Behaviour During Operation; Safety Time During Operation T; Burners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Sb For Pilot And Main; Fault Lock-Out Or Restart, Pilot Burner - Honeywell Krom Schroeder BCU 480 Manual

Parameters

4 .6 Behaviour during operation

4 .6 .1 Safety time during operation t

main burners
Parameter 14
This indicates the safety time during operation t
valves V1 and V2.
The default in accordance with EN 298 is 1 s.
The BCU has also the available option of a safety time
during operation t of 2 s. Prolonging the time in-
SB
creases the installation availability in the case of brief-
duration signal fades (e.g. fades of the flame signal).
In accordance with EN 746-2, the safety time of the
installation during operation (including closing time of
the valves) may not exceed 3 s. (Note the requirements
of the Standards!)

4 .6 .2 Fault lock-out or restart, pilot burner

Parameter 12
This parameter determines whether the BCU initiates a
one-off restart or performs an immediate fault lock-out
for the burner after a flame failure (see also page 57
(Project planning information)).
Immediate fault lock-out in the event of flame
failure
Parameter 12 = 0: Pilot burner fault lock-out.
BCU 480 · Edition 03.16l
for pilot and
SB
for
SB
After a fault lock-out, the burner control unit can be
reset, either with the button on the front panel or using
an external button. Several burner control units can be
reset in parallel using the external button.
The BCU cannot be reset by mains failure. The fault
signalling contact does, however, open as soon as the
mains voltage fails.
See also parameter 32, page 54 (Behaviour of the air
valve in the event of a fault lock-out).
04 04
t
SB
▼
88
1
5
4
1
7
9
1
12
V1
14
V2
16-17
1
18-19
t
44