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BCU 580 · Edition 11.15l
25
Air control
4 Air control
A central protective system such as the FCU 500 takes
over air control. It monitors the static air pressure as
well as the air volume required for pre-purge, start-up
and after the furnace has been shut down. The air ac-
tuators (BCU..F1 = actuators IC 20/40, BCU..F2 = RBW
actuators, BCU..F3 = valve) are actuated for this pur-
pose by the capacity control system of the BCU.
After being enabled by the protective system, the BCU
can start the burners. The capacity is controlled during
operation by an external temperature control system.
VAS
M
PZL
PZH
PZ
PZL
PDZ
TE
BCU 580..F3
FCU 500..F0
µC
P
DG
DG
DG
VAS
VAS
VAG
VAS
VAS
VR..L
VR..L
DG
DG
DG
min
DG
max
49
15
13
14
50
45
47 48
58
>750°
p
u
/2
ϑ
1
46
2
3
DL
min
DL
Purge
BCU 580..F3
VAG
VAS
VAS
M
PZL
PDZ
BCU 580..F3
FCU 500..F0
µC
P
VR..L
VR..L
DG
DG
49
15
13
14
50
45
47 48
58
>750°
ϑ
1
46
2
3
DL
min
DL
Purge
BCU 580..F3
M
STM