for single- or two-stage pressure-jet burners
with intermittent operation
1)
118
7
LOA2...
LOA2...
Burner controls for automatic startup, control and supervision of pressure-jet oil
burners with an oil throughput of up to 30 kg / h.
The burner controls are tested to EN 230 and CE-certified in compliance with the
directives for electromagnetic compatibility.
The LOA2... / LOA3... and this data sheet are intended for use by OEMs that
integrate the burner controls in their products!
The burner controls are of plug-in design. The casing is made of impact-proof and heatresistant plastic and accommodates the
– thermal-electric sequence switch which acts on a multiple snap-action switching
system
– flame signal amplifier with the flame relay
– lockout reset button with integrated fault indication lamp
Burner controlrefer to table overleaf
Flame detectors
– Photo-resistive detectors QRB1...refer to data sheet 7714
– Blue-flame detectors QRC1...refer to data sheet 7716
Plug-in base, without cable gland holder or without cable holder
– With screw terminalsAGK11
Plug-in base, for clip connection
– Clipses (single pieces in lots of 100)
– Clipses (10,000 pieces on strap)
– Mounting tool
– Removal tool
Cable gland holder for 5 x Pg11, for insertion in plug-in baseAGK65
Cable holder, for insertion in plug-in base and introduction of cableAGK66
Spacer (empty casing), to increase the overall height of LOA...-AGK21
types to LAB / LAI height
Adapter, for replacing LAB1 / LAI... by LOA...KF8819
(rewiring of plug-in base not required)
Service adapter, with signal lamps for making a functional checkKF8833
and with jacks for making detector current measurements
Remote reset module for use with LOA26... / LOA36...ARK21A27
(printed circuit board)
2)
2)
2)
2)
2)
LOA3...
AGK12
AGK 4 408 5625 0
AGK 4 408 5626 0
KF8883
KF8884
Landis & StaefaCC1N7118EDecember 10, 19971/13
1)
For safety reasons (self-test of flame supervision circuit, etc.), at least one controlled shutdown
must take place every 24 hours
2)
On request only
Page 2
The type references given in the table apply to burner controls without base and without
Standard
Standard
With remote
For flash-steam
For incinerator
Type summary
flame detector.
VersionVoltage
(VAC)
Type referenceUnder-
voltage
CE
detection
Without bridging contact for the release contact of the oil pre-heater
LOA25... and LOA28... can only be used with photo-resistive detectors QRB1...
Since LOA25... and LOA28... do not feature extraneous light lockout, they do not conform to EN 230
2)
It is also possible to use an infrared flicker detector IRD1010 (refer to data sheet 7120)
3)
Since LOA21... and LOA22... do not feature undervoltage detection, they do not conform to EN 230
twHeating up time of «OH» until contact «OW»
delivers a signal
t2Safety timet3Pre-ignition time
t3nLong post-ignition timet3n’Short post-ignition time
t4Interval from establishment of flame to release
of the 2nd fuel valve
Burner control output signals
Required input signals
A’Beginning of startup sequence with burners
using an oil pre-heater «OH»
ABeginning of startup sequence with burners
using no oil pre-heater
BTime of flame establishmentOHOil pre-heater
CRunning positionOWRelease contact of «OH»
DControlled shutdown by «R»QRBPhoto-resistive detector
ALAlarm device
BVFuel valveRControl thermostat or pressurestat
EK1Lockout reset buttonSAActuator with automatic setback
EK2Remote lockout reset buttonSiExternal pre-fuse
FRFlame relayTZThermal-electric sequence switch
fr**Bridging contact for release contact of «OH»tz...Contacts of «TZ»
FSFlame signalVFlame signal amplifier
LED1Indication of flame strength (green)WLimit thermostat or pressure monitor
L1Indication of faults (red)ZIgnition transformer
L2Indication of operation (orange)
t1Pre-purge time
MBurner motor
Catch of flame relay for locking contact
K
«tz1» in the case of premature flame
signals or for locking this contact when
flame signal is correct
Whenever a fault occurs, the supply of fuel is immediately interrupted.
Control sequence in
the event of faults
Indications
With every lockout, the control outputs will be de-energized in less than one second,
while terminal 10 (AL) for the remote indication of lockout receives voltage.
The LOA… can be reset no earlier than 50 seconds after lockout.
Extraneous light /
premature flame signal
Non-appearance of
flame
During the pre-purge time, no flame signal may be present.
