Measurement Specialties 9116 user manual Span Calibration, Re-zero Calibration Summary, Section

Pressure Systems, Inc. Model 9116 User’s Manual

4.2.2Re-zero Calibration Summary

Following is a simple, step-by-step procedure for executing a Re-zero calibration of a Model 9116 Intelligent Pressure Scanner. Optional commands are shown within brackets [ ].

Description	Model 9116 Command
Disable automatic valve shifting after module power up.	[w0B01]
Ensure valves in RUN/CAL mode (default)	[w1200]
… normal data acquisition
Apply 0.0 psi differential to the module CAL and CAL REF
inputs.
Place the module calibration manifolds into the CAL position	w0C01
[if w0B01 command executed in Step 1]
Delay for settling of pneumatic inputs
Verify that measured data reads near expected zero value	[rFFFF0]
Instruct module to calculate new offset coefficients for all 16	hFFFF
channels of Model 9116
Place calibration manifold back into the RUN position [if	[w0C00]
w0B01 command executed in Step 1]
Store new offset coefficients to transducer nonvolatile	[w08]
memory
… continue normal data acquisition

4.3Span Calibration

For improved accuracy, Model 9116 Intelligent Pressure Scanners are capable of independently performing a transducer calibration function, referred to as Span adjustment (or simply Span Cal). Actually, there is a provision to supply any suitable “upscale” pressure (e.g., actual transducer full-scale) during such a calibration adjustment. The Span adjustment calibration will result in a recalculated “gain” coefficient for each channel being calibrated, to compensate for any transducer or module gain errors. For best results, a Re-zero calibration should be performed before performing a span calibration. Also, note that a new and improved Multi-Point Calibration function exists. This function integrates the separate calibration functions (for Re-zero and Span adjustment described in Section 4.2 and this section) into a single function that adjusts both “offset” and “gain” coefficients at the same time, using two or more calibration points. Details of using this improved calibration function are described in

Section 4.4.

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