Bcu 460 Program Sequence - Honeywell BCU 460 Technical Information

Function
Switch on BCU 460
In the event of fault signal:
reset
Safety interlock (Limits)
00
Start-up position/Standby
If parameter P15 = 1:
flame simulation check
01
Start-up with ϑ signal
Wait until
min. burner pause time t
has elapsed (P21)
If parameter P15 = 0:
flame simulation check
02
Safety time t
running (P22),
ignition in process,
V1 opens and
min. burner on time t
starts to elapse (P20)
If no flame detected:
max. 3 start-up attempts
or fault lock-out
BCU 460, BCU 465 · Edition 03.16l
03
Flame proving period t
BCU 460..L
with air valve control features
the following additional func-
tions.
In start-up position, the air
valve can be opened for cool-
ing
Using parameter 31, it can be
determined whether the air
valve can be activated exter-
nally during start-up.
BP
The air valve can be set to open
SA
together with V1 (display
via parameter 30.
B
FS
.
A
A2
)

3 .4 BCU 460 program sequence

Normal start-up
If an "old" fault is still being signalled after
switching on, it will be necessary to reset
this first.
When the safety interlocks are closed, the
BCU reverts to start-up position and con-
ducts a self-test. If it does not determine
a malfunction of the internal electronic
circuitry or of the flame sensor, the burner
can be started.
The flame simulation check is conducted
during start-up position or after applying
the start-up signal (ϑ), depending on pa-
rameter 15.
After the min. burner pause time t
elapsed, the BCU opens valve V1 and
ignites the burner. The ignition time t
constant.
If a flame is detected during the safety
time t , the flame proving period t
SA
after this safety time has elapsed. Valve V2
opens and the operation signalling contact
between terminals 16 and 17 closes.
▼
has
BP
is
Z
starts
FS
34