7
System pro
M
tripping characteristics: B
tripping characteristics: C
I
n
= 6 ... 63 A
I
n
= 0.5 ... 63 A
MCB S 280
MCB S 280
tripping characteristics: K
tripping characteristics: Z
I
n
= 0.2... 63 A
I
n
= 0.5... 63 A
MCB S 280
MCB S 280
Attention: Deviating ambient temperatures and mutual interference
must also be taken into account.
SK 0128 Z 00
SK 0038 Z 01
SK 0144 Z 00
Miniature circuit-breakers
S 280 UC series
Tripping characteristic charts
Reading example for tripping
characteristic of type B
(in connection with the Tripping
Behavior table on page 95, line
B
)
a
Thermal tripping characteristic:
conventional non-tripping current I
1
= selected non-tripping current.
The MCB maintains 1.13 times
the rated current for at least
60 minutes.
Convetional tripping current I
2
= selected tripping current
The MCB switches off within
60 minutes when 1.45 times
the rated current is reached.
b
Electromagnetic
tripping characteristic AC:
The MCB maintains current rushes
exceeding 3 times the rated current
for more than 0.1 sec. (in this example
up to ca. 4 sec.).
The MCB switches off within less than
0.1 sec. when 5 times the rated current
is reached..
SK 0146 Z 00
