Honeywell Krom Schroder BCU 580 - Fifth or Switchable Gas Valve on BCU

BCU 580 · Edition 11.15l 111
Project planning information
12.8 Fifth or switchable gas valve on BCU..F3
Units with air valve control have an additional contact
(terminal 53/54), which closes at the same time as the
air valve.
This can be used to activate a fifth gas valve. To do this,
the output of a gas valve must be used as auxiliary en-
ergy (e.g. V2 as a result of the required flame control).
BCU..F3
13 14 15
N
V2
V3
V1
53 54
V5
57
V4
The following application describes a two-stage-con-
trolled burner without a pneumatic air/gas ratio control
system. V2 and the air valve are activated simultane-
ously.
V2 must not be activated during purging.
BCU 580..F3
V1
1513
V2V3 V4
145710
53
54
L1
ϑ1
A
1
2
3
4
ϑ2