Schmersal safety light curtains and photoelectric sensors are optoelectronic protective devices (AOPD) compliant with international safety standards EN 61496 and EN ISO 13849. The portfolio consists of three main product lines: SLC light curtains (dense multi-beam for finger/hand protection), SLG light grids (few-beam for perimeter safeguarding) and SLB single-beam safety photoelectric barriers. An invisible protective barrier is formed by infrared light beams. If personnel enter the hazardous zone and interrupt the light path, the machine triggers an immediate safe stop. Equipped with blanking, muting and start interlock functions, they eliminate the need for physical guards, balancing machine safety and operational accessibility. They are widely adopted for isolating hazardous zones of various automated machinery.
20 mainstream models of Schmersal safety light curtains and photoelectric sensors:
SLC440-ER-0330-14
SLC440-ER-0650-30
SLC440COM-ER-0810-14
SLC445-ER-1050-30
SLC240COM-ER-0570-35
SLG440-ER-04
SLG440COM-ER-03
SLG445-ER-02
SLB440-ST
SLB240-LST
SLC440IP69K-ER-0730-30
EX-SLC440-ER-0490-14 (Explosion-proof Version)
EX-SLG440-ER-0500-03
SCLC440-ER-0410-14
SLC440COM-ER-1210-30
SLG440AS-i-ER-04
SLC445-ER-1450-14
SLB440-H (Low-temperature Heated Version)
SLC440-ER-1610-30
SLG440COM-ER-04-L
Typical application industries: robot workcells, stamping machines, injection moulding equipment, automated packaging lines, automated warehousing systems, lithium new energy production lines, woodworking machinery, port automation equipment, food & pharmaceutical processing machines, printing production lines, logistics sorting systems, die-casting equipment, construction machinery consoles, elevator automation systems and chemical explosion-proof production lines. Common applications include hazardous access protection for machine tools, robot perimeter guarding, side protection of conveyor lines and isolation of pick-and-place stations to realise dynamic human-machine collaborative safety.
Compared with mechanical safety door switches and conventional limit switches, Schmersal safety light curtains and photoelectric sensors feature five core advantages:
First, non-contact invisible protection for convenient access. Physical guards and safety doors are not required. Operators can freely enter working areas without mechanical wear. Failures such as hinge jamming and lock damage are eliminated to improve production efficiency.
Second, comprehensive safety ratings for different risk levels. Type 2 and Type 4 safety categories are available, and high-end models achieve PL e / SIL3 safety level. Options include 14 mm finger protection, 30 mm hand protection and multi-beam perimeter protection. Beam coding technology prevents false triggering caused by external light interference.
Third, intelligent built-in functions suitable for automated production lines. Blanking, material muting, start interlock, EDM contactor monitoring and dual-reset modes are supported. COM variants integrate Bluetooth, enabling parameter configuration, fault diagnosis and operation data recording via mobile App for efficient commissioning and maintenance. AS-i bus integrated models facilitate networking for smart manufacturing systems.
Fourth, complete protection specifications for versatile environmental adaptability. Standard models reach IP67 protection class, while hygienic versions achieve IP69K to withstand high-pressure hot water cleaning in food industry. Explosion-proof variants are available for chemical dust-hazard zones, and heated low-temperature models suit cold storage and outdoor environments. Aluminium alloy housings deliver excellent shock resistance against dust and oil contamination.
Fifth, extensive model options and flexible installation. Protective height and detection distance are configurable, with maximum detection range up to 60 metres. Reflector mirror mounting enables corner area protection with a single set. Uniform M12 connectors and multiple mounting brackets are provided. Full-range CE and UL certifications support global machinery export.
With the popularisation of human-machine collaborative automation, fixed physical guards restrict material flow and operator movement. Featuring flexible non-contact protection, reliable safety performance and intelligent commissioning capabilities, Schmersal SLC/SLG/SLB safety light curtains and photoelectric sensors have become mainstream solutions for hazardous zone protection of machine tools, robots, packaging and new energy equipment, building efficient and compliant safety barriers for automated production lines worldwide.
Related Safety Light Curtains
Browse the complete Schmersal Safety Light Curtains range. Representative models available through Glorient:
Safety light curtains typically provide PL e / SIL 3 protection. For how this maps to your required level, see SIL vs PL Explained: Performance Levels, Safety Categories and Component Selection.
Frequently Asked Questions
What is the difference between the SLC, SLG and SLB series?
SLC is the standard safety light curtain family; SLG covers compact light grids and single-beam systems; SLB is the basic entry-level series. They differ in resolution, protective height and feature set, so the right choice depends on the guarding task.
What resolution should I choose - 14 mm or 30 mm?
14 mm (finger resolution) is required when fingers could reach the hazard through the curtain; 30 mm (hand resolution) is sufficient for hand and arm detection. The resolution determines the minimum detectable object size and directly affects the calculated safety distance.
How is the safety distance for a light curtain calculated?
The safety distance equals the approach speed multiplied by the total response time (curtain response time plus machine stop time), plus a resolution-dependent constant, as defined in EN ISO 13855. Always have the final installation validated by a safety engineer.