BCU 460, BCU 465 · Edition 11.19
73
Parameters
11 .4 Flame control
The BCU is fitted with two OR-linked flame amplifiers,
each of which evaluates whether an adequate flame
signal is supplied by the burner to the flame amplifier
using a flame rod or UV sensor.
11 .4 .1 Burner 1 flame signal FS1 switch-off
threshold
Parameter A001
The sensitivity at which the burner control unit detects
a flame can be set using parameter A001.
As soon as the measured flame signal falls below the
set value (2 to 20
�
A), the BCU performs a fault lock-
out during start-up after the elapse of the safety time or
during operation after the elapse of the safety time dur-
ing operation (parameter A019).
In the case of UV control, this value can be increased,
should the burner to be monitored be influenced by
other burners, for example.
The adjustable range for the flame signal switch-off
threshold for burner 1 is dependent on the setting of
interface parameter I004 (Flame control):
I004 = 0 (ionization control): 2 – 20
µ
A,
I004 = 1 (control using UVS sensor): 5 – 20
µ
A,
I004 = 2 (control using UVC sensor): 5
µ
A
11 .4 .2 Burner 2 flame signal FS2 switch-off
threshold
Parameter A002
The sensitivity at which the burner control unit still
detects a flame at burner 2 can be set using param-
eter A002.
As soon as the measured flame signal falls below the
set value (2 to 20
�
A), the BCU performs a fault lock-
out during start-up after the elapse of the safety time or
during operation after the elapse of the safety time dur-
ing operation (parameter A019).
In the case of UV control, this value can be increased,
should the burner to be monitored be influenced by
other burners, for example.
The adjustable range for the flame signal switch-off
threshold for burner 2 is dependent on the setting of
interface parameter I004 (Flame control):
I004 = 0, 5 or 7
(ionization control of burner 2): 2 – 20
µ
A,
I004 = 1, 3 or 8
(control of burner 2 using UVS sensor): 5 – 20
µ
A,
I004 = 2, 4 or 6
(control of burner 2 using UVC sensor): 5
µ
A