Operation Techniques 93
Example 4-3 Sample Of Using Pulse Trigger
Trigger conditions
Conjunction Trigger parameter Condi-
tion
Operate
limit
Release
limit
Condition #1 OR Pulse input #1 ON
Condition #2 AND Relay #1 status OFF
Setpoint actions Delays
Action type Action target Unit Operate Release
Action #1 Operate relay #1 1 s 0 1
Notice that the pulse trigger is ANDed with the reversed relay status to guarantee
that the setpoint will be released after a 1-second operation, with no regard to the
time that new pulse comes. Obviously, pulses following in intervals less than 1
second will be considered as one pulse.
Repeated Setpoint Operations using Time Trigger
Suppose, we are intending to provide reset of extreme demands on the first day of
each month synchronously with an external time reference pulse denoting beginning
of the new demand interval. The demand interval duration is assumed to be 15
minute.
Before reset will be made, the instrument should provide self-readings of all
maximum demands that were logged during the month, and store them in data
logging partition #3. The data record format is assumed to be configured properly
for the partition to store all desirable parameters. Example 4-4 demonstrates how to
program a setpoint for those operations.
Example 4-4 Sample Of Using Time Trigger
Trigger conditions
Conjunction Trigger parameter Condi-
tion
Operate
limit
Release
limit
Condition #1
OR Pulse input #1 ON
Condition #2
AND Day of month = 1
Condition #3
AND Time
≥
000000
Condition #4
AND Time
≤
001459
Setpoint actions
Delays
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