Pepperl+Fuchs LA28/LK28-FC-Z/31/116 Fire protection thru-beam sensor

Pepperl+Fuchs LA28/LK28-FC-Z/31/116 Fire protection thru-beam sensor

It is essential that fire is not allowed to spread in buildings should it break out. Fire protection regulations therefore prescribe fire barriers. These include fire doors, industrial fire doors and fire dampers, which are generally kept closed at all times. In areas where doors are left open, such as heavily traveled passageways and corridors, a selfclosing mechanism must be automatically triggered in case of fire.

Pepperl+Fuchs LA28/LK28-FC-Z/31/116 Fire protection thru-beam sensor
LA28/LK28-FC-Z/31/116 Fire protection thru-beam sensor

However, the door must not close when persons or objects are in the closing area. Legislation consequently requires monitoring with appropriate safety devices. The technical challenge is to ignore the smoke and at the same time reliably detect objects in it. These certified photoelectric sensors fulfill this function.

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  • Compact fire protection photoelectric sensor for safety devices on fire barriers
  • Approval in accordance with VdS Test Report FSA and externally monitored manufacture (‹ Symbol)
  • Not sensitive to ambient light, even with switched energy saving lamps

Technical Data

General specifications
Effective detection range 0 … 10 m
Threshold detection range 10 m
Light source LED, 660 nm and IRED, 880 nm
Light type modulated visible red light and modulated infrared light
Alignment aid LED red (in receiver lens)
illuminated constantly: beam is interrupted,
flashes: reaching switching point,
off: sufficient stability control
Diameter of the light spot approx. 0.2 m at 10 m
Angle of divergence Emitter 1.2°,
Receiver 5°
Ambient light limit 50000 Lux
Functional safety related parameters
MTTFd 490 a
Mission Time (TM) 20 a
Diagnostic Coverage (DC) 0 %
Indicators/operating means
Operation indicator LED green
Function indicator LED yellow:
1. LED lit constantly: signal > 2 x switching point (function reserve)
2. LED flashes: signal between 1 x switching point and 2 x switching point
3. LED off: signal < switching point
Control elements Light-on/dark-on changeover switch ; Time adjuster
Electrical specifications
Operating voltage 12 … 240 V AC/DC
Power consumption ≤ 3.5 VA
Switching type light/dark on, switchable . (selectable, light/dark switching is only activated if the receiver has ‘dark on’ selected.)
Signal output Relay, 1 alternator
Switching voltage max. 250 V AC/DC
Switching current max. 2 A
Switching power DC: max. 50 W AC: max. 500 VA
Switching frequency 25 Hz
Response time 20 ms
Timer function ON delay (GAN), OFF delay (GAB), one shot (IAB), ON delay-OFF delay (GAN-GAB), programmable
adjustment range 0.1 …10 s
Standard conformity
Standards EN 60947-5-2
smoke insensitive up to 2 dB/m ( EN 54-12 )
Approvals and certificates
EAC conformity TR CU 020/2011
TR CU 004/2011
Protection class II, rated insulation voltage ≤ 250 V AC with pollution degree 1-2 according to IEC 60664-1 Output circuit insulated from control circuit in accordance with IEC 61140.
The protection class 2 is only valid when the terminal compartment is closed.
CCC approval Certified by China Compulsory Certification (CCC)
Approvals VdS/DIBt certificate of compliance No. 25021
Ambient conditions
Ambient temperature -40 … 60 °C (-40 … 140 °F)
Storage temperature -40 … 75 °C (-40 … 167 °F)
Relative humidity 30% … 85%   non-condensing ; Non-icing
Mechanical specifications
Degree of protection IP67
Connection terminal compartment with 8 spring-loaded terminals for wire cross section 0.5 … 1.5 mm2 , Insulation stripping 7.5 … 8.5 mm , M16 x 1.5 cable gland
Housing Plastic ABS
Optical face Plastic pane
Mass 200 g (emitter and receiver)

Download Datasheet: Pepperl+Fuchs LA28/LK28-FC-Z/31/116 Fire protection thru-beam sensor