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3VT2 Molded Case Circuit Breakers up to 250 A
Project planning aids
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Siemens LV 36 · 2008
3
■
Dimensional drawings
Use of insulating barriers and terminal covers with circuit
breakers and switch disconnectors
Fixed-mounted design
Front connection
• terminals 1, 3, 5
a) If U
e
= AC 415 V, it is necessary to use 3VT9 300-8CE30
insulating barriers or a 3VT9 200-8CB30 terminal cover.
b) If insulated conductors are not used for connecting main
circuit to terminals 1, 3, 5, flexibars or rear connection, it is
necessary to use 3VT9 300-8CE30 insulating barriers or a
3VT9 200-8CB30 terminal cover.
• terminals 2, 4, 6
- Only in case that the circuit breaker/switch disconnector is
connected to the source using terminals 2, 4, 6 and further-
more:
a) If U
e
AC 415 V, it is necessary to use 3VT9 300-8CE30
insulating barriers or a 3VT9 200-8CB30 terminal cover;
b) If insulated conductors are not used for connecting main
circuit to terminals 2, 4, 6, flexibars or rear connection, it is
necessary to use 3VT9 300-8CE30 insulating barriers or a
3VT9 200-8CB30 terminal cover.
Rear connection
• Insulating barriers or terminal covers need not be used.
Plug-in and withdrawable devices
Insulating barriers or terminal covers need not be used.
NSO0_00105
A
A1
A2
B = 105
C = 80
225
20
B = 20
105
105
105
B = 20
3VT9 200-8CB30
D
B = 0
C = 0
TEST
2 4 6
ON
OFF
1 3 5
TEST
2 4 6
ON
OFF
1 3 5
TEST
2 4 6
ON
OFF
1 3 5
100 … 150
1
1
1
A
minimum distance between the circuit breaker/switch-
disconnctor and uninsulated earthed wall (applicable for
connections using insulated conductors, cables, flexibars
or with rear connection)
A1
minimum insulation length of bare conductors (using
3VT9 300-8CE30 insulating barriers from 50 mm to max.
100 mm, or by adding additional insulation for the con-
ductors with barriers to obtain at least A1 value)
A2
minimum distance:
• between circuit breaker/switch disconnector and uninsu-
lated earthed wall (applicable for uninsulated conduc-
tors and busbars)
• between circuit breaker/switch disconnector and busbar
• between two circuit breaker/switch disconnectors situat-
ed vertically above one another
• between uninsulated connections of two circuit break-
ers/switch disconnectors above one another
B, C minimum distance between circuit breaker/switch discon-
nector and uninsulated earthed wall
D
minimum distance between uninsulated conductors