- ing. Experience with your process and it's acceptable range of pH will dic- tate how often the single-point calibration will have to be performed. The procedure is most easily performed on-line by determining the pH of a process grab sample with a laboratory instrument. This value can then be entered into the Model 54e pH/ORP to make it agree with the lab instru- ment.

Many processes have effects on on-line sensors that cause them to read slightly different than grab samples measured with laboratory electrodes. Standardizing the controller allows both readings to agree. This proce- dure does not calculate the sensor slope.

1.Take a grab sample that is as close to the sensor as possible.

2.Using a calibrated pH instrument with automatic temperature com- pensation, determine the pH of the process or grab sample (as close to actual process temperature as possible). Continue with this pro- cedure if an adjustment is needed.

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

NOTE

The Hold Mode screen may appear if the feature was enabled in section 5.6. Changing the Hold Mode to ON holds the outputs in a fixed state, and avoids process upsets during calibration. Remember to change the Hold Mode back to OFF when calibra- tion is completed.

4.Move the cursor (using the down arrow key) from "Buffer Calibration" (or 2-pt calibration) to "Standardize" and press Enter (F4).

7.01pH

Standardize: 7.01 pH

ExitEnter

5.The pH reading in large numbers is the live process pH reading. The next line displays the pH reading when this screen was first accessed. Press Edit (F4) to perform the standardize.

Use the arrow keys to change the second line standardize value to the correct pH and press Save (F4) to complete the procedure. Esc (F3) will cancel.

The pH reading in the large display will change to the new value and the zero offset number will be recalculated.

4.01pH

Standardize: +07.00 pH

NOTE

Before exiting the calibration mode, remember to change the hold mode setting to OFF (if it was turned on in step 3).

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Contents Model 54e pH/ORP PH/ORP Hart Analyzer/ControllerElectrical Shock Hazard Essential InstructionsPage Model 54E PH/ORP Microprocessor Analyzer Description and SpecificationsSection Title List of Tables Appendix TitleTable No Title About This Document Table of Contents List of FiguresGeneral Description Section Description and SpecificationsDescription of Controls Power Specifications Physical Specifications GeneralRelative Humidity 95%, non condensing Alarms Current OutputsRecommended Sensors Analyzer Specifications @ 25CCode Options Ordering InformationPart NO. Description Mechanical Installation Section InstallationLocating the Controller Unpacking and InspectionPanel Mounting Power Input Wiring Section WiringAnalog Output 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 Introduction Section CalibrationAdjust 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 04.00pH 25C Calibrate pointPt calibration done Manual TWO-POINT CalibrationSINGLE-POINT pH Calibration Standardize 7.01 pHTemp comp Auto Temperature Compensation OptionsOutput trim 59.16 mV/pHOutput trim Hold ModeTrim Outputs PH Settings List Section Software ConfigurationRanges Factory Settings User Settings Diagnostics Section Outline of Menu Levels Changing Alarm Setpoints Alarm High 14.00pHSimulate tests Setpoint 07.00 pH4mA 0.00 pH 20mA 2.00 pH Setpoint 7.00 pHSetpoint + 06.90 pH Changing Output Setpoints PID onlyOutput OutputMA 0.00 pH 20 mA 14.00 pH Output 1 12.00 mA MA +00.00 pHTest output Test alarm Alarm setpoints Output setpointsTesting Outputs and Alarms Simulated testsTest alarm 1 Open Test alarm 1 OpenMeasure pH Display right AL2Security Caution Display contrast Timeout OnDisplay Control ModeChanging Output Parameters Output Control ParametersRange 4-20 mAl Fault 22.00 mARange 4-20 mA Output 2 control Output 2 setup Fault 22.00mAHold feature setup Hold Disable featureAlarm 3 control AlarmsInterval timer Setpoint 0.01 pH Delay 0 sec Alarm LowHysteresis 0.01 pH Delay 0 sec Relay Default NoneSetpoint +07.00 pH Relay default NoneTime period 30 sec URV 2.00 pHFeed limit Disable Alarm FaultTimeout 3600 sec Alarm 4 SetupRecovery 600 sec Timer DisableOn time 120 sec Interval Timer Examples Diagnostics Off DiagnosticsZero offset 60 mV Auto Calibration Setup DiagnosticsAutocal Standard Stabilize pH 0.01 pH Stabilize time 10 secStandard Buffers Auto Calibration SetupSection Theory of Operation Continuous Sensor DiagnosticsTypical set points Interval TimerSee .8 for instructions on chang- ing these setpoints Time Proportional Control TPC Mode Code Alarm RelaysAnalog Outputs Normal ModeController Mode Priority Chart Controller Mode PriorityCondition Definitions Action DefinitionsPID Control Code PID Control Mode CombinationsPID Control Measurement and Set Point Feedback ControlProportional Gain Plus Integral Reset Proportional Mode GainControl Loop Adjustment and Tuning Process Reaction Curve Process Reaction Curve MethodPID Control Password Protection Section Special Procedures and FeaturesLevel 1 3 Password Privileges Security Configuring SecurityCustom Curve Lock allTemp coeff +.000 Solution Temperature CompensationSensor iso 07.00 pH Operate iso +07.00 pH Troubleshooting is easy as 1, 2, 3… Section TroubleshootingDiagnostic Messages Description of problem Diagnostic MessagesSymptom Action Quick Troubleshooting GuideDiagnostic Variables Theoretical pH vs. Millivolt Values at 25C 77F Temperature Compensation Circuit Troubleshooting GuidelinesTroubleshooting Procedure Ohms Ambient TemperaturePreamp in a junction box Figure Preamplifier Troubleshooting ProcedureController preamp check Figure Junction Box Preamplifier Check No Power Troubleshooting GuideCoated glass electrode Clean with soft cloth and clean water Password protected Part Number Description Replacement PartsNON-WARRANTY Repair Warranty RepairSection Return of Material GeneralQuick Startup ORP Appendix a ORP ConfigurationItem Choices ORP Settings User Settings Table A-1. ORP Settings ListDiagnostics Section Choices ORP Settings User SettingsSimulated tests Output setpointsORP Calibration Standardize 400 mVSensor or Circuit Board only Return of Materials RequestReturn of Material WarrantySpecifications subject to change without notice
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