Siemens LFL1.133 User manual

CC1N7451en
20.11.2017
Building Technologies Division
7451
Burner Controls LFL1...
Burner controls
For gas, oil or dual-fuel forced draft burners of medium to high capacity
For multistage or modulating burners in intermittent operation
With checked air damper control
Flame supervision
– with UV detectors QRA2 / QRA4 / QRA10
– and ionization probe
The LFL1... and this Data Sheet are intended for use by OEMs which integrate the
burner controls in their products!
Use
Control and supervision of forced draft burners of direct spark flame or interrupted
pilot construction
For medium to high capacity
For intermittent operation (at least one controlled shutdown every 24 hours)
For universal use with multistage or modulating burners
For use with stationary air heaters (WLE)
For use with dual-fuel burners
Type-tested and approved in accordance with DIN EN 298
The flame supervision is ensured via a flame detector QRA2 / QRA4 / QRA10 or
ionization probe. The difference between 01 series and 02 series is the duration of the
safety time for the pilot burner of burners equipped with pilot gas valves.
For atmospheric burners of high capacity, use the LFL1.638.

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Supplementary documentation
Product type Type of documentation Documentation number
LGK16 (burner controls for continuous
operation)
Data Sheet N7785
Warning notes
To avoid injury to persons, damage to property or the environment, the following
warning notes must be observed!
Do not open, interfere with or modify the unit!
All activities (mounting, installation and service work, etc.) must be performed by
qualified staff
Before making any wiring changes in the connection area, completely isolate the
plant from mains supply (all-polar disconnection). Ensure that the plant cannot be
inadvertently switched on again and that it is indeed dead. If not observed, there is
a risk of electric shock hazard
Ensure protection against electric shock hazard by providing adequate protection
for the burner control’s connection terminals
Each time work has been carried out (mounting, installation, service work, etc.),
check to ensure that wiring is in an orderly state and make the safety checks as
described in «Commissioning notes»
Press the lockout reset button only manually (apply a force of no more than 10 N),
without using any tools or pointed objects
Do not press the lockout reset button on the unit or the remote lockout reset button
(input 21)for more than 10 seconds since this damages the lockout relay in the unit
Fall or shock can adversely affect the safety functions. Such units must not be put
into operation, even if they do not exhibit any damage
For safety reasons – self-test of the flame supervision circuit, etc. – at least one
controlled shutdown must take place every 24 hours
In the case of flame supervision with UV detectors QRA2 / QRA4 / QRA10, it
should be noted that sources of radiation such as halogen lamps, welding
equipment, special lamps, ignition sparks, as well as X-rays and gamma radiation,
can produce erroneous flame signals
Mounting notes
Ensure that the relevant national safety regulations are complied with
Connect the earthing lug inside the terminal base to burner ground using a screw
with a lockwasher
An ignited UV tube is a source of UV radiation! In case of flame supervision by
means of flame detectors, the detectors must be placed such that there is no
direct visual contact between them. If this is not observed, there is a risk of loss
of safety functions
Installation notes
Always run the high-voltage ignition cables separately while observing the greatest
possible distance to the unit and to other cables
Do not mix up live and neutral conductors
Install switches, fuses and grounding in accordance with local regulations
Do not exceed the maximum permissible current rating of the connection terminals
The insulation of internal wiring which is subjected to the mains voltage must be
able to withstand the electrical loads occurring during proper use

