Teledyne 7300A manual CAL-OUT Function

Page 50

4 Operation

Model 7300A

 

 

 

 

 

 

 

 

 

How the offset value is selected:

To find out what the offset value should be, the intended zero calibration gas and the mix of the process background gas must be procured. This of course assumes that the zero gas and the process background gas are very different and that an offset will occur.

1.Let the intended zero calibration gas flow through the 7300A sample cell (this assumes that you have started up your system as recommended by the manual or technical personnel) and do a zero on the instrument. Leave the offset set to zero value.

2.At the end of the zero function, make sure the analyzer reads zero.

3.Span the analyzer

4.Flow the process background gas mix through the 7300A sample cell on the Analyze mode. Wait for the reading to become stable. Write the reading down. Change the sign of the reading: This is the offset to be entered.

5.Do a manual run to check the analyzer operation. Reintroduce the zero calibration gas. Enter the zero Offset value as explained above.

6.Check that the instrument reads the entered offset.

7.Reintroduce the process background gas mix to the 7300A sample cell in the Analyze mode. It should read close to zero once the reading is stable (+/- 1% error of full scale).

Spanning the 7300A:

Since the instrument might be spanned with a background gas the same as the zero calibration gas, the span value to be entered should be the span concentration plus the offset value (if the offset value has a minus sign then algebraically it becomes a subtraction).

4.3.11CAL-OUT Function

Selecting the CAL-OUT function in menu makes possible to calibrate the output of the 4 to 20 madc. In hardware terms, this function calibrates the Digital to Analog converter that feeds a signal to the 4 to 20 madc E/I converter. Calibrating the 4 to 20 madc output should be part of routine maintenance.

To calibrate the 4 to 20 madc output, a calibrated multi-meter configured as an ammeter has to be connected to the analyzer to monitor the output. When ready, enter the CAL-OUT function. The following screen will be shown on the VFDdisplay:

4-14

Teledyne Analytical Instruments

Image 50
Contents Model 7300A Teledyne Analytical InstrumentsModel 7300A Copyright 2000 Teledyne Analytical InstrumentsInfrared Gas Analyzer Technician Record Sheet Application Impurity of InterestModel 7300A Teledyne Analytical Instruments Model 7300A Model 7300A Infrared Gas Analyzer Table of Contents IntroductionInstallation Operation Electrical/Control Unit Modes/Functioning Table of ContentsStart-up and Theory of Operation Maintenance AppendixInfrared Gas Analyzer Introduction OverviewTypical Gas Applications Introduction Model 7300A Main Features of the AnalyzerGeneral Ndir Analyzer Introduction Model 7300A Teledyne Analytical Instruments Unpacking the Analyzer/Inspection Installing and Connecting the AnalyzerInfrared Gas Analyzer Installation User Connections Installation Model 7300AElectrical Power Connections Calibration GasesSample Delivery System Infrared Gas Analyzer Installation Pipe ConnectionsElectrical Connections Rear Panel Venting the System3 50-Pin Equipment Interface Connector Installation Model 7300A Primary Input PowerFuse Installation Analog OutputsOutput V dc Output mA dc Pin FunctionExamples Alarm Relays Range Voltage Current mA ApplicationPin Contact Digital Remote Cal InputsRemote Calibration Connections Network I/O Remote Valve ConnectorRange ID Relays 4 RS-232 Port FET Series ResistanceGas Requirements Command DescriptionParameter Setting Calibration Testing the SystemCalibration Calibration Fluids Infrared Gas Analyzer Installation Installation Model 7300A Teledyne Analytical Instruments Initial Set-up and Zeroing PreliminaryNdir Analyzer Startup Infrared Gas Analyzer Start-up and OperationOperational Calibration Start-up and Theory of Operation Model 7300ATheory of operation General AnalyzerBlock Diagram of the Model 7300A Electronics Circuit Description Digital Signal Processing & Electronics Linearizer Linearizer Output Linearizer Input Teledyne Analytical Instruments Page Introduction Infrared Gas Analyzer OperationOperation Model 7300A Using the ControlsAnalysis Mode Mode/Function SelectionSetup Mode Setup Mode Escape Data EntryEnter Setting up an AUTO-CAL EnterInfrared Gas Analyzer Operation Password Protection Entering the PasswordInstalling or Changing the Password AAASystem Self-Diagnostic Test Logging OutModel Screen Checking Linearity with AlgorithmTroubleshooting information Digital Filter Setup Zero Offset Adjustment CAL-OUT Function Adjst output to 4ma ENT to OK Zero and Span Functions Zero CalAuto Mode Zeroing Manual Mode Zeroing Cell FailureAuto Mode Spanning Span CalManual Mode Spanning Alarms Function InstallationPress enter again to set the alarm setpoints Range Select Function Manual Select/Define Range ScreenAuto Screen Precautions Analyze Function Illustrates these schemes graphicallyProgramming Set Application ScreenOFFST/INVRT ENT Curve Algorithm Screen Checking the linearizationManual Mode Linearization Auto Mode Linearization Special Function Setup Offset OUTPUT/Reversal Output Output Signal ReversalOutput Signal Offset Polarity ReversalGain Preset Maintenance Infrared Gas Analyzer MaintenanceFilter Routine MaintenanceMaintenance Model 7300A System Self Diagnostic Test Ndir Analyzer Measurement CellAnalog PowerMajor Internal Components PreampCell Assembly Troubleshooting General Trouble Shooting Chart Maintenance Model 7300A Infrared Gas Analyzer Maintenance Maintenance Model 7300A Teledyne Analytical Instruments Infrared Gas Analyzer Appendix Appendix Model 7300A SpecificationsDrawing List Recommended 2-Year Spare Parts List Qty DescriptionAttachment 7300A Infrared Gas Analyzer Appendix