Emerson 54e pH/ORP Temp coeff +.000, Sensor iso 07.00 pH, Solution Temperature Compensation

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MODEL 54e pH/ORP

SECTION 7.0

 

SPECIAL PROCEDURES AND FEATURES

7.3 SOLUTION TEMPERATURE COMPENSATION

Security Temperature Coeff Temperature sensor

ExitEnter

Temp coeff: +.000

Operate iso: +07.00 pH

Sensor iso: 07.00 pH

ExitEdit

This section is for advanced users only.

It explains how to input values for:

•the isopotential pH and

•the temperature coefficient for solution temperature compensation.

1.Beginning from the main menu, move the cursor down to "Program" and press Enter (F4). From the program menu, move the cursor down using the arrow key to highlight "Configure" and press Enter (F4).

Use the arrow key again to highlight "Temperature Coeff" (as shown on the left) and press Enter (F4) .

The Controller can compensate for two different temperature effects on the measured pH: the temperature effect on the pH sensor and the tem- perature effect on the actual pH of the process solution.

Sensor Temperature Compensation. The millivolt output of a pH sen- sor changes with temperature, which in turn, changes the measured pH value. The Sensor Isopotential pH (Sensor ISO) is the pH where the pH sensor's output does not change with temperature. The Controller uses the Sensor Isopotential pH value to correct for the temperature effect on the pH sensor. Except in rare instances (antimony or glass on metal elec- trode systems), the Sensor Isopotential pH is always 7.0 pH.

Solution Temperature Compensation. The actual pH of a solution can sometimes noticeably change with temperature. This can occur in solu- tions with a pH above 6.5 pH and in solutions containing weak acids, bases, and their salts. This effect can be compensated for by entering a Temperature Coefficient (Temperature Coeff) which is the change in solu- tion pH per degree centigrade (°C). If there is no noticeable solution pH change with temperature, or solution temperature compensation is not desired, the Temperature Coefficient (Temperature Coeff) should be set to 0.00.

Operating Isopotential pH. The Operating Isopotential pH (Operate ISO) is the Isopotential pH, which the Controller is using for overall tem- perature compensation. It represents a combination of both the sensor and the solution temperature compensations.

If no solution temperature compensation is being used (Temperature Coeff = 0), the Operating Isopotential pH (Operate ISO) is equal to the Sensor Isopotential pH (Sensor ISO).

If there is a non-zero Temperature Coefficient (Temperature Coeff) being used, the Controller automatically calculates the Operating Isopotential pH (Operate ISO) from the following relation:

Operate ISO = Sensor Iso - (Temperature Coeff) X (298.16)

Conversely, if an Operating Isopotential pH is known for a particular solu- tion, the Controller will automatically calculate the corresponding Temperature Coefficient.

Example: High Purity water with Ammonia, being measured with a normal pH sensor (Sensor Isopotential pH of 7.0 pH), has a Temperature Coefficient of -.033pH per °C and an Operating Isopotential pH of 16.84.

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Contents PH/ORP Hart Analyzer/Controller Model 54e pH/ORPEssential Instructions Electrical Shock HazardPage Section Title Description and SpecificationsModel 54E PH/ORP Microprocessor Analyzer Table No Title Appendix TitleList of Tables Table of Contents List of Figures About This DocumentDescription of Controls Section Description and SpecificationsGeneral Description Relative Humidity 95%, non condensing Alarms Specifications Physical Specifications GeneralPower Current OutputsAnalyzer Specifications @ 25C Recommended SensorsPart NO. Description Ordering InformationCode Options Locating the Controller Section InstallationMechanical Installation Unpacking and InspectionPanel Mounting Analog Output Wiring Section WiringPower Input Wiring Alarm Relay Output Wiring454EPH02 Tions will Result in Controller MALFUNC- Tion PH Sensor WiringPH Sensor Compatibility 454EPH01 Cable Dressing Final Electrical Check Wiring to Model Section Calibration IntroductionTemperature Calibration Hold Mode OffAdjust temp 25.1 C Automatic TWO-POINT Calibration Autocal bufferBuffer 1 -- Wait Calibration Notes Auto buffer cal doneUse the arrow keys to select the correct buffer 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/pHTrim Outputs Hold ModeOutput trim 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 mA Fault 22.00 mARange 4-20 mAl Hold feature setup Fault 22.00mAOutput 2 control Output 2 setup Hold Disable featureInterval timer AlarmsAlarm 3 control 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 SetupOn time 120 sec Timer DisableRecovery 600 sec Interval Timer Examples Zero offset 60 mV DiagnosticsDiagnostics Off Autocal Standard DiagnosticsAuto Calibration Setup Stabilize pH 0.01 pH Stabilize time 10 secAuto Calibration Setup Standard BuffersContinuous Sensor Diagnostics Section Theory of OperationSee .8 for instructions on chang- ing these setpoints Interval TimerTypical set points 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 ControlControl Loop Adjustment and Tuning Proportional Mode GainProportional Gain Plus Integral Reset Process Reaction Curve Method Process Reaction CurvePID Control Level 1 3 Password Privileges Section Special Procedures and FeaturesPassword Protection Custom Curve Configuring SecuritySecurity Lock allSensor iso 07.00 pH Solution Temperature CompensationTemp coeff +.000 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 TemperatureController preamp check Figure Preamplifier Troubleshooting ProcedurePreamp in a junction box 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
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