Honeywell Krom Schroder BCU 580 Technical Information page 92

Parameters
Parameter 75 = 3: IGNITION to MAX. capacity; standby
in CLOSED position.
The control range while the burner is operating is be-
tween the positions for minimum capacity (S1) and
maximum capacity (S3). The burner is ignited in the
position for minimum capacity (S1). When the burner is
switched off, the actuator is moved to the closed posi-
tion (S4).
This operating mode can be achieved with an actuator
IC 20, RBW or alternatively with a comparable three-
point step actuator.
If the air supply is stopped on a heated furnace with
the burner switched off, the controls are protected
from the hot furnace atmosphere as a result of the
butterfly valve being in the closed position (limited
by S4) . Check whether the burner can cope without
cooling in this situation .
IC 20
Switching cam setting for ignition capacity, minimum and maximum capacity
as well as pre-purge and standby:
S1: for minimum capacity and ignition capacity of the burner.
S3: for maximum capacity of the burner and pre-purge.
S4: for the closed position of the butterfly valve and standby.
BCU 580 · Edition 11.15l
0°
62 61 5 6 7
MIN Burner control range
c
CLOSED Butterfly valve setting range
IGNITION
24V
DC
Move to ignition position
Closed Min. S1
88
Ignition pos.
pos. pos.
µC
BCU 580..F1
16 15 13 12 11
▼
9 10 11 12
MAX
c
OPEN
Control range MAX
3,15AT
Y-
Y+
8 7 6 4 3 2 1
PE
S11
S2 S1
S3
S1
Min Max
90°
S3
Max. pos.
L1
N
PE
S10
S4
92