Chapter 6—Motor Protection
132
Power Xpert C445 Global Motor Management Relay
MN042003EN—January 2019
www.eaton.com
Current Phase Loss
The Current Phase Loss protection monitors the current
unbalance of the motor and will trip the motor if the
unbalance exceeds the set threshold. The Current Phase
Loss protection is active when the motor is in the Running
state.
If a C445 relay is commissioned to monitor an AC motor, the
current must be fed on all three poles to prevent early
tripping.
Measurement Precondition Imax>50% of FLA, Imin<25% of
FLA, No V Phase Loss (or no voltage option)
Measurement Parameter Current unbalance percent
Table 38. Current Phase Loss
Undercurrent
Undercurrent Trip Level protection monitors the three phase
currents and will fault if the measured current drops below
the set threshold.
Table 39. Undercurrent
Fault
Code
Modbus
Fault Action
Delay (Seconds)
Protection
Action
Units
Min.
Max.
Default
Min.
Max.
Default
Modbus
5
Current Phase Loss Fault Trip
1016
%
60
60
60
2
2
2
1017
Fault
Code
Modbus
Fault Action
Delay (Seconds)
Protection
Action
Units
Min.
Max.
Default
Min.
Max.
Default
Modbus
14
Undercurrent
Fault Trip
1021
% FLA
10
90
50
1
60
20
1023
Fault Warning
1022
% FLA
10
90
50
0.2
5
2
1079