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Application notes
For use in applications in dual-fuel burners or oil burners, the oil supply must be equipped with two shutoff valves connected in series.
Observe the following:
EN 298:2012, Section 7.101.3.3 Prepurge time for oil burner control systems and the
corresponding application standards.
Electrical connection of flame detectors
It is important to achieve practically disturbance- and loss-free signal transmission:
Never run the detector cable together with other cables
– Line capacitance reduces the magnitude of the flame signal
– Use a separate cable
Observe the maximum permissible detector cable lengths (refer to «Technical data»)
2 UV detectors QRA2 / QRA4 / QRA10 can be connected in parallel (observe the
warning note)
In connection with the QRA2 / QRA4 / QRA10, earthing of terminal 22 is mandatory
The ionization probe is not protected against electric shock hazard
Locate the ignition electrode and the ionization probe so that the ignition spark
cannot arc over to the ionization probe (risk of electrical overloads) and that the
ignition sparks cannot adversely affect the supervision of ionization
Supervision with both ionization probe and UV detector QRA2 / QRA4 / QRA10 is
possible, but for safety reasons – with the exception of the second safety time «t9»
– only 1 flame detector may be active at a time. At the end of the second safety
time, 1 of the detectors must be inactive, however, that is, the detected flame must
have extinguished, e.g. by switching off the ignition valve via terminal 17
Commissioning notes
When commissioning the plant or when doing maintenance work, make the following
safety checks:
Safety check to be carried out Anticipated response
a) Burner start with flame detector darkened Lockout at the end of «TSA»
b) Burner start with flame detector exposed to
extraneous light
Lockout after no more than 40
seconds
c) Burner operation with simulated loss of
flame; for that purpose, darken the flame
detector in operation and maintain that state
(not possible with ionization)
Lockout
d) Burner startup with response from air
pressure switch interruption
Start prevention / lockout during
the prepurge time
e) Burner operation with air pressure failure
simulation
Immediate lockout

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Engineering notes
Install switches, fuses, earthing, etc., in compliance with local regulations
Decisive for the connection of the valves and other plant components is the plant
diagram provided by the burner manufacturer
34 5 6 7
+
22 23 24
ION
12
BV2
va
M
zm
QRA...
ZBV
BV1 BV2
BV1
LK
SA
LR
BV3
R
d1
N
M1
d2
N
M2 Z
N
1
EK2
AL
bv...
LP
GP
W
11 10 822
23 24
H
L
67
16 17 18 19 20 9
221 313 12 14 45
(1)/(3)
7451a14e/0604
TSA´, t3´, t4´, only:
LFL1.335,
LFL1.635 and
LFL1.638
SB
Si
Connect safety limit thermostat in the line (manual reset, e.g. «SB»)
Remote reset
When remote reset button «EK2» is connected between terminal 21 and
- terminal 3, only remote reset is possible
- terminal 1, both remote emergency shutdown and remote reset are possible
Required switching capacities
- of the switching devices connected between terminals 12 and 4 (refer to «Technical data»)
- of the switching devices connected between terminals 4 and 14 (refer to «Technical data»)
- depending on the loads applied to terminals 16...19 (refer to «Technical data»)
Air pressure supervision
If the air pressure is not monitored with air pressure switch «LP», terminal 4 must be connected to terminal 12, and terminal 6
to terminal 14. Terminal 13 is not used.
Control contacts of the other devices in the burner installation – if series-connected – are to be connected as follows:
- To terminal 4 or 5 contacts which must be closed from startup to controlled shutdown otherwise no start or shutdown
- To terminal 12 contacts which must only be closed on startup otherwise no start
- To terminal 14 contacts which must be closed at the beginning of the preignition time at the latest, and which must stay
closed until controlled shutdown occurs
For use in oil applications, the oil supply must be equipped with two shutoff valves connected in
series.
Observe the following:
EN 298:2012, Section 7.101.3.3 Prepurge time for oil burner control systems and the corresponding
application standards.
Connection of fuel valves with direct spark flame burners. With 2-stage burners, «BV2» is connected in place of «BV3»
 Connection of fuel valves with interrupted pilot burners
Direct connection of a fuel valve to terminal 20 is only permitted
-in plants with a main shutoff valve on the mains side (safety shutoff valve), which is controlled by terminal 18 or 19, and
-if 2-stage valves are used, provided they fully close when the first stage, controlled by terminal 18 or 19, is switched off
For additional examples of air damper control, refer to «Connection examples». In the case of actuators with no end switch
«z» for the fully CLOSED position of the air damper, terminal 11 must be connected to terminal 10 otherwise no burner
start.
Simultaneous use of ionization and UV supervision is possible
For the permissible length and laying of detector cables, see Flame supervision

