TM-G Thermal-Magnetic Trip Unit for 3P and 4P Circuit Breakers up to 250 A
Introduction
The TM-G thermal-magnetic trip unit for 3P/4P circuit breakers up to 250 A are interchangeable trip units.
They are designed for DC general-purpose applications.
The TM-G interchangeable 3P/4P trip units provide:
-
adjustable thermal threshold
-
fixed magnetic pick-up
Description
The adjustment dial is on the front of the trip unit.
A Setting range for the TM-G thermal-magnetic trip unit
B Adjustment dial for the thermal protection pick-up Ir
Setting the Thermal Protection
The thermal protection pick-up Ir is set by a 4-setting dial.
Turning the thermal protection adjustment dial (A) modifies the trip curve as shown (B).
The following table shows the values of the pick-up Ir (in amperes) for thermal protection (values indicated on the dial) with respect to every trip unit rating, relative to the position of the dial Ir.
|
Trip Unit Rating In (A) |
|||||||||
|---|---|---|---|---|---|---|---|---|---|
|
16 |
25 |
40 |
63 |
80 |
100 |
125 |
160 |
200 |
250 |
|
Pick-up Ir (A) |
|||||||||
|
11 |
18 |
28 |
44 |
56 |
70 |
88 |
112 |
140 |
175 |
|
13 |
20 |
32 |
50 |
64 |
80 |
100 |
128 |
160 |
200 |
|
14 |
23 |
36 |
57 |
72 |
90 |
113 |
144 |
180 |
225 |
|
16 |
25 |
40 |
63 |
80 |
100 |
125 |
160 |
200 |
250 |
Setting the Magnetic Protection
The magnetic protection pick-up cannot be adjusted and equals the value shown below:
|
Trip Unit Rating In (A) |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
16 |
25 |
40 |
63 |
80 |
100 |
125 |
160 |
200 |
250 |
|
|
Fixed Pick-up Ii (A) +/– 20% |
||||||||||
|
AC value |
63 |
80 |
80 |
125 |
200 |
320 |
440 |
440 |
440 |
520 |
|
DC value |
80 |
100 |
100 |
150 |
240 |
380 |
530 |
530 |
530 |
620 |