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BCU 480 · Edition 03.16l
62
Project planning information
6 .14 Wiring
Electrical connection via plug-in connection terminals
(2.5 mm²) and plug-in cable glands. The latter can be
removed in order to facilitate installation.
The BCU is suitable for hard wiring only. Do not reverse
phase and neutral conductor. Different phases of a
three-phase current system must not be installed at
the BCU.
No voltage may be connected to the valve and ignition
outputs.
No gas valve may be connected to the air valve output
(terminal 26).
See page 13 (Connection diagrams) onwards.
6 .15 BCU and BCU . .E1 (with and without
adapted power management)
The BCU is available as a replacement unit for existing
systems in which a BCU is already in operation.
We recommend using a BCU with power management
(BCU..E1) when planning new systems. It features a
new power management scheme for simplified installa-
tion and control. The power for the ignition transformer
and valves is supplied via the phase (terminal 1) and
must no longer be supplied by the safety interlocks. No
effort and expenditure is thus required for coupling
contactors and their safety devices.
Unit replacement
A BCU without power management may not be re-
placed with a BCU with power management (BCU..E1).
The reverse also applies, i.e. a BCU..E1 may not be re-
placed with a BCU without power management.
6 .16 Signal distributor board
An additional signal distributor board (terminals
30 – 38) can be ordered for wiring additional relays, etc.
(BCU..C).
L1 (L1)
N (L2)
PE
1 2
PE
N1
N1
s
s1
V1 V2
C
N
S
M
L
l
N1
v1
c2
c1
N1
v2
V1
V2
F1
230V~
max. 2 A,
253 V
I
Z
30 31 32 33 34 35 36 37
DI
50 51
l
38
F3
40 41 42 43 44 45 46 47
UVS
1
2
3
P
5
6
7 8
11
9 10
12 13 14 15
25 26 27
18 19 20
22
24
PE
7 8 9 10
24 25
PE
7
8
9
24
A
23
ϑ
3 4
1
ϑ
2
21
2
1
17
16
28 29
Test
O
I
BCU 480..C