5–60
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
be increased if nuisance tripping occurs.
When a motor starts, the starting current (typically 6 × FLA for an induction motor) has an
asymmetrical component. This asymmetrical current may cause one phase to see as
much as 1.6 times the normal RMS starting current. If the
SHORT CIRCUIT TRIP PICKUP
was
set at 1.25 times the symmetrical starting current, it is probable that there would be
nuisance trips during motor starting. A rule of thumb has been developed over time that
short circuit protection at least 1.6 times the symmetrical starting current value. This
allows the motor to start without nuisance tripping.
The overreach filter removes the DC component from the asymmetrical current present at
the moment of fault. This eliminates overreach; however, the response time slows slightly
(10 to 15 ms) but remains within specification.
5.7.2
Overload Alarm
PATH: SETTINGS
ZV
S6 CURRENT ELEM.
ZV
OVERLOAD ALARM
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”, the
RESET
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.
5.7.3
Mechanical Jam
PATH: SETTINGS
ZV
S6 CURRENT ELEM.
ZV
MECHANICAL JAM
OVERLOAD
[
OVERLOAD
ALARM: Off
Range: Off, Latched, Unlatched
MESSAGE
ASSIGN ALARM
RELAYS:
Range: Alarm, Auxiliary2, Auxiliary3,
Alarm & Aux2, Alarm & Aux3,
Aux2 & Aux3, Alarm & Aux2 &
Aux3
MESSAGE
OVERLOAD ALARM
DELAY: 0.1 s
Range: 0.1 to 60 s in steps of 0.1
MESSAGE
OVERLOAD ALARM
EVENTS: Off
Range: On, Off
MECHANICAL
[
MECHANICAL JAM
TRIP: Off
Range: Off, Latched, Unlatched
MESSAGE
ASSIGN TRIP
RELAYS:
Range: Trip, Trip & Auxiliary2, Trip &
Aux2 & Aux3, Trip & Auxiliary3
MESSAGE
MECHANICAL JAM
PICKUP: 1.50 x
Range: 1.01 to 3.00 x FLA in steps of
0.01
MESSAGE
MECHANICAL JAM
DELAY: 1 s
Range: 1 to 30 s in steps of 1
Summary of Contents for 469
Page 62: ...2 16 469 MOTOR MANAGEMENT RELAY INSTRUCTION MANUAL CHAPTER 2 INTRODUCTION ...
Page 90: ...3 28 469 MOTOR MANAGEMENT RELAY INSTRUCTION MANUAL CHAPTER 3 INSTALLATION ...
Page 292: ...6 42 469 MOTOR MANAGEMENT RELAY INSTRUCTION MANUAL CHAPTER 6 ACTUAL VALUES ...
Page 313: ...A APPENDIX 469 MOTOR MANAGEMENT RELAY INSTRUCTION MANUAL A 7 HGF5C 808841A1 HGF8 808842A1 ...
Page 315: ...A APPENDIX 469 MOTOR MANAGEMENT RELAY INSTRUCTION MANUAL A 9 808712A1 CDR ...
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