Omega Engineering OMB-CHARTSCAN 1400, Руководство пользователя

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Appendix A API Commands
ChartScan User’s Manual A-27
D#
- Set Relay Make Time
TYPE System
EXECUTION Deferred
SYNTAX
D#make
Specify how long to wait after closing a channel relay before reading valid
data, where
make
is the number of 520.833-microsecond intervals.
DESCRIPTION
The Set Relay Make Time (
D#
) command allows the user to increase the delay between closing a relay and
reading valid channel data. The system powerup default is:
make
=
6
= 3.125 milliseconds.
If common mode voltages on adjacent channels are widely dissimilar, reading inaccuracies can result. This
inaccuracy is due to inadequate settling time at the instrumentation amplifier when the unit is scanning between
channels. To eliminate these inaccuracies, the settling time can be increased using the
D#
command as shown
in the example below.
EXAMPLE
PRINT#1, “OUTPUT07;M#0X”
‘ Select Normal mode
PRINT#1, “OUTPUT07;W#32X”
‘ Select number of samples = 32
PRINT#1, “OUTPUT07;D#12X”
‘ Set Relay Make Time = 12 = 6.25 milliseconds
PRINT#1, “OUTPUT07;Y0,10,0X”
‘ Setup to read 10 past trigger scans
PRINT#1, “OUTPUT07;C1-360,1X
‘ Enable channels 1 - 360 for J type thermocouples
PRINT#1, “OUTPUT07;T1,8,0,0X”
‘ Arm the unit
PRINT#1, “OUTPUT07;@X”
‘ Trigger unit and collect scans