Measurement Specialties 9116 User Manual

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Pressure Systems, Inc.                                                                                        Model 9116 User’s Manual 
 
 
 
Page 95 
 
www.PressureSystems.com 
For Model 9116, with integral DH200 transducers, internal manifolds and valves allow a Span 
adjustment pneumatic calibration to be accomplished easily and automatically.  
 
It is recommended that a Span adjustment be performed whenever new transducers are 
installed in the instrument.  In such cases, the new gain coefficients that result should always be 
stored back into the transducer’s non-volatile memory.  In other cases, the user’s application 
may not require periodic span adjustment since 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 Calculate and Set Gains (‘Z’) command, the module will perform 
the Span adjustment calibration, and then update the gain coefficients in its memory.  It will 
subsequently use the newly calculated gain terms for subsequent engineering-unit calculations 
until power is lost to the module. 
 
 
Note
 
When using the Calculate and Set Gain (‘Z’) command, only the local 
variables in the module’s volatile main memory (RAM) are changed.
 
 
4.3.1. 
  Span 
Calibration 
Valve 
Control 
 
Before executing a Span adjustment (Calculate and Set Gains (‘Z’) command), the Model 
9116
 modules should have their calibration manifold valve placed in the proper position.  For 
single pressure range units the CAL position should be used since the span calibration pressure 
can be applied between the CAL and CAL REF ports.  Since the module will not attempt to shift 
this valve automatically, as it does for Re-zero adjustment, it should manually be placed in the 
desired position with the Set Operating Options (‘w’) command (option indexes = 0C and 12). 
 
When span calibrating Model 9116 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
.  Refer to Calculate and Set Gains (‘Z’) command to specify the 
channels to be affected by the command in a multi-range unit.  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 (‘Z’) 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.