Pressure Systems 98RK Calibration Valve Control, Coefficients in transducer non-volatile memory

Pressure Systems, Inc. 98RK-1 & 9816 User’s Manual©

result should always be restored into the transducer’s non-volatile memory afterwards. In some cases, the user’s application may not require such a comprehensive adjustment as the other factory-determined pressure/temperature coefficients (stored permanently inside each transducer) are extremely stable. Only an occasional Re-zero adjustment may be all that is necessary.

When instructed to execute a particular sequence of sub-commands of the Configure Multi- Point Calibration ('C') command, the module will perform the various stages of the Multi-Point Calibration adjustment calibration function, and then update both the offset and gain coefficients in the module’s volatile (e.g., RAM) memory. The module will use this newly calculated data term for all subsequent engineering-unit calculations.

Note	When using the Configure/Control Multi-Point Calibration ('C')
	coefficients in transducer non-volatile memory.

4.4.1.Calibration Valve Control

Before executing a Multi-Point Calibration adjustment (using various forms of the Configure/Control Multi-Point Calibration (‘C’) command), Model 9816 modules should have their calibration valve placed in the proper position. For modules with only one common pressure range for its transducers, the CAL position should be used since the span calibration pressure can be applied between the CAL 1-8and CAL REF ports (see Section 4.3.1 for more information on these ports). Since the module will not attempt to shift this valve automatically, as it does for Re-zero adjustment, it should be placed in the desired position manually with the Set Operating Options ('w') command (option indexes = 0C and 12). This is illustrated in the example of the next section.

When multi-point calibrating Model 9816 modules with multiple ranges installed, the CAL port may be used to apply pressure to all transducers only if the specified proof pressure is not exceeded on any channel. If the application of a specific span pressure exceeds the proof pressure rating of any other transducer contained within the same scanner, the calibration pressures must be applied to the RUN side pneumatic input ports. Since the calibration command ('C') has a channel selection bit map parameter allowing it to calibrate only the desired pressure channels, the RUN port is a viable option for supplying the calibration pressures.

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