GE MOTOR MANAGER 2 User Manual

7-4 MM2 Motor Manager 2
GE Power Management
7.2 FUNCTIONAL TESTS 7 TESTING
7
7.2.2 UNBALANCE EXAMPLES
a) EXAMPLE #1
Find the percentage unbalance given the following information:
We have
I
av
given by:
Since
I
av
< I
fl
, the following formula is used:
Since the unbalance is greater than 15%, an UNBALANCE alarm will occur if this condition persists
for longer than 5 seconds and the AUX Relay 1 will energize.
b) EXAMPLE #2
Find the percentage of unbalance given the following information:
We have
I
av
given by:
Since
I
av
> I
fl
, the following formula is used:
Since unbalance is greater than 30%, a SINGLE PHASE trip will occur if this condition persists for
longer than 5 seconds and the AUX Relay 2 will energize.
VALUE PRIMARY SECONDARY (5A)
I
a
73 A 3.65 A
I
b
100 A 5 A
I
c
100 A 5 A
VALUE PRIMARY SECONDARY (5A)
I
a
100 A 5 A
I
b
80 A 4 A
I
c
150 A 7.5 A
I
av
I
a
I
b
I
c
++
3
-------------------------
73 100 100 A
++
3
---------------------------------------------
273
3
----------
A = 91 A
== =
% unbalance
I
n
I
av
–
I
fl
--------------------
100
×
73 91
–
100
----------------------
100
×
18%
== =
I
av
I
a
I
b
I
c
++
3
-------------------------
100 80 150 A
++
3
---------------------------------------------
330
3
----------
A = 110 A
== =
% unbalance
I
n
I
av
–
I
fl
--------------------
100
×
150 110
–
100
----------------------------
100
×
40 %
== =

GE MOTOR MANAGER 2 Specifications

General

Brand	GE
Model	MOTOR MANAGER 2
Category	Controller
Language	English