Druck ADTS 403F, Calibration Manual

Page: 29 / 40

Copyright 1996 Baker Hughes Company.
English–ADTS 403/405 Calibration Manual | 19
Automatic Calibration
5. Calibration using IEEE 488 SCPI
The IEEE 488 facility requires specialist knowledge of both IEEE 488 communications and
programming for specified, authorized calibration procedures. Only qualified personnel should
use this facility.
5.1 Automatic Calibration
Calibration using IEEE 488 SCPI follows the same procedure as manual calibration detailed in
Section 4 The SCPI commands required for automatic calibration are in the sub-set of the
CALibration: command. The Druck ADTS 403/405 SCPI Option User Manual, K0157 details each
command used in this procedure.
Figure 5 - 1: Automatic Calibration Arrangement
5.1.1 Offset, Slope and Curve Fit Adjustment
The SCPI command CALibration:ADJ causes the ADTS 403/405 to return the current values of
slope (span), offset (zero) and residual corrections (curve fit). The slope (span), offset (zero)
values can then, if necessary, be adjusted and sent back and stored by the ADTS 403/405. The
curve fit can be adjusted by modifying the 12 residual correction values. The whole process can
be automated with a computer program as described in the following.
5.1.2 Computer Algorithm for Offset, Slope and Curve Fit Adjustment
The calibration pressures used should ideally be the given values, shown in the following tables.
A permissible tolerance of ± 2 mbar can be entered providing the exact pressures are entered in
INFORMATION
Incorrect recalculation of residual error correction values
seriously affects the measurement accuracy of the ADTS. Only qualified
personnel must write calibration programs and the resulting calibration
accuracies must be verified before using the ADTS on equipment or aircraft
systems.
1 Personal computer 2 IEEE 488 connection
3 ADTS 405F 4 Pressure standard
1
2
4
3