GE Power Management
469 Motor Management Relay
4-69
4 SETPOINT PROGRAMMING
4.11 S10 POWER ELEMENTS
4
4.11.4 UNDERPOWER
a) FUNCTION
If enabled, once the magnitude of 3
Φ
total power falls below the Pickup Level for a period of time specified by
the Delay, a trip or alarm will occur. The Underpower element is active only when the motor is running and will
be blocked upon the initiation of a motor start for a period of time defined by the
BLOCK ELEMENT FROM START
setpoint (e.g. this block may be used to allow pumps to build up head before the underpower element trips or
alarms). A value of 0 means the feature is not blocked from start. If a value other than 0 is entered, the feature
will be disabled when the motor is stopped and also from the time a start is detected until the time entered
expires. The pickup level should be set lower than motor loading during normal operations.
b) EXAMPLE
Underpower may be used to detect loss of load conditions. Loss of load conditions will not always cause a sig-
nificant loss of current. Power is a more accurate representation of loading and may be used for more sensitive
detection of load loss or pump cavitation. This may be especially useful for detecting process related problems.
y
UNDERPOWER
y
[ENTER] for more
BLOCK UNDERPOWER
FROM START: 0 s
Range: 0 to 15000 sec., step 1
UNDERPOWER
ALARM: Off
Range: Off, Latched, Unlatched
ASSIGN ALARM RELAYS:
Alarm
Range:
Alarm, Alarm & Auxiliary2, Alarm & Aux2 & Aux3,
Alarm & Auxiliary3, Auxiliary2, Aux2 & Aux3, Auxiliary3
UNDERPOWER ALARM
LEVEL: 2 kW
Range: 1 to 25000 kW, step 1
UNDERPOWER ALARM
DELAY: 1 s
Range: 1 to 30 sec., step 1
UNDERPOWER ALARM
EVENTS: Off
Range: On, Off
UNDERPOWER
TRIP: Off
Range: Off, Latched, Unlatched
ASSIGN TRIP RELAYS:
Trip
Range:
Trip, Trip & Auxiliary2, Trip & Aux2 & Aux3,
Trip & Auxiliary3
UNDERPOWER TRIP
LEVEL: 1 kW
Range: 1 to 25000 kW, step 1
UNDERPOWER TRIP
DELAY: 1 s
Range: 1 to 30 sec., step 1
ENTER
ESCAPE
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