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BCU 580 · Edition 11.15l
108
Project planning information
12 .4 Actuators
If actuators are used, the start gas rate of the burners
must be limited for SIL 3 applications in compliance
with the standard.
TZI/TGI
VAS
VAS 1
VAG
IC 40 + BVA
V1
V2
V3
V4
VAS 1
4
10
12
7
16
12
M
µC
BCU 580..C0F2
µC
38
37
18
17
1
2
3
FCU 500
Process control (PCC)
46
49
50
P
HT
A
ϑ
1
9
13
14
15
57
8
5
53 55 51 52
4
41
42
43
1
2
ϑ
2
t
1
2
04
04
02–04 06–08
06–08
ϑ
1
ϑ
2
PLC
12 .4 .1 IC 20
The BCU..F1 checks the position to which the actuator
IC 20 has moved using terminal 52 (feedback) by lifting
the signal to terminal 53, 54 or 55, see page 129 (Lift-
ing).
To ensure this check is possible, BCU..F1 and actuator
IC 20 or equivalent three-point step actuators must be
wired as shown in the connection diagram.
I
17
18
37
38
N
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
52
P
M