Pressure Systems 98RK-1 Span Calibration, Re-zero Calibration Summary, Description TCP/IP Data

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

4.2.2Re-zero Calibration Summary

The following is a simple, step-by-step procedure for executing a re-zero calibration of a Model 9816 Intelligent Pressure Scanner. Optional commands are shown within brackets [ ].

Description

TCP/IP Data

Disable automatic valve shifting after module power up.	[w0B01]
Insure that valves in RUN/CAL mode (default).	[w1200]
… normal data acquisition
Apply 0.0 psi differential to the appropriate CAL x and CAL
REF inputs on the back of the 98RK-1
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
Place calibration manifold back into the RUN position	[w0C00]
[if w0B01 command executed in step 1]
Store new offset coefficients into transducer nonvolatile	[w08]
memory
… continue normal data acquisition

4.3Span Calibration

For improved accuracy, NetScanner™ System 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 (for modules with firmware version 2.24 of higher). 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.

For Model 9816, 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 resulting new gain coefficients should always be

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