Unigas PBY70 Manual Of Installation - Use - Maintenance Download

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SIEMENS OIL BURNERS AUTOMATIC CONTROLLER SIEMENS
LMO14 - LMO24 - LMO44

The LMO... burner controls are designed for the start-up and supervision
of single- or 2-stage forced draught oil burners in intermittent operation.
Yellow-burning flames are supervised with photoresistive detectors
QRB..., blue-burning flames with blue-flame detectors QRC...
In terms of housing dimensions, electrical connections and flame detec-
tors, the LMO... are identical to the LOA... oil burner controls.

Preconditions for startup



Burner control is reset



All contacts in the line are closed



No undervoltage



Flame detector is darkened, no extraneous light

Undervoltage



Safety shut-down in the operating position takes place should the
mains voltage drop below about AC 165 V



Restart is initiated when the mains voltage exceeds about
AC 175 V

Time supervision oil pre-heater

If the oil pre-heater’s release contact does not close within 10 minutes,
the burner control will initiate lock-out.

Controlled intermittent operation

After no more than 24 hours of continuous operation, the burner control
will initiate an automatic safety shut-down followed by a restart.

Control sequence in the event of fault

If lock-out occurs, the outputs for the fuel valves and the ignition will
immediately be deactivated (< 1 second).

Lock-out

In the event of lock-out, the LMO... remains locked (lock-out cannot be
changed), and the red signal lamp will light up. This status is also maintai-
ned in the case of a mains failure.

Resetting the burner

Whenever lock-out occurs, the burner control can immediately be reset.
To do this, keep control the lock-out reset button depressed for about 1
second (< 3 seconds).

Ignition program with LMO24.113A2

If the flame is lost during «TSA», the burner will be reignited, but not later
than at the end of «TSAmax.». This means that several ignition attempts
can be made during TSA (refer to «Program sequence»).

Limitation of repetitions

If the flame is lost during operation, a maximum of 3 repetitions can be
made. If the flame is lost for the 4th time during operation, the burner will
initiate lock-out. The repetition count is restarted each time controlled
switching on by «R-W-SB» takes place.

Operation

Lock-out reset button «EK...» is the key operating element for
resetting the burner control and for activating / deactivating the
diagnostic functions.

The multicolour «LED» is the key indicating element for both
visual diagnosis and interface diagnosis.

Red

Yellow

Green

Key

Off

Yellow

Green

Red

Diagnosis of cause of fault

After lock-out, the red fault signal lamp remains steady on.
In that condition, the visual diagnosis of the cause of fault according to the
error code table can be activated by pressing the lock-out reset button for
more than 3 seconds.

During the time the cause of fault is diagnosed, the control outputs are
deactivated.



Burner remains shut down



Fault status signal «AL» at terminal 10 is activated

The diagnosis of the cause of fault is quit and the burner switched on
again by resetting the burner control.
Press lock-out reset button for about 1 second (< 3 seconds).

Connection diagram and internal diagram

Cause

Response

After a mains failure

Restart

After voltage has fallen below the
undervoltage threshold

Restart

In the event of a premature, faulty
flame signal during «t1»

Lock-out at the end of «t1»

In the event of a premature, faulty
flame signal during «tw»

Prevention of start-up, lock-
out after no more than 40
seconds

If the burner does not ignite during
«TSA»