FCU 500, FCU 505 · Edition 02.17
13
FCU 500..F0
µC
P
49
15
13
14
50
45
47
58
48
PZL
PZH
PZ
PZL
PDZ
M
BCU
V1
BCU
V1
FCU 505..F1
µC
54 55
53
M
1
2
3
BCU
V1
BCU
V1
FCU 505..F1
µC
54 55
53
1
1
66
66
46
46
67
+24V
L1
+24V
L1
M
57
17
4
4
Application
1 .1 .5 Furnace and zone control
The FCU 500 (furnace FCU) performs central tasks
such as checking the safety interlocks, fan control, sys-
tem leak tightness check and pre-purge.
It signals to the FCU 505 in the zones that the butterfly
valves can be moved to the purge position. Signals are
sent to the butterfly valves by the FCU 505. The but-
terfly valves move into position. A signal is sent to the
FCU 505 via their safety interlock input that the central
FCU 500 has issued the enable signal for the burners.