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Standards and certificates
Applied directives:
Low-voltage directive 2014/35/EC
Directive for gas-fired appliances 2009/142/EC
Electromagnetic compatibility EMC (immunity) *) 2014/30/EC
Directive for pressure devices Valid until 2018-04-21:
2009/142/EG
Gas Appliances Regulation (EU) Valid from 2018-04-21:
(EU) 2016/426
*) The compliance with EMC emission requirements must be checked after the burner control is
installed in equipment
Compliance with the regulations of the applied directives is verified by the adherence to
the following standards / regulations:
Automatic burner control systems for burners and
appliances burning gaseous or liquid fuels
DIN EN 298
Safety and control devices for gas burners and gas burning
appliances
DIN EN 13611
Automatic electrical controls for household and similar use
Part 2-5: Particular requirements for automatic electrical
burner control systems
DIN EN 60730-2-5
The relevant valid edition of the standards can be found in the declaration of
conformity!
Note on DIN EN 60335-2-102
Household and similar electrical appliances - Safety - Part 2-102:
Particular requirements for gas, oil and solid-fuel burning appliances having electrical
connections. The electrical connections of the LFL and the AGM comply with the
requirements of EN 60335-2-102.
EAC Conformity mark (Eurasian Conformity mark)
ISO 9001:2015
ISO 14001:2015
OHSAS 18001:2007
China RoHS
Hazardous substances table:
http://www.siemens.com/download?A6V10883536
Certified complete with plug-in base and flame detector:
Type
reference
LFL1.122 ●--- ●●●●●●
LFL1.133 ●--- ●●--- ●--- ●
LFL1.322 ●--- ●●●●●●
LFL1.333 ●--- ●●●●--- ●
LFL1.335 ●●●●●●●●
LFL1.622 ●--- ●●●●●●
LFL1.635 ●--- ●●●●●●
LFL1.638 --- --- ●--- --- ●--- ●

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Life cycle
Burner controls has a designed lifetime* of 250,000 burner startup cycles which, under
normal operating conditions in heating mode, correspond to approx. 10 years of usage
(starting from the production date given on the type field).
This lifetime is based on the endurance tests in the standard EN 298.
A summary of the conditions has been published by the European Control
Manufacturers Association (Afecor) (www.afecor.org).
The designed lifetime is based on use of the burner controls according to the
manufacturer’s Data Sheet. After reaching the designed lifetime in terms of the number
of burner startup cycles, or the respective time of usage, the burner control is to be
replaced by authorized personnel.
* The designed lifetime is not the warranty time specified in the Terms of Delivery
Disposal notes
The unit contains electrical and electronic components and must not be disposed of
together with domestic waste.
Local and currently valid legislation must be observed.
Mechanical design
-Plug-in design
-Exchangeable unit fuse (including spare fuse)
-Made of impact-proof and heat-resistant black plastic
-Lockout reset button with viewing window showing
– the fault signal lamp
– the lockout indicator
- coupled to the program spindle
- visible in the transparent lockout reset button
-uses easy-to-remember symbols to indicate the type of fault and the time it
occurred
LFL1...
Housing

