Emerson 51-DO-04, 51-DO-03 instruction manual Sensor must be in zero solution, Zeroing the Sensor

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MODEL DO-03/04	SECTION 7.0
	CALIBRATION - DISSOLVED OXYGEN

7.2ZEROING THE SENSOR

1.Place the sensor in a fresh solution of 5% sodium sulfite (Na2SO3) in water. Be sure air bubbles are not trapped against the membrane. The current will drop rapidly at first and then gradually reach a stable zero

value. To monitor the sensor current, go to the main display. Press any key to obtain the main menu. Press

the key once to highlight “Diagnostic variables.” Press Enter (F4). The sensor current is the second item in the display. Note the units: nA is nanoamps, μA is microamps. To return to the main display, press exit (F1) twice. Typical zero current for a 499ADO sensor is less than 50 nA.

A new sensor or a sensor in which the electrolyte solution has been replaced may require several hours (occa- sionally as long as overnight) to reach a minimum current. DO NOT START THE ZERO ROUTINE UNTIL THE SENSOR HAS BEEN IN ZERO SOLUTION FOR AT LEAST TWO HOURS.

Calibrate main sensor Zero main sensor Adjust temperature

ExitEnter

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

NOTE

If Hold was enabled in Section 5.5, the hold screen will appear. To activate hold, refer to Section 5.5, step 9.

3.Press the key once to move the cursor to “Zero main sensor.” Press Enter (F4).

0.0 ppm

Sensor must be in zero solution

Abort Cont

4.The screen at left appears. Press Cont (F3). “Wait” flashes until the sensor is stabilized. Once the zero step is complete, the message “Sensor zero done” appears.

5.Press Exit (F1) three times to return to the main display.

NOTE

If Hold was activated during calibration, “Hold Mode Activated” will continue to flash in the main display. Return the sensor to normal and deactivate Hold. Refer to Section 5.5, step 9.

NOTE

During calibration, ERROR and WARNING messages may appear. If an ERROR message appears, press Exit (F1) to leave and return to the previous screen. If a WARNING message appears, press Cont (F3) to continue the calibration or press Abort (F1) to leave. Continuing the calibration after a warning message appears may cause substantial errors in the subsequent measurement. Refer to Section 15.4 for assis- tance.

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Contents Dissolved Oxygen Measurement System with Air Blast Cleaner Model DO-03/04Essential Instructions Page Model DO-03/04 Measuring System Section Title11.0 List of Tables10.0 Iii List of FiguresSection Title Section Specifications Features and BenefitsRFI/EMI EN-61326 PowerRepeatability ±0.05 ppm 25C Output Accuracy ± 0.05 mAMaterials of Construction Maximum continuous pressure 50 psig 446 kPa absMaximum distance between compressor and sensor Analyzer dimensions Enclosure dimensions 9240048-00 Tag, stainless steel, specify marking Power required selectionDescription Unpacking and Inspection Section InstallationInstallation Model or part number DescriptionAssembling the pipe and pipe clamp Installing the air compressor enclosureInstalling the handrail mounting assembly Assembling the washer head and pipe boom Installing the sensor in the washer head assemblyAttaching the pipe boom to the handrail mounting assembly Attaching the air compressor enclosure to the handrail Installing the sensor in the washer head assembly General Section WiringPOWER, ALARM, and Output Wiring 454EPH02 Section Section General Sensor WiringWiring the Oxygen Sensor Display Alarm StatusSection Display and Operation KEY Functions and ControlSection Software Configuration Menu Tree for the 54eA AnalyzerOn following Main Menu Calibrate See Diagnostic Variable see Program Settings List Choices Factory Settings SetpointsChoices Factory Settings Configure Choices Factory Settings Alarm 2 setpoint Alarm setpointsAlarm 1 setpoint Alarm 3 setpointMA 0.00 ppm 20 mA 20.00 ppm Output 1 12.00 mA Ranging the OutputsTest output Test alarm 1 OpenSimulated tests Measure Oxygen Outputs AlarmsDisplay Meas units ppmLanguage English Display left Display right Out Display contrast Timeout OnTemp units C Output 1 mA Output 2 mA Output Measurement OutputsOutput 1 control Range 4-20 mA Dampen 0 sec Hold Last Value Output 1 SetupOutput 1 Control Alarm 1 setup Alarm 2 control ConfigureAlarm 1 control Changing Alarm ParametersAlarm Low Alarm 1 controlAlarm 1 setup Activate ProcessTimeout 3600 sec Alarm FaultFeed limit Disable Alarm 4 setupTimer Disable Timer Time activated Interval 24.0 hr Alarm 4 setup Feed limit timerInterval timer Interval timer setupTemp units C Temperature Compensation and Temperature UnitsTemp comp Auto Temp comp Manual Temp units C60 Hz Noise ReductionBarometric Pressure Bar meas AutoBar units mm Hg Main sensor cal Salinity 0.0 o/ooNoise rejection Main sensor cal Security SecurityAction Definitions Analyzer Mode PriorityCondition Definitions Section Calibration Temperature IntroductionAdjust temp + 025.1 C Temperature CalibrationSection Calibration Dissolved Oxygen Sensor Current as a Function 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 InstrumentStandardize Zero main sensor Adjust temperatureCalibrate main sensor Calibrating Barometric PressureSection Calibration Current Outputs Trimming the OutputsCleaning the membrane Section MaintenanceReplacement Parts Replacing electrolyte solution and membraneSection Power Fuse Spare PartsReplacement Parts Location Part Number Description AIR Blast Sensor WasherFault message Explanation See Section Section TroubleshootingTroubleshooting When a Fault Message is Showing OverviewCheck sensor zero Temperature error low or highHigh input current Sense line openZero current is too high Troubleshooting When no Fault Message is Showing OxygenProblem See Section Barometric pressure reading is too high or too low Possible error warning during in-process calibrationZero reading Is unstable Sensor does not respond to changes in oxygen level Process readings are erraticReadings drift Oxygen readings are too lowSimulating Inputs Dissolved Oxygen Troubleshooting not Related to Measurement ProblemsProblem Action Sensor Polarizing Voltage Resistance Expected currentSimulating Temperature Simulating temperatureSection Return of Material GeneralReturn of Materials Request Sensor or Circuit Board onlyWarranty Specifications subject to change without notice