Trip Units
PowerPact B-frame circuit breakers offers a fixed, factory-sealed thermal-magnetic trip unit designed to open automatically under overload or short circuit conditions.
B-frame thermal-magnetic circuit breakers contain individual thermal (overload) and instantaneous (short circuit) sensing elements in each pole.
AC Magnetic Trip Levels
Ii |
Rated Current (A) |
||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
15 |
20 |
25 |
30 |
35 |
40 |
45 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
125 |
|
Hold (A) |
400 |
400 |
400 |
400 |
400 |
400 |
400 |
480 |
640 |
640 |
800 |
1000 |
1000 |
1000 |
1000 |
Trip (A) |
600 |
600 |
600 |
600 |
600 |
600 |
600 |
720 |
960 |
960 |
1200 |
1500 |
1500 |
1500 |
1500 |
DC Magentic Trip Levels
The Time Current Curves (trip curves) provide the complete time-current characteristics of the circuit breaker when applied on an AC system. When applying thermal-magnetic circuit breakers on DC systems, they retain the same thermal tripping characteristics, but the magnetic trip levels vary. See table for the appropriate DC magnetic hold and trip levels.
Ii |
Rated Current (A) |
||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
15 |
20 |
25 |
30 |
35 |
40 |
45 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
125 |
|
Hold (A) |
460 |
460 |
510 |
510 |
510 |
510 |
510 |
510 |
790 |
900 |
900 |
1200 |
1200 |
1200 |
1200 |
Trip (A) |
680 |
680 |
800 |
800 |
800 |
800 |
800 |
800 |
1240 |
1420 |
1420 |
1850 |
1850 |
1850 |
1850 |