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Type summary
The type references given below apply to the LFL without plug-in base and without
flame detector. For ordering information for plug-in bases and other accessories, see
Accessories.
Switching times are given in seconds, in the burner startup sequence, valid for 50 Hz
mains frequency. At 60 Hz, switching times are about 17 % shorter.
The type references apply to burner controls operating on AC 230 V, 50...60 Hz.
Flash steam
generators Flash steam generators Incl. stationary
air heaters
²) Large
atmospheric
burners
Type LFL1.122 ¹)
02 series
LFL1.133 ¹)
02 series
LFL1.322 ¹)
02 series
LFL1.333 ¹)
02 series
LFL1.335 ¹)
01 series
LFL1.622 ¹)
02 series
LFL1.635 ¹)
01 series
LFL1.638
01 series
Article
no.
BPZ:LFL1.122 BPZ:LFL1.133 BPZ:LFL1.322 BPZ:LFL1.333 BPZ:LFL1.335 BPZ:LFL1.622 BPZ:LFL1.635 BPZ:LFL1.638
Times in seconds (s)
t1 10 9 36 31 37 65 66 66
TSA 2 3 2 3 2.5 22.5 2.5
TSA´ 2 3 2 3 5 2 5 5
t3 4 3 4 6 5 4 5 5
t3´ 4 --- 4 6 2.5 4 2.5 2.5
t4 6 6 10 11.5 12.5 10 12.5 12.5
t4´ 6 --- 10 11.5 15 10 15 15
t5 4 3 10 11.5 12.5 10 12.5 12.5
t6 10 14.5 12 18 15 12 15 15
t7 2 3 2 3 2.5 2 2.5 2.5
t8 30 29 65 69 74 95 103 103
t9 2 3 2 3 5 2 5 7.5
t10 6 6 811.5 10 810 10
t11 Optional
t12 Optional
t13 10 14.5 12 17 15 12 15 15
t16 4 3 4 6 5 4 5 5
t20 32 60 --- 26 22 --- --- ---
¹) Available as AC 100...110 V versions; add type suffix «-110 V» when ordering
²) Reversed polarity protection conforming to Dutch installation standard: AGM30
Legend of times
TSA Ignition safety time t8 Duration of startup sequence (without «t11» and «t12»)
TSA‘ Ignition safety time or first safety time t9 Second safety time with burners using pilot burners
(startup with burners using pilot burners) t10 Interval from start to the beginning of the air pressure
t1 Prepurge time with air damper open check, excluding running time of air damper
t3 Preignition time t11 Air damper running time to the OPEN position
t3‘ Preignition time (long) t12 Air damper running time to the low-fire position MIN
t4 Interval between voltage at terminals 18 and 19 t13 Permissible afterburn time
t4‘ Interval between start of TSA´ and release of valve at t16 Interval until OPEN command for the air damper is given
terminal 19 t20 Interval to the self-shutdown of the sequence switch
t5 Interval between power at terminals 19 and 20 after startup
t6 Postpurge time (with «M2»)
t7 Interval between start command and power at terminal 7
(start delay for «M2»)

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Accessories (to be ordered separately)
Flame detectors UV flame detectors QRA2...
See Data Sheet N7712
UV flame detector QRA4...
See Data Sheet N7711
UV flame detector QRA10...
See Data Sheet N7712
Ionization probe
to be supplied by thirds
Connection accessories
for medium-capacity
burner controls
Plug-in base AGM410490550 with Pg11 thread for cable
entry glands.
Article no.: BPZ:AGM410490550
See Data Sheet N7230
Plug-in base AGM14.1 with M16 thread for cable entry
glands.
Article no.: BPZ:AGM14.1
See Data Sheet N7230
Others Reversed polarity protection AGM30 for Netherlands
Article no.: BPZ:AGM30

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Accessories (to be ordered separately)
Actuators Actuator SQN72...
See Data Sheet N7802
Actuator SQN70... / SQN71... / SQN74... / SQN75...
See Data Sheet N7804
Actuator SQN9...
See Data Sheet N7806
Actuator SQM40... / SQM41
See Data Sheet N7817
Actuator SQM5...
See Data Sheet N7815

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Technical data
Mains voltage
A
C 230 V –15 / +10 %
A
C 100 V –15%...AC 110 V +10%
Mains frequency 50...60 Hz ±6 %
Unit fuse (built-in) T6.3H250V to DIN EN 60 127
Primary fuse (external) max. 10 A (slow)
Weight approx. 1,000 g
Power consumption approx. AC 3.5 VA
Mounting position optional
Degree of protection IP 40, when built in, with the exception of
the connection area (terminal base)
Safety class II
Perm. input current at terminal 1 max. 5 A continuously (peaks 20 A / 20 ms)
Perm. load on control terminals 3, 6, 7,
9...11, 15...20
max. 4 A continuously (peaks 20 A / 20 ms)
Required switching capacity of switching
devices
-Between terminals 4 and 5
-Between terminals 4 and 12
-Between terminals 4 and 14
1 A, AC 250 V
1 A, AC 250 V
min. 1 A, AC 250 V
depending on the load on terminals 16...19
Permissible length of the standard detector
cable (laid separately)
See Technical Data, chapter Flame
supervision
Capacity
-Output on startup (without fan
assistance)
-Nominal output
Optional (with ignition <120 kW)
Optional
Storage DIN EN 60721-3-1
Climatic conditions class 1K3
Mechanical conditions class 1M2
Temperature range -20...+60 °C
Humidity < 95 % r.h.
Transport DIN EN 60721-3-2
Climatic conditions class 2K3
Mechanical conditions class 2M2
Temperature range -20...+60 °C
Humidity < 95 % r.h.
Operation DIN EN 60 721-3-3
Climatic conditions class 3K3
Mechanical conditions class 3M3
Temperature range -20...+60 °C
Humidity < 95 % r.h.
Installation altitude Max. 2,000 m above sea level
Warning!
Condensation, formation of ice and ingress of water are not permitted!
If not observed, there is a risk of impairment of safety functions and of
electric shock hazard.
General unit data
LFL1...
Environmental
conditions

