4-16
MM2 Motor Manager 2
GE Power Management
4.3 S2 PROTECTION
4 SETPOINTS
4
For example, given:
Maximum Thermal Capacity = 100% (Overload Trip)
STOPPED MOTOR COOL TIME
= 30 minutes
The time to reach 15% Thermal Capacity Used can be calculated by:
Therefore, the time that must pass until the Thermal Capacity reaches
15% can be calculated as shown:
OVERLOAD TRIP RESET:
MANUAL
Range: MANUAL, AUTO
If this Setpoint is set to
AUTO
, an automatic reset of Overload Trips will
occur after the motor has cooled to a thermal capacity value below
15%. When set to
MANUAL
, the keypad RESET key must be pressed to
reset the trip after the motor has cooled to a thermal capacity value
below 15%.
RESET LOCKOUT USING
RESET KEY: ENABLE
Range: ENABLE, DISABLE
If this setpoint is set to
ENABLE
, the RESET key on the faceplate of the
MM2 will reset all trips providing that the trip condition is not still
present. When set to
DISABLE
, the RESET key on the faceplate will not
reset the three lockout trips (Overload, Ground Fault, and Locked
Rotor); one of the interlock inputs will have to be used to reset these
three trips. Note: when the “Lockout Reset” function is configured, the
RESET key will no longer be able to reset the three lockout trips.
PHASE UNBALANCE
ALARM: ENABLE
Range: ENABLE, DISABLE
When an unbalance in phase currents exceeds the internally set
threshold, an alarm condition will be generated if this value is set to
ENABLE
. The internal threshold is 15% and the unbalance must be
above this threshold for at least 5 seconds for the alarm to occur.
THERMAL CAPACITY
ALARM: OFF %
Range: 1 to 100% or OFF; Step: 1
When the thermal capacity used exceeds the level set, an alarm will be
generated. This alarm can be assigned to a dedicated AUX Relay if
desired.
OPEN CONTROL CIRCUIT
TRIP: ENABLE
Range: ENABLE, DISABLE
In two-wire control applications where a constant start signal is pro-
vided, the MM2 should be configured to trip on an open control circuit.
An Open Control Circuit occurs when feedback on Contactor Status
(terminal 55) stays open when a start operation is executed. This condi-
tion may occur if a control wiring problem develops or because of an
AUX contact failure. The
OPEN CONTROL CIRCUIT TRIP
feature should be
used in conjunction with the
RESET ALARMS USING RESET KEY
function.
Thermal Capacity
100
e
t T
⁄
–
×
=
Thermal Capacity
100
e
t T
⁄
–
×
=
15
100
e
t T
⁄
–
×
=
0.15
⇒
e
t T
⁄
–
t
T
---
⇒
0.15
(
)
ln
–
t
⇒
T
0.15
ln
–
=
=
=
t
⇒
11.4 minutes
=
Summary of Contents for MOTOR MANAGER 2
Page 2: ......
Page 4: ......
Page 34: ...3 8 MM2 Motor Manager 2 GE Power Management 3 3 THEORY OF OPERATION 3 HARDWARE 3 ...
Page 80: ...5 12 MM2 Motor Manager 2 GE Power Management 5 5 A4 STATISTICS 5 ACTUAL VALUES 5 ...
Page 188: ...9 40 MM2 Motor Manager 2 GE Power Management 9 13 SOFT STARTER 9 STARTER TYPES 9 ...
Page 212: ...E 4 MM2 Motor Manager 2 GE Power Management E 1 CT ISOLATION APPENDIXE E ...
Page 220: ...iv MM2 Motor Manager 2 GE Power Management INDEX ...