Chapter 6—Motor Protection
130
Power Xpert C445 Global Motor Management Relay
MN042003EN—January 2019
www.eaton.com
Motor Thermal Overload
The Overload function models the thermal characteristics of
a motor and generates a Fault Trip event that de-energizes
the motor before motor damage will occur. This is intended
to protect the motor and power wiring from excessive
current. Trip curves are defined by applicable agency
standards. The trip class for any particular Overload class is
user adjustable.
Table 33. Overload
Instantaneous Overcurrent
The Instantaneous Overcurrent protection monitors the
maximum phase current of the motor and will trip the motor
if the current exceeds the set threshold. The Instantaneous
Current protection is active when the motor is energized but
does have a separate Start delay to account for high starting
currents that are characteristic of high efficiency induction
motors.
Table 34. Instantaneous Overcurrent
Fault
Code
Default
Status
Fault Action
Delay (Seconds)
Protection
Action
Units
Note
Min.
Max.
Default
Min.
Max.
Default
19
Thermal Overload
Fault Trip
Enabled
amps
C445MA2P2… 0.3
2.4
0.3
Class 5
Class 40
Class 5
C445MA005… 1
5
1
Class 5
Class 40
Class 5
C445MA032… 4
32
4
Class 5
Class 40
Class 5
C445MA045… 6
45
6
Class 5
Class 40
Class 5
C445MB072…
9
72
9
Class 5
Class 40
Class 5
C445MC090…
11
90
11
Class 5
Class 40
Class 5
C445MC136…
17
136
17
Class 5
Class 40
Class 5
C445…ext
ext
800
ext
Class 5
Class 40
Class 5
Fault Warning
Disabled
%
1
100
90
Overload Reset
Threshold
%
C445… 1
99
75
Fault
Code
Modbus
Fault Action Settings
Delay (Seconds)
Protection
Action
Units
Min.
Max.
Default
Min.
Max.
Default
Modbus
7
Instantaneous
Overcurrent
Fault Trip
1012
% FLA
50
400
400
1
2000
2000
1015
Fault Warning
1013
% FLA
50
400
400
200
5000
2000
1079
Fault Trip Delay
At powerup
0
18000
0
1014
