GE Power Management PQM Power Quality Meter 4-35
4 PROGRAMMING 4.4 S3 OUTPUT RELAYS
4
4.4.2 ALARM RELAY
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ALARM OPERATION:
The terms āfailsafeā and ānon-failsafeā are defined above as implemented in the
PQM. If an alarm is required when the PQM is not operational due to a loss of control power, select failsafe
operation. Otherwise, choose non-failsafe.
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ALARM ACTIVATION:
If an alarm indication is required only while an alarm is present, select unlatched.
Once the alarm condition disappears, the alarm and associated message automatically clear. To ensure all
alarms are acknowledged, select latched. Even if an alarm condition is no longer present, the alarm relay
and message can only be cleared by pressing the key or by sending the reset command via the
computer.
4.4.3 AUXILIARY RELAYS
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AUXILIARY 1, 2, 3 OPERATION:
The terms āfailsafeā and ānon-failsafeā are defined above as implemented
in the PQM. If an output is required when the PQM is not operational due to a loss of control power, select
failsafe auxiliary operation, otherwise, choose non-failsafe.
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AUXILIARY 1, 2, 3 ACTIVATION:
If an auxiliary relay output is required only while the selected conditions
are present, select unlatched. Once the selected condition disappears, the auxiliary relay returns to the
non-active state. To ensure all conditions are acknowledged, select latched. If the condition is no longer
present, the auxiliary relay can be reset by pressing the key or by sending the reset command via
the computer.
Since the relays can be assigned to perform many different functions, the PQM uses a priority system
to determine which function will control the relays if they happen to be assigned to more than one
function. The Table below shows the priority of the functions.
For example, if one of the relays is assigned to an alarm function and it is also assigned to one of the pulse
output parameters, the relay will respond only to the pulse output function.
Table 4ā4: AUXILIARY RELAYS ACTIVATION PRIORITY
PRIORITY FUNCTION
HIGHEST PULSE OUTPUT
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ANALOG INPUT MAIN/ALT SELECT
LOWEST ALL ALARM FUNCTIONS
RESET
NOTE