Overload Alarm; Mechanical Jam - GE MOTOR MANAGEMENT RELAY 469 Instruction Manual

4 SETPOINT PROGRAMMING
S OVERLOAD ALARM
S [ENTER] for more
If enabled as "Latched" or "Unlatched", the Overload Alarm functions as follows. After a motor start, when the
equivalent motor heating current exceeds the OVERLOAD PICKUP LEVEL, an alarm will occur. If programmed as
Unlatched , the overload alarm resets itself when the motor is no longer in overload. If programmed as "Latched",
RESET
the key must be pressed to reset the alarm once the overload condition is gone. Event recording for all
alarm features is optional.
For example, it may be desirable to have an unlatched alarm connected to a PLC that is controlling the load on
a motor.
S MECHANICAL JAM
S [ENTER] for more
If turned On, the Mechanical Jam element function as follows. After a motor start, a Trip occurs once the mag-
nitude of Ia, Ib, or Ic exceeds the Pickup Level × FLA for a period of time specified by the MECHANICAL JAM
DELAY setpoint. This feature may be used to indicate a stall condition when running. Not only does it protect the
motor by taking it off-line quicker than the thermal model (overload curve), it may also prevent or limit damage
to the driven equipment if motor starting torque persists on jammed or broken equipment.
The MECHANICAL JAM PICKUP level should be set higher than motor loading during normal operation, but lower
than the motor stall level. Normally the delay is set to the minimum time delay or set so that no nuisance trips
occur due to momentary load fluctuations.
GE Power Management
ð
OVERLOAD
ENTER
ALARM: Off
ESCAPE
ASSIGN ALARM RELAYS:
ESCAPE
Alarm
MESSAGE

OVERLOAD ALARM

ESCAPE
DELAY: 0.1 s
MESSAGE
OVERLOAD ALARM
ESCAPE
EVENTS: Off
MESSAGE
ð

MECHANICAL JAM

ENTER
TRIP: Off
ESCAPE
ASSIGN TRIP RELAYS:
ESCAPE
Trip
MESSAGE
MECHANICAL JAM
ESCAPE
PICKUP: 1.50 x FLA
MESSAGE
MECHANICAL JAM
ESCAPE
DELAY: 1 s
MESSAGE
469 Motor Management Relay
4.7 S6 CURRENT ELEMENTS
4.7.2 OVERLOAD ALARM
Range: Off, Latched, Unlatched
Range: Alarm, Auxiliary2, Auxiliary3, Alarm & Aux2,
Alarm & Aux3, Aux2 & Aux3, Alarm & Aux2 & Aux3
Range: 0.1 to 60 sec., step: 0.1
Range: On, Off
Range: Off, Latched, Unlatched
Range: Trip, Trip & Auxiliary2, Trip & Aux2 & Aux3;
Trip & Auxiliary3
Range: 1.01 to 3.00 x FLA, step 0.01
Range: 1 to 30 sec., step 1
4.7.3 MECHANICAL JAM
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