Manual

Page 34
The
AL1
If AL
ends
SPSA
If AL
A1t
A1rE
A1P
A1iH
A1St
example if a low alarm isrequired to be 5 degrees below the Set Point, then set
A1Lo to -5. If a high alarm is required 20 degrees above the Set Point, then set
A1Hi to +20. If the Set Point is changed, the alarm will continue to hold the same
relationship as originally set.
The diagram below shows the action and reset functions for both absolute
and deviation alarms.
Note that when Alarm Power Interrupt, A1Pi, is programmed ON and Alarm
Reset, A1rE, is programmed for Hold, the alarm will automatically reset
upon a power failure and subsequent restoration if no alarm condition is
present.
If Alarm Inhibit, A1iH, is selected ON, an alarm condition is suspended
upon power up until the process value passes through the alarm set point
once. Alarm inhibit can be restored as if a power up took place by pressing
both the INDEX and ENTER keys for 3 seconds.
WARNING: IF INHIBIT IS ON AND A POWER FAILURE OCCURS
DURING A HIGH ALARM, RESTORATION OF POWER WILL NOT
CAUSE THE ALARM TO OCCUR IF THE PROCESS VALUE
DOES NOT FIRST DROP BELOW THE HIGH ALARM SETTING.
DO NOT USE THE ALARM INHIBIT FEATURE IF A HAZARD IS
CREATED BY THIS ACTION. BE SURE TO TEST ALL COMBINA
TIONS OF HIGH AND LOW ALARM INHIBIT ACTIONS BEFORE
PLACING CONTROL INTO OPERATION.
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