Capacity Control (Bus) - Honeywell Krom Schroder BCU 580 Technical Information

Parameters

10 .6 .9 Capacity control (bus)

Parameter 75
Controlling the burner capacity using the fieldbus is
only possible with bus module BCM 500 connected
and enabled (P80 = 1 or 2).
The output at terminal 56 has a different function.
Parameter 75 = 0: Off. No capacity control possible us-
ing the fieldbus.
Parameter 75 = 1: MIN. to MAX. capacity; standby in
position for MIN. capacity. The control range while
the burner is operating is between the positions for
minimum capacity (S4) and maximum capacity (S3).
The burner is ignited in the position for ignition capac-
ity (S1). When the burner is switched off, the actuator is
moved to the position for minimum capacity (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 may be dam-
aged by the hot furnace atmosphere as a result of the
lowest possible position of the butterfly valve, limited
by S4 .
IC 20
Switching cam setting for ignition capacity, minimum and maximum capacity
as well as pre-purge and standby:
S1: for ignition capacity of the burner.
S3: for maximum capacity of the burner and pre-purge.
S4: for minimum capacity of the burner and standby.
BCU 580 · Edition 11.15l
0°
62 61 5 6 7 9
MIN Burner control range
c
c
MIN Butterfly valve setting range
S4
MIN
24V
DC
Move to ignition position
Closed Min. S1
88
pos. pos.
Ignition pos.
µC
BCU 580..F1
16 15 13 12 11
S1
Min
▼
10 11 12
MAX
MAX
Control range MAX
3,15AT
Max. pos.
Y-
Y+
8 7 6 4 3 2 1
PE
S11
S2 S1
S3
Max
90°
S3
L1
N
PE
S10
S4
90