Honeywell Krom Schroder BCU 580 Technical Information page 79

Parameters
Operating mode 11
Operating mode 11 allows cyclic operation (ON/OFF
and OFF/Low/High/OFF).
The actuator IC moves to the "High fire" position during
the controller enable procedure. There is no timeout ac-
tive in this case.
t 1 t 2
Purge
High
fire
Ignition
Closed
DI 1
DI 2
BCU
Signal at
terminal
Position
55 53
OFF OFF Closed
ON OFF Ignition
ON ON High-fire rate
OFF ON Purge
BCU 580 · Edition 11.15l
t 3 t 4 t 5 t 6
IC 40 (operating mode 11)
Butterfly valve position
Closed
Minimum/Ignition capacity
High-fire rate
Maximum capacity
Operating mode 27
During the controller enable procedure, the actuator
IC 40 can be adjusted infinitely between the positions
for maximum and minimum capacity using its ana-
logue input (terminals 18 and 19). There is no timeout
active in this case.
t 1
Purge
0–20
mA
Ignition
Closed
t [s]
DI 1
DI 2
t [s]
BCU
Signal at
terminal
55 53
OFF OFF
ON OFF
ON ON
OFF ON
▼
t 2 t 3 t 4
IC 40 (operating mode 27)
Position Butterfly valve position
Closed
Ignition Minimum/Ignition capacity
Any position between minimum and
0 – 20 mA
maximum capacity
Purge Maximum capacity
t 5 t 6
t [s]
t [s]
Closed
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