Measurement Specialties 9116 - Manual (Page 109)

Pressure Systems, Inc. Model 9116 User’s Manual
Page 100 www.PressureSystems.com
Verify that pressure reads correctly. [rFFFF0]
When the data are stable, enter another Collect Data
(‘01’) sub-command of ‘C’ specifying this second
calibration point (2) with 5.0 psi pressure. C 01 2 5.0
Apply 3rd calibration pressure to the module’s CAL or
RUN inputs. A mid-scale negative (-2.5 psi) point is
assumed in this case. A vacuum pump is normally
required to achieve such a pressure with 903x calibrators.
Verify that measured pressure reads correctly. [rFFFF0]
When the data are stable, enter last Collect Data (‘01’)
sub-command of ‘C’ for this point (3) with a negative
(-2.5 psi) pressure. C 01 3 -2.5
Now that data have been collected for every point
originally specified, calculate and apply the new coefficient
data with a Calculate and Apply (‘02’) sub-command of
‘C’. This also restores the module to using its original
averaging parameters that existed before the first ‘C’
command. C 02
Place calibration manifold back into the RUN position, if
the CAL position was used. [w0C00]
Store new offset and gain coefficients into transducer non-
volatile memory. w08
w09
… continue normal data acquisition.
4.5 Coefficient Storage
The various calibration functions described in Sections 4.2 through 4.4 update the active offset
and gain coefficients, respectively, in the module’s volatile main memory (RAM) only. These
newer calibration coefficients will be lost when instrument power is turned off. The Set/Do
Operating Options (‘w’) command may be used to also store these coefficients back in each
transducer’s nonvolatile memory. This command’s option index = 08 will store new offset
coefficients, while its option index = 09 will store new gain coefficients.
A user may read (and should verify) any new offset and/or gain coefficients after performing
each calibration adjustment command (i.e., by saving coefficient data returned in a command
‘h’ or ‘Z’ response), or the Read Internal Coefficients (‘u’) command may be used to read
them any time after calibration adjustment commands have been performed (see coefficient
indexes cc=00 and 01 for arrays aa=01 through 10). These “adjusted” coefficients may be
verified, and then saved by storing them in each transducer’s non-volatile memory with the ‘w’
command described above.