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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
detectors, 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).
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»
Lock-out at the end of TSA
In the event the flame is lost during
operation
Max. 3 repetitions, followed
by lock-out
Oil pre-heater’s release contact does
not close within 10 min.
Lock-out
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 maintained 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.
s red
l yellow
o green
Colour code table
Status Colour
code
Colour
Oil pre-heater heats,
waiting time «tw»
lllllllllll Yellow
Ignition phase, ignition
controlled
lmlmlmlmlml Yellow-off
Operation, flame o.k.
oooooooooooo
Green
Operation, flame not o.k. omomomomomo
Green-off
Undervoltage lslslslslsl
Yellow-red
Fault, alarm
sssssssssss
Red
Output of fault code
(refer to Fault code table)
smsmsmsmsm Red-off
Extraneous light prior to
burner start-up
osososososo Green-red
Interface diagnosis
ssssssssssssss
Red flicker light
Key
m Off
l Yellow
o Green
s 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.
Error code table
Blink code
Possible cause
2 blinks **
No establishment of flame at the end of TSA
l Faulty or soiled fuel valves
l Faulty or soiled flame detector
l Poor adjustment of burner, no fuel
l Faulty
ignition
3 blinks ***
Free
4 blinks ****
Extraneous light on burner startup
5 blinks *****
Free
6 blinks ******
Free
7 blinks *******
Too manny losses of fleme during operation
(limitattion og the number of repetitions)
l Faulty or soiled fuel valves
l Faulty or soiled flame detector
l Poor adjustment of burner
8 blinks ********
Time supervision oil pre-heater
9 blinks *********
Free
10 blinks **********
Wiring error or internal error, output contacts
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).
