BCU 480 · Edition 03.16l
47
Parameters
Restart in the event of flame failure
Parameter 13 = 1: Restart in the event of flame failure.
06
05
07
08
08
t
t
SA2
t
FS2
1x
t
W2
t
SB
>2 s
9
12
V1
1
14
V2
2
2
16-17
1
24
21
88
4
5
1
7
18-19
28-29
ϑ
1
ϑ
2
If the BCU detects a flame failure after a minimum op-
erating time of 2 s, valve V2 is closed and the operation
signalling contact is opened within time t
SB
.
The burner control unit now attempts to restart the
main burner once. If the burner does not function, a
fault lock-out occurs. The display blinks and shows the
cause of the fault.
In accordance with EN 746-2, a restart may be con-
ducted only if the safety of the installation is not im-
paired. Restart is recommended for burners which oc-
casionally display unstable behaviour during operation.
The precondition for a restart is that activation of the
restart allows the burner to restart as intended (in all
operating phases). In this case, it must be ensured that
the program sequence started by the BCU matches the
application.
4 .6 .4 Program status on last fault
Parameter 03
This indicates the program status in which the last
burner fault occurred.
Example: the unit indicates that the safety interlocks
have been interrupted with a blinking
51
.
Parameter 03 can now be used to scan in what program
status the BCU was when the fault was detected.