Description
2.7 Basic unit
3VA27 molded case circuit breakers & 3WL10 air circuit breakers
40 Manual, 10/2018, L1V30499596002-01
Switch disconnectors are devices that meet the insulation requirements of the standard IEC
60947-3 and IEC 60947-2 CBI-Y Annex L.
The switch disconnector has an identical design to the circuit breaker and has the same
dimensions, weights, and optional accessories. However, it differs from the circuit breaker in
that it does not have any protection functions and therefore no electronic trip unit (ETU) and
no internal electronics or current transformer.
The disconnector ensures an insulation clearance between its main contacts in the open
state that isolates all downstream parts of the installation.
If used with an external protection relay with a maximum delay time of 500 ms, the switch
disconnector has a breaking capacity at the maximum rated operational voltage (U
e
) that
corresponds to the value of the one-second rated short-time current (I
cw
). The "non-
automatic air circuit breaker" is sometimes also called a load interrupter switch because it
can switch overcurrents.
3WL10 non-automatic air circuit breakers
3WL10 non-automatic air circuit breakers are only available in classes N and S.
Rated operational
U
e
AC (50/60 Hz) V 690
Rated insulation
U
i
AC (50/60 Hz) V 1000
Rated impulse
U
imp
kV 12
Current-carrying capacity of the
neutral pole for 4-pole non-
automatic
% I
n
100
Rated uninterrupted current
(at 40 °C)
u
u
Rated short-circuit
making capacity up to 690 V
I
cm
with upstream ACB
kA 145 145
Rated short-time
withstand current
cw
Utilization category
(according to IEC 60947-3)
AC-23A AC-23A
Rated conditional
short-circuit current
I
cc
kA 42 50
To Next Page
Loading...
