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BCU 580 · Edition 11.15l
100
Parameters
10 .10 Functions of terminals 50, 51, 65, 66, 67
and 68
The BCU is informed via terminal 50 by a separate au-
tomation system that purging is currently being per-
formed.
Terminals 51, 65, 66, 67 and 68 can each be assigned a
logical AND gating with one of the inputs for the safety
functions (terminals 46 – 50) using an appropriate pa-
rameter. If AND gating is required, the input concerned
can be enabled.
Terminal 51 can also be used as a feedback input for
the maximum capacity position when operated with
IC 40/RBW.
10 .10 .1 Function of terminal 50
Parameter 68
The BCU..F1, F2 or F3 supports centrally-controlled
pre-purge or post-purge. In the case of multiple burner
applications, burners with mechanical combustion air
supply are used. The air for combustion and pre-venti-
lation is supplied by a central fan controlled by a sepa-
rate automation system. The automation system sends
a signal to terminal 50 during purging. At this point, the
BCU opens the air actuator (actuator, air valve) regard-
less of the status of the other inputs. The display shows
P 0
.
Parameter 68 = 23: purge with Low signal.
Parameter 68 = 24: purge with High signal.
10 .10 .2 Function of terminal 51
Parameter 69
Parameter 69 = 0: Off.
Parameter 69 = 8: AND with input at terminal 46 (emer-
gency stop).
Parameter 69 = 13: Max. capacity position feedback
(IC 40/RBW), see page 81 (Parameter 40 = 3: with
RBW.).
10 .10 .3 Function of terminal 65
Parameter 70
Parameter 70 = 0: Off.
Parameter 70 = 8: AND with input at terminal 46 (emer-
gency stop).