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BCU 480 · Edition 03.16l
49
Parameters
4 .7 .4 Air valve opens in the case of external
activation (not during start-up)
02
00 A000
t
SA2
A8
07
04
t
t
FS2
06
88
A
18-19
23
26
28-29
12
9
V1
1
14
V2
4
5
2
7
24
2
21
16-17
1
2
t
SA1
t
Z
t
FS1
03
ϑ
1
ϑ
2
VR..R
VAG
UV
BCU 480..L
A
P
L1
1
2
SPS
PLC
CPE
VAS 1
ϑ
Parameter 30 = 0: The air valve opens if it is activated
externally via input 23.
Parameter 31 = 0: The air valve remains closed during
start-up even if it is activated externally.
These settings are required on burners on which the
gas/air ratio is controlled via a pneumatic ratio control
system and which also need to be started at low fire,
e.g. on two-stage-controlled burners. In this case, ac-
tivation of the air valve during burner start via input 23
must be prevented.
External control allows switchover between low fire and
high fire during operation.