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Technical data (cont'd)
Voltage at the ionization probe
- Operation
- Test
A
C 330 V ±10 %
A
C 380 V ±10 %
Short-circuit current max. 0.5 mA
Recommended range of measuring
instrument
0...50 µA
Perm. length of detector cable
- Normal cable, laid separately ²)
- Shielded cable
max. 80 m
max. 140 m (e.g. high-frequency cable;
shielding connected to terminal 22)
Required detector current in operation min. 6 µA
Possible detector current in operation max. 200 µA
Supply voltage
- Operation
- Test
A
C 330 V ±10 %
A
C 380 V ±10 %
Required detector current min. 70 µA
Possible detector current
- Operation
- Test
max. 700 µA
max. 1000 µA ¹)
Perm. length of detector cable
- Normal cable, laid separately ²)
- Shielded cable
max. 100 m
max. 200 m (e.g. high-frequency cable;
shielding connected to terminal 22)
¹) During the prepurge time with higher test voltage: Self-ignition and extraneous light test
²) Multicore cable not permitted
Detector current measurement
Ionization probe Flame detector QRA2 / QRA4 / QRA10
LFL1... 24
7451v01/0204
M
C
+
+-
ION
7451v02/0204
AM
C
23 22 LFL1...
-
+
-
+
QRA...
For detector currents, refer to «Technical data».
C Electrolytic condenser 100...470 µF; DC 10...25 V
ION Ionization probe
M Microammeter Ri max. 5,000 
Flame supervision with
ionization probe
Flame supervision with
flame detector QRA2 /
QRA4 / QRA10
Measuring circuit for
detector current
measurement
Legend

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Function
2-stage direct spark flame burner
min.
0...
100%
R
M1
M2
Z
BV1
LR
BV2
FS
ABCD
7451a06/0600
TP
M
R
M
LK
~
t7 t1 t6
t3
TSA
t4 t5
t11 t12 t13
Modulating direct spark flame burner
RLR
t5t11 t12
t13
FS
min.
LK
0...
M100%
RV
A
BV1
M2
Z
~
M
PR
M1
T
t4
t3
t7 t1
TSA
B
t6
CD
7451a07/0600
2-stage interrupted pilot burner
FS
BV2
min.
LK 0...
M
R
100%
LR
ZBV
M1
M2
Z
~
M
PR
T
t12
t4´
t5
ABCD
t11 t13
t6
t7 t1
t3´
TSA´
7451a08/0202
t9
BV1
Legend
BV... Fuel valve
FS Flame signal amplifier
LK Air damper
LR Load controller
M... Fan or burner motor
R Control thermostat or pressurestat
RV Modulating fuel valve
Z Ignition transformer
ZBV Pilot gas valve
A Start command by «R»
B Operating position of burner
B-C Burner operation
C Controlled shutdown
C-D Sequence switch travels to start position
«A», postpurging
D-A End of control sequence
t1 Prepurge time with air damper fully open
t3/t3´ Preignition time
t4/t4´ Interval «BV1-BV2» or «BV1-LR»
t5 Interval between voltage at terminal
19 and terminal 20
t6 Postpurge time
t7 Interval between start command and
voltage at terminal 7
t9 2nd safety time with burners equipped
with a pilot burner
t11 Air damper’s running time to the fully
OPEN position
t12 Air damper’s running time to the low-fire
position
t13 Permissible afterburn time
TSA/
TSA´ Ignition safety time

