Omega Engineering OMB-NETSCAN, User Manual

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API Command Reference Appendix A
A-32 NetScan User’s Manual
L - Set Trigger Level
TYPE Channel
EXECUTION
Deferred
SYNTAX Lchan,
level,
hyst
Sets the level against which the testing of channel readings should be
performed where chan is the channel number such that 1 < chan < max ,
where max = 128 for NetScan.
level
is the level against which the readings are tested to determine if the
level has been exceeded.
hyst is the hysteresis level.
L? Query the the current level settings
DESCRIPTION
The Set Trigger Level (
L
) command simply sets the level against which the testing of channel readings should be
performed. The Set Trigger Configuration ( T ) command should be used to configure whether the level condition
should be tested for going above the specified level or below the specified level.
Note: This command is only valid for trigger start/stop events of T4 and T5 .
The parameter level is the value, which, if exceeded (by going above or below it as defined), should generate
a trigger event. The parameter
hyst
is the hysteresis value that, with
level
, is used to test whether the level
condition still persists. The level condition will persist until the channel readings no longer exceed the level as
specified. Further, in order to come out of the level condition, the channel readings must not exceed the
aggregate of the level and hysteresis values. The format for the
level and hyst arguments follow the rules
for readings input defined under the Set Data Format ( F ) Command and in the Data Format section of
Appendix D.
EXAMPLE
PRINT#1, “F0,0X” ‘ Set the engineering units format to be degrees C
PRINT#1, “L1,100.0,10.0X”
‘ Set the level channel to be channel 1 at a level 100.0
°
C with a hysteresis of 10.0
°
C
PRINT#1, “L?X” ‘ Read the current level setting
LINE INPUT#1, L$
PRINT L$ ‘ The screen shows L001,+0100.0,+0010.0
PRINT#1, “T4,5,0,0X” ‘ Set the unit to start on channel going above the level
and to stop on the channel going below the level