BFI Automation 3016, Original Operating Instructions

Page: 38 / 56

Description
5-4
5.5 Switch-Off time
The switch-off time is the time between flame
failure and drop-out of the flame relay. This time
is adjustable by means of a turn-switch (S 2) The
switch is situated on the main PCB, i.e. the plug-
in unit has to be removed from the rack for this
purpose. The selected adjustment should ensure
a fast reaction without limiting the availability.
The adjustment therefore depends on the time
stable intensity level or whether there are severe
fluctuations. In case of fluctuations a longer
switch-off time has to be chosen to compensate
short signal fall-outs in order to avoid an unde-
sired switch-off.
The adjustable switch-off times are listed below:
Switch pos. Time OFF
[ms]
0 200
1 250
2 300
3 350
4 400
5 450
6 500
7 550
8 600
9 650
Table 5.5
During selftest phase the flame scanner sensor is switch-
ed off, whereby the signal evaluation at the flame amplifi-
er is paused for 200 ms.
In case the self test starts im-
mediately after a flame loss the switch-off time can be
prolonged by maximum 250 ms.