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Function (cont'd)
The following features enable the LFL1... to offer a high level of additional safety:
-Detector and extraneous light test are resumed immediately on completion of the
afterburn time «t13». Fuel valves that are not closed, or not fully closed,
immediately initiate lockout on completion of the afterburn time «t13». The test will
only be terminated when the prepurge time «t1» of the next startup sequence has
elapsed.
-The proper functioning of the flame supervision circuit is automatically checked
during each startup phase of the burner.
-During the postpurge time «t6», the control contacts for the release of fuel are
checked to ensure they have not welded.
-The built-in unit fuse protects the control contacts against overloads.
-Burner operation with or without postpurging
-Fan motors with a current draw of up to 4 A can be connected directly starting
current max. 20 A (max. 20 ms)
-Separate control outputs for one pilot valve, which will be shut on completion of the
second safety time
-Separate control outputs for the actuator’s positioning directions «OPEN»,
«CLOSE» and «MIN»
-Checked air damper control to ensure prepurging with the nominal amount of air
-Checked positions:
- «CLOSED» or «MIN» on startup low-fire position
- «OPEN» at the start of prepurging
- «MIN» on completion of prepurging
If the actuator does not drive the air damper to the required position, the burner
startup sequence will be stopped
-2 control outputs for the release of the second and third output stage, or load control
-When load control is enabled, the control outputs for the actuator will galvanically
be separated from the unit’s control section
-Connection facilities for
- remote lockout warning device
- remote reset
- remote emergency shutdown
-With burner controls of the 01 series and direct spark flame burners, the safety time
can be increased from 2.5 to 5 seconds by changing the circuitry (refer to
«Connection examples»), provided the longer safety time conforms to local safety
regulations
-With the ionization probe, in networks with earthed or nonearthed neutral
conductor. For this kind of supervision, the flame supervision circuit is designed
such that possible disturbances of the ionization current due to the ignition spark
normally have no impact on the establishment of the flame signal. A short-circuit
between ionization probe and burner ground causes loss of the flame signal
-With UV detector QRA2 / QRA4 / QRA10 (gas and oil burners)
-Simultaneous use of ionization probe and UV detector QRA2 / QRA4 / QRA10 (e.g.
with interrupted pilot burners or gas-electrically ignited oil burners)
-If, on startup, the required input signals are not present, the burner control
interrupts the startup sequence at the points marked by symbols and initiates
lockout where required by safety regulations. The symbols used in this Data Sheet
correspond to those on the burner control’s lockout indicator.
General
Control of the burner
Flame supervision
Preconditions for
startup

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Function (cont'd)
-Burner control must be reset
-Sequence switch must be in its start position voltage at terminals 4 and 11 present
-Air damper closed
-End switch «z» for the «CLOSED» position must feed voltage from terminal 11 to
terminal 8
-The contacts of control thermostat or pressurestat «W» and other contacts of
switching devices connected between terminal 12 and «LP» must be closed e.g.
control contact for the oil preheater’s temperature
-Terminal 4 must be live
-The N.C. contact of the air pressure switch must be closed «LP» test
Preconditions for burner
startup

