Technical data sheet BF24
Spring-return actuator for fire and smoke
dampers 90° in ventilation and air-
conditioning systems
• Torque 18 Nm / 12 Nm
• Nominal voltage AC/DC 24 V
• Control Open/close
• Mechanical interface Form fit 12x12 mm,
non-continuous hollow shaft
Technical data
Electrical data Nominal voltage AC/DC 24 V
Nominal voltage frequency 50/60 Hz
Nominal voltage range AC 19.2...28.8 V / DC 21.6...28.8 V
Power consumption in operation 7W
Power consumption in rest position 2W
Power consumption for wire sizing 10 VA
Power consumption for wire sizing note Imax 8.3 A @ 5 ms
Auxiliary switch 2 x SPDT
Switching capacity auxiliary switch 1 mA...6 A (3 A inductive), DC 5 V...AC 250 V (II,
reinforced insulation)
Switching points auxiliary switch 5° / 80°
Connection supply / control Cable 1 m, 2 x 0.75 mm² (halogen-free)
Connection auxiliary switch Cable 1 m, 6 x 0.75 mm² (halogen-free)
Functional data Torque motor 18 Nm
Torque fail-safe 12 Nm
Direction of motion motor selectable by mounting L/R
Manual override with position stop
Angle of rotation Max. 95°
Running time motor <120 s / 90°
Running time fail-safe 16 s @ 20°C
Sound power level, motor 45 dB(A)
Sound power level, fail-safe 63 dB(A)
Mechanical interface Form fit 12x12 mm, non-continuous hollow
shaft
Position indication Mechanically, with pointer
Service life Min. 60'000 safety positions
Safety data Protection class IEC/EN III, Safety Extra-Low Voltage (SELV)
Protection class auxiliary switch IEC/EN II, reinforced insulation
Degree of protection IEC/EN IP54
IP protection in all mounting positions
EMC CE according to 2014/30/EU
Low voltage directive CE according to 2014/35/EU
Certification IEC/EN IEC/EN 60730-1 and IEC/EN 60730-2-14
Mode of operation Type 1.AA.B
Rated impulse voltage supply / control 0.8 kV
Pollution degree 3
Ambient humidity Max. 95% RH, non-condensing
Ambient temperature normal operation -30...50°C
Ambient temperature safety operation The safety position will be attained up to max.
75°C
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Technical data sheet BF24
Safety data Storage temperature -40...50°C [-40...122°F]
Servicing maintenance-free
Weight Weight 2.6 kg
Safety notes
• The device must not be used outside the specified field of application, especially not in aircraft
or in any other airborne means of transport.
• The actuator is adapted and installed on the fire and smoke damper by the damper
manufacturer. For this reason, the actuator is only supplied directly to safety damper
manufacturers. The manufacturer then bears full responsibility for the proper functioning of
the damper.
• The two switches integrated in the actuator are to be operated either on power supply voltage
or at safety extra-low voltage. The combination power supply voltage/safety extra-low voltage
is not permitted.
• The device may only be opened at the manufacturer's site. It does not contain any parts that
can be replaced or repaired by the user.
• The device contains electrical and electronic components and must not be disposed of as
household refuse. All locally valid regulations and requirements must be observed.
Product features
Mode of operation The actuator moves the damper to the operating position at the same time as tensioning the
return spring. The damper is turned back to the safety position by spring energy when the
supply voltage is interrupted.
Manual override Without power supply, the actuator can be operated manually and fixed in any required
position. It can be unlocked manually or automatically by applying the supply voltage.
Signalling Two microswitches with fixed settings are installed in the actuator for indicating the damper
end positions. The electrical contacts of these microswitches are equipped with a gold/silver
coating that permits integration both in circuits with low currents (mA range) and in ones with
larger-sized currents (A range) in accordance with the specifications in the data sheet. It should
be noted with this application however that the contacts can no longer be used in the
milliampere range after larger currents have been applied to them, even if this has taken place
only once.
The position of the damper blade can be read off on a mechanical position indication.
Standards / Regulations The design of the actuator is based on the specific requirements from the European standards:
- EN 15650 Ventilation for buildings – Fire dampers
- EN 1366-2 Fire resistance tests on service installations
(Part 2: Fire dampers)
- EN 13501-3 Fire classification of construction products and building elements
(Part 3: Classification using data from fire resistance tests on products and elements used in
building service installations: fire resisting ducts and fire dampers)
Recommendation for application The regular operational check (open/close control of the fire damper) enhances the safety of
people, animals, property and the environment. Unless other requirements are stipulated – e.g.
in the damper manufacturer's operating instructions – Belimo recommends the performance of
a monthly operational check. Fire damper actuators from Belimo are designed in accordance
with service life specifications contained in the technical data sheet for regular operational
checks. Notes for regular operational checks can be found in the European Product Standard for
Fire Dampers (EN 15650) under "Maintenance information".
Delivery notes Incl. Hand crank, Pointer, Protective bag, Form fit insert 12/10 mm
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Technical data sheet BF24
Accessories
Electrical accessories Description Type
Auxiliary switch 2 x SPDT SN2-C7
Thermoelectric tripping device with control key, Duct inside temperature BAT72
72°C (colour black), Duct outside temperature 72°C
Thermoelectric tripping device with control key, Duct inside temperature BAT72/9
72°C (colour black), Duct outside temperature 72°C
Cable set with plug 0.5 m for communication and power supply unit ZST-BS
Mechanical accessories Description Type
Bracket for SN2-C7 for BF ZSN-BF
Adapter, for form fit 12 mm on round shaft 18 mm, L = 33 mm ZA18-BF
Adapter, for form fit with clamp for round shaft 10...20 mm / square ZK-BF
10...16 mm
Pointer 12x12 mm ZZ12-B
Hand crank 40 mm ZK1-B
Hand crank 70 mm ZK2-B
Protective bag with wire, Multipack 100 pcs. ZSD-B.1
Electrical installation
Supply from isolating transformer.
Parallel connection of other actuators possible. Observe the performance data.
Wiring diagrams
AC/DC 24 V, open/close
Cable colours:
1 = black
2 = white
S1 = violet
S2 = red
S3 = white
S4 = orange
S5 = pink
S6 = grey
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Technical data sheet BF24
Dimensions
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