If, however, a signal is delivered during this period of time, the LOA… locks out on expiry
of the pre-purge and safety time. Under these circumstances, the oil valve does not
open.
An erroneous flame signal can be caused, for instance, by
– premature establishment of flame due to a leaking oil valve
– extraneous light
– a short-circuit in the detector or its wiring
– faults in the flame signal amplifier, or similar
Exception: with the LOA25… and LOA28…, there will be no lockout, but burner startup
will be prevented until the premature flame signal is no longer present.
This means that LOA25… and LOA28… may be used only where the requirements of
EN 230 need not be met.
If, at the end of the safety time, there is no flame signal, the LOA… will immediately
lock out.
If, with the LOA25… and LOA28…, there are flame signal failures of short duration
during the safety time «t2» and the interval «t4», the ignition transformer will immediately
be switched on again.
The total duration of the repeated ignition attempts equals the safety time «t2»
(10 seconds).
Flame failure during
operation
Undervoltage detection
Fault position
Flame strength
Operation
On flame failure during operation, the LOA… will immediately shut down the fuel
supply and automatically recycle (restart attempts).
If flame failure occurs on completion of «t4», almost the complete startup sequence
will be restarted.
With burner controls featuring undervoltage detection, an additional electronic circuit
ensures that in the event of mains voltages below about 165 V, burner startup will be
prevented, or - without opening the oil valve - the burner control locks out.
The fault position is indicated by the lamp integrated in the reset button.
Only with the LOA36...
The green LED for indication of the flame strength is used for checking the flame signal.
To ensure reliable burner operation, this LED must be lit.
If, during burner operation, the green LED flickers or extinguishes, the light conditions at
the burner are inadequate, caused by dirt, for instance.
Only with the LOA36...
Landis & StaefaCC1N7118EDecember 10, 19977/13
If the contact of the control thermostat «R» is closed, the orange LED is lit, thus indicating
the start of the oil pre-heater's heating up phase (if fitted).
Non-observance of the following safety notes may lead to
unforeseen detrimental consequences, such as electric shock,
explosion, environmental damage, etc.
• In the geographical areas where DIN standards are in use, the
installation must be in compliance with VDE requirements, particularly
with the standards DIN / VDE 0100 and 0722!
In all other areas in compliance with the national and local standards
and regulations.
• All regulations and standards applicable to the particular application
must be observed!
• Installation and commissioning work must always be carried out by
qualified personnel!
• Ignition cables must always be laid separately, maintaining the greatest
possible distance to the unit and other cables!
• Observe the notes on the laying of detector cables (refer to «Flame
detectors»)!
Accessories
• Check wiring carefully before putting the burner control into operation!
• LOA... are safety devices. It is therefore not permitted to open, interfere
with or modify the units!
• The LOA... must be completely isolated from the mains before
performing any work on it!
• Check all safety functions when putting the burner control into
operation or after performing service work!
• Ensure protection against electric shock on the unit itself and on all
electrical connections through appropriate mounting!
• Electromagnetic emissions must be checked from an application point
of view!
• Always press reset button manually without using any tools or sharp-
Plug-in base with screw terminals. Hatched: position ofPlug-in base for clip connections. Hatched: position of
insertable cable gland holder or cable holderinsertable cable gland holder or cable holder
«B»: holes for cable entry«B»: holes for cable entry from below
«31», «32»: auxiliary terminals. «N»: neutral terminals,Connection choices:
connected to neutral input (terminal 2)1, 3 and 4 each max. 4 clips Earthing: total of 6 clips,
Bottom: 4 earth terminals, joining a lug2max. 8 clips connected to lug «C»
for earthing the burner5 through 10 eachmax. 3 clips for earthing the burner
11, 12 eachmax. 4 clips
31, 32 eachmax. 2 clips
The two narrow sides of the base are provided with catches which engage in the casing when the
latter is plugged in. To disengage the catches, a screwdriver must be slightly tilted in the appropriate
guiding slots.
Mandatory ( AGK11 and AGK12 ): connection of earthing lug «C» and of fixing screws in «A»
to the ground of the burner (using a metric screw with lockwasher or similar).
ARK21A27
Remote reset module for use with LOA26... / LOA36...
(printed circuit board with no housing).
Degree of protection IP00, that is, protection against
electric shock hazard must be ensured through
mounting.
Do not place any metal objects in the hatched area.
The module must be fitted with the help of spacers
made of plastic. Do not use spacers made of metal!