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Startup sequence
A Start command delivered by «R»
«R» closes the start control loop between terminals 4 and 5
-The sequence switch starts running
- Only prepurging, power is immediately fed to the fan motor connected to terminal 6
- Pre- and postpurging; on completion of «t7», power is fed to the fan motor or flue gas fan connected
to terminal 7
-On completion of «t16», the control command to open the air damper is delivered via terminal 9
-No power is fed to terminal 8 during the positioning time
-The sequence switch continues its travel only after the air damper has fully opened
t1 Prepurge time with air damper fully open
-During «t1», the correct functioning of the flame supervision circuit is tested
-If test is not successful, the burner control will initiate lockout
Shortly after the start of «t1», the air pressure switch must change over from terminal 13 to terminal 14.
Otherwise lockout
Start of air pressure check
At the same time, terminal 14 must be live since the ignition transformer will be powered and the fuel
released via this current path.
On completion of the prepurge time, the burner control will drive the air damper to the low-fire position via
terminal 10, which is determined by the changeover point of auxiliary switch «m». During the positioning
time, the sequence switch stops again. A short time later, the motor of the sequence switch will be switched
to the control section of the burner control. This means that, from now on, positioning signals delivered to
terminal 8 have no impact on the burner’s further startup sequence (and on subsequent burner operation):
t5 Interval
-On completion of «t5», power is fed to terminal 20; at the same time, control outputs 9...11 and input 8
are galvanically separated from the unit’s control section
The LFL1... is now protected against return voltages from the power control loop
-The startup sequence of the LFL1… ends with the release of «LR» at terminal 20
-After a number of idle steps (steps with no change of the contact position), the sequence switch
switches itself off
Direct spark flame burners
TSA Ignition safety time
On completion of «TSA», a flame signal must be present at terminal 22. It must not be interrupted until
controlled shutdown takes place otherwise lockout
t3 Preignition time
Release of fuel via terminal 18
t4 Interval «BV1 – BV2» or «BV1 - LR»
-On completion of «t4», terminal 19 is live
-That powers «BV2» connected to the actuator’s auxiliary switch «v»

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Startup sequence (cont'd)
Interrupted pilot burners
t3
t3´ Preignition time
Release of fuel for pilot burner via terminal 17
TSA
TSA´ Ignition safety time
On completion of «TSA», a flame signal must be present at terminal 22. It must not be interrupted until
controlled shutdown takes place
otherwise non-volatile lockout
t4
t4´ Interval «ZBV-BV1»
Up to the release of the fuel valve at terminal 19 for the main burner’s start load
t9 Second safety time
On completion of the second safety time, the main burner must have been ignited by the pilot burner since
terminal 17 becomes dead as soon as this time has elapsed, causing the pilot valve to close
B Operating position of the burner
B-C Burner operation
-During burner operation, «LR» drives the air damper to the high-fire or low-fire position, depending on
the demand for heat
-Release of high-fire is enabled by auxiliary switch «v» in the actuator
-In the event of loss of flame during operation, the LFL1… will initiate lockout
C Controlled shutdown
On controlled shutdown, the «BV...» will immediately be closed. At the same time, the sequence switch
starts and programs «t6»
C-D The sequence switch travels to start position «A», postpurging
When burner off time starts, control terminals 11 and 12 carry voltage to drive the air damper to the fully
CLOSED position. Flame signal supervision also remains active during burner off times
t6 Postpurge time
-Fan «M2» connected to terminal 7
-Shortly after the start of «t6», power is fed to terminal 10
air damper will be driven to the MIN position
-Full closing of the air damper starts only shortly before «t6» has elapsed
triggered by the control signal at terminal 11
-During the following burner off period, terminal 11 remains live
t13 Permissible afterburn time
During «t13», the flame signal input can still receive a flame signal
no lockout
D-A End of control sequence
start position
As soon as the sequence switch has reached the start position – thereby switching itself off – the flame
detector and extraneous light test will start again.
During burner off periods, the flame supervision circuit is live. A faulty flame signal of a few seconds will
initiate lockout.
Short ignition pulses of the UV tube, caused for instance by cosmic radiation, do not lead to lockout.
Times «TSA´», «t3´» and «t4´» only exist with burner controls of the 01 series.

