FCU 500, FCU 505 · Edition 02.17
104
Parameters
Parameter 75 = 2: MIN. to MAX. capacity; standby in
CLOSED position. The control range while the burner
is operating is between the positions for minimum ca-
pacity (S2) and maximum capacity (S3). The burner is
ignited in the position for ignition capacity (S1). When
the burner is switched off, the actuator is moved to the
closed position (S4).
This operating mode can be achieved with an actua-
tor IC 20 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 stand-
by:
S1: for ignition capacity of the burner.
S2: for minimum 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.
0°
90°
S4
S2
S1
S3
Burner control range
CLOSED
Butterfly valve setting range
Control range
Move to ignition position
Ignition pos.
Max. pos.
OPEN
S4
S2
Min.
pos.
Closed
pos.
MIN
MIN
MAX
MAX
PE
L1
N
3 2 1
16
6
7
4
8
12 11
15
13
S3
S4
S11
S10
0°
90°
M
IC 20
PE
S1
S2
90°
➔
0°
0°
➔
90°
S1
Min
Max
Y-
Y+
1
2
3
46
47
48
49
50
4
67
44
52
45
51
65
66
68
41
42
16
17
18
57
13
14
15
53
54
55
56
58
62 61
5 6 7 8
11 12
FCU 500..F1
5AT
3,15AT
µC
24V
DC
88
▼