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10090943EN
8.2. Control Functions in the Event of Faults
Extraneous light / premature flame signal
During pre-purge and/or pre-ignition period there must never be a flame signal. If there is a
signal during this period, caused possibly by premature ignition due to a leaking oil valve,
extraneous light, a short-circuit in the flame detector (photo resistor) or its wiring, a fault in the
flame signal amplifier, etc., the control unit locks out on expire of the pre-purging and safety
period. Under these circumstances the oil valve does not open during the safety time.
Non-appearance of the flame signal
If no flame signal has appeared by the end of the safety period, the control unit immediately
locks out.
Flame failure during operation
On flame failure during operation the control unit immediately shuts down the fuel supply and
automatically attempts to restart. On completion of ”t4” the control unit performs the full starting
sequence.
With every lock-out control outputs 3 to 8 and terminal 11 are de-energized in less than 1
second, while terminal 10 for the remote signalling of lock-outs receives voltage. Resetting the
control is possible only when, after lock-out, at least 50 seconds have elapsed.
Protection against under-voltages
The electronic protection against under-voltages ensures that in the event of mains
disturbances with dangerous under-voltages (< 165 V) the control unit shuts down the burner
and prevents a new start-up.
8.3. Technical Data of Control Unit
Supply voltage
220 VAC -15 %...240 VAC +10 %
Protection against under
< 165 V
Frequency
50 - 60 Hz,
±
6 %
External fuse
max. 10A
Permissible ambient temperature
-20...+60
°
C
8.4. Current through Flame Detector
220 VAC
230 VAC
Photo resistor (flame detector) QRB
Min. required detector current with flame
35
μ
A DC
40
μ
A DC
Max. permissible detector current without flame
5
μ
A DC
6
μ
A DC
Max. possible detector current with flame
40
μ
A DC
45
μ
A DC
Internal resistance of the d.c. measuring instrument
max. 5 kOhm (+pole to terminal 12)
