System Operation
4 Curve sets FMS
(option)
Interconnection with
The FMS offers the optional facility for using 4 curve sets.
4 curve sets option
In this case 2 curve sets are firmly assigned to oil operation and 2 curve sets
to gas operation. The curve sets are then selected via terminal 75 (fuel
selection) and additionally via the fuel safety interlock circuits.
___________________________________________________________________
Fuel
Oil safety
Gas safety
Curve set
selection
interlock circ.
Interlock circ.
terminal 75
terminal 69
terminal 5
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0
1
0
Curve set 1 (oil op.)
0
0
1
Curve set 2 (gas op.)
1
1
0
Curve set 3 (oil op.)
1
0
1
Curve set 4 (gas op.)
X
0
0
FMS does not start or
fault during operation
X
1
1
FMS does not start or
fault during operation
Since the fuel safety interlock circuits now serve here for selection of the curve
set, they are, contrary to the standard flowchart, monitored immediately after
starting (or more precisely after the end of t1, see flow charts) and must
remain on until burner-shut-off
79