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Control sequence under fault conditions and lockout indication
In case of any faults, the fuel supply is always interrupted immediately. In the event of
any kind of fault, the sequence switch will stop and, with it, the lockout indicator.
The symbol above the indicator’s reading mark gives the type of fault:
No start One of the contacts is not closed (also refer to «Preconditions for burner startup»)
Extraneous light
Lockout during or after completion of the control sequence.
Examples:
– Flames that have not extinguished
– Leaking fuel valves
– Defect in the flame supervision circuit
=Startup
interruption
Terminal 8 has not received the OPEN signal from end switch «a»
Terminals 6, 7 and 14 remain live until the fault has been corrected
P Lockout No indication of air pressure at the beginning of the air pressure check
Loss of air pressure after the air pressure check
Lockout Defect in the flame supervision circuit
>Startup
interruption
Terminal 8 has not received the positioning signal from auxiliary switch «m» for the
low-fire position
Terminals 6, 7 and 14 remain live until the fault has been corrected
1 Lockout No flame signal on completion of safety time «TSA»
2 Lockout No flame signal on completion of the second safety time (flame signal of main flame
with interrupted pilot burners)
I Lockout Loss of flame signal during operation
After the reset, the burner control sequence switch first returns to the start position and
then initiates a burner restart. If lockout occurs any other moment in time between start
and preignition not indicated by a symbol, the usual cause is a premature flame signal,
that is, a faulty flame signal, caused for instance by a self-igniting UV tube.
a-b Startup sequence
b-b´ Idle steps
(with no contact confirmation)
b (b´)-a Postpurge program
Duration of safety time with
direct spark flame burners
 Duration of safety times with
interrupted pilot burners
LFL1... Series 01 LFL1... Series 02
When lockout has occurred, the burner control can immediately be reset.
– Do not press the lockout reset button for more than 10 seconds
The sequence switch always returns to its start position first
– After resetting
– After correction of a fault which resulted in plant shutdown
– After each power failure
During that period of time, power is only fed to terminals 7 and 9...11.
The burner control then carries out a burner restart
Note!
Do not press the lockout reset button for more than 10 seconds.
Lockout indicator

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Connection diagrams (for circuit variants, refer to «Connection examples»)
34 5 6 7
+
22 23 24
ION
12
BV2
va
M
zm
QRA...
ZBV
BV1 BV2
BV1
LK
SA
LR
BV3
R
d1
N
M1
d2
N
M2 Z
N
1
EK2
AL
bv...
LP
GP
W
11 10 822 23 24
H
L
67
16 17 18 19 20 9
221 313 12 14 45
t11
t12
t5
t1
1
2
t13
(1)/(3)
t3
TSA
t4
t5
zma
t16
D
A
t7
t6
t3´
TSA´
t4´
t9
AS
A
t10
P
B
C
7451a02e/0604
TSA´, t3´, t4´, only:
LFL1.335,
LFL1.635 and
LFL1.638
SB
Si
Attention!
Do not press lockout reset button «EK...» for more than 10 seconds!
For the connection of the safety shutoff valve, refer to the plant diagram
provided by the burner manufacturer.

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Connection diagram (for circuit variants, refer to «Connection examples»)
1
AS
br1
ar1 IXV
ar2
ION
22 23 24
76
12
4
R
LP
513 14
N
M1 M2
d1 d2
22 23 24
QRA...
fr1
XI XIII XII
AR
br2
L1
EK1
BR
321 216
AL
NH
EK2
(1)/(3)
17 19
Z
ZBV BV1
20 911 8
LK
SA azm
M
E
A
M
ab b
a
abba
ab
b
a
a
b
fr3
NTC
fr2 FR V
(1) (2)
ab
XIV
IV
X
II
bba
a
7451a12/0204
15
VIII
ba
18
VVI
ba
III
ba
b
aar3
ba
VII
10
M
SM
GP
v
BV1
BV2
BV2
LR
+
SB
L
H
W
Si
Attention!
Do not press lockout reset button «EK...» for more than 10 seconds!
For the connection of the safety shutoff valve, refer to the plant diagram
provided by the burner manufacturer.

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Switchgear sequence
A
t11
t7
t1 t12
BC D
t6
t20
t13t10
t16
t8
Positions of lockout indicator
Control output
at terminal:
P
20
7
19
8
9
9
10
I
II
III
IV
V
VI
VII
VIII
X
XI
XII
XIII
XIV
a
b
a
b
a
b
a
b
a
b
a
b
a
b
a
b
a
b
a
b
a
b
7451d01/0604
12
16
11
17
18
7
XV a
b
12
t3 t4
*t3´ *t4´ t9
TSA
*TSA´ t5
1 2
LFL
«TSA´», «t3´» and «t4´»:
These times only apply to burner controls of the 01 series (LFL1.335, LFL1.635, and
LFL1.638). They do not apply to burner controls of the 02 series since cams Xand VIII
of these types of LFL1… perform simultaneous switching actions.