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BCU 580 · Edition 11.15l
106
Project planning information
12 .3 .2 Safety current inputs
Actuation of the safety current inputs only with switch-
gear featuring mechanical contacts. If switchgear with
semi-conductor contacts is used, the safety current
inputs must be connected using relay contacts.
To safeguard the safety current inputs, the fuse must be
designed so that the sensor with the lowest switching
capacity is protected.
The cabling outside enclosed installation spaces must
be protected from mechanical damage and stress (e.g.
vibration or bending) as well as short-circuits, short-
circuits to ground and cross-circuits.
17
18
37
38
N
max. 1 A;
24 V DC,
250 V AC
BCU 580
3,15AT
µC
88
c
c
0 V
+24 V
41
42
24V
DC
9
11 12
10
62 61
230V
1
2
3
4
L1
ϑ1
P70
ϑ2
P70
P70
P69
P73
P72
P72
HT
p
u
2
GZL
PZL
P71
0,6 × I
N
46
45
65
66
67
68
49
50
51
5 6 7 8
13
14
15
57
V1
V2
V3
V4
A
53
54
55
56
P
M
I
Calculation
I
N
= current of the sensor/contactor with the lowest
switching capacity
Suitable fuse = 0.6 × I
N