Omega Engineering OMB-CHARTSCAN 1400, User Manual

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API Commands Appendix A
A-34 ChartScan User’s Manual
G
- Calibrate Channel Gain
TYPE Calibration
EXECUTION Immediate
SYNTAX
Gchan,
type
Calibrate the correction gain constants for given option card where
chan
is
the channel number such that
1
<
chan
<
max
,
where max = 128 for ChartScan/1400. The chassis is
chan = 0
.
type
is the channel type.
DESCRIPTION
Note: This command is only for advanced users who perform their own calibration. It is not necessary for
normal, everyday operation.
Active only in calibration mode, the Calibrate Channel Gain (
G
) command is used to calibrate the correction gain
constants for a given slide-in card. The channel gain value is necessary in order for the internal firmware to
accurately interpret readings coming from the input channels. This command will take the parameters
chan
and
type
and will calculate the gain based on the present channel input voltage.
Note: To achieve correct results, this command must be issued twice. First with a negative input voltage and
then with a positive input voltage.
Each time the command has been issued, the precision voltage source must remain at its value until the trigger
LED stops flashing. For further details on channel calibration, see Chapter 6.
EXAMPLE
PRINT#1, “OUTPUT07;K12345X”
‘ Enter Calibration Mode
‘ Apply negative precision voltage
PRINT#1, “OUTPUT07;G17,1"
‘ Calculate (-) gain for T/C card, card #2
‘ Wait for command to complete
‘ Apply positive precision voltage
PRINT#1, “OUTPUT07;G17,1"
‘ Calculate (+) gain for T/C card, card #2
‘ Wait for command to complete
‘ Remove precision voltage
PRINT#1, “OUTPUT07;EX”
‘ End Calibration Mode