Engineering Sizing & Global Procurement Guide for Safety Light Curtains

The primary technical distinctions revolve around internal fault detection redundancy, optical beam tolerance, and maximum achievable Performance Level (PL) under ISO 13849-1:

• Type 4 Safety Light Curtains: Mandated for high-risk applications (SIL 3, PL e, Category 4). They utilize dual independent microprocessor channels with continuous diagnostic self-testing. A single internal hardware fault will never result in a loss of the safety function. Their Effective Aperture Angle (EAA) is limited to ±2.5° to prevent optical reflection bypass.
• Type 2 Safety Light Curtains: Suitable for lower-risk applications (SIL 1/2, PL c/d, Category 2). They rely on periodic diagnostic tests performed by an external controller. A fault occurring between test cycles could cause a temporary loss of safety function. Their EAA is wider at ±5.0°.

Safety distance calculation must follow EN ISO 13855 / OSHA 1910.217 guidelines using the standard formula: S = (K × T) + C.

Where K is the hand intrusion speed (2000 mm/s), T is the total stopping time (including safety curtain response time, safety relay delay, and machine mechanical braking time), and C is the depth penetration factor ($C = 8 \times (d - 14)\text{ mm}$ for hand resolution). Our application engineering team at Lubi Electronics can run verified digital stopping-time measurements for your specific line setup.

Both functions allow material movement through an optical barrier without tripping the safety control circuit, but their operation differs significantly:

• Muting: A temporary, automatic bypass of the entire safety curtain triggered by external muting sensors (e.g., photoeyes or inductive proximity switches) during a non-hazardous machine phase (such as a pallet exiting a robotic cell).
• Blanking: A continuous, selective deactivation of specified optical beams within the sensing field. Fixed Blanking ignores stationary objects like mechanical brackets, whereas Floating Blanking allows a movable workpiece to pass through a restricted beam count while maintaining active protection across all remaining beams.

High-end safety light curtains engineered by Lubi Electronics employ narrow-band optical filters, infrared pulse modulation (850–940 nm), and digital cross-talk suppression. For severe industrial environments:

• Welding & Glare: Specialized bandpass filters reject ambient welding arcs and high-frequency LED lighting glare.
• Washdown & Dust: IP67/IP69K rated PMMA acrylic or polycarbonate tubular enclosures shield optics against high-pressure, chemical washdowns in food, beverage, and pharma applications.
• Vibration: Heavy-duty shock mounts prevent misalignment on stamping presses.

Yes. As a leading manufacturer of type-tested control panels with over two decades of engineering expertise, Lubi Electronics designs, wires, tests, and certifies custom safety enclosures. We integrate safety light curtains directly with safety relays, programmable safety PLCs (such as Siemens PROFIsafe or Rockwell CIP Safety), drive safe-torque-off (STO) loops, and emergency stop circuits—delivering a turnkey, documented panel ready for immediate global deployment.

Every safety system dispatch includes a complete engineering documentation package: CE Declarations of Conformity, TÜV Type Examination certificates, detailed CAD schematic drawings, IO-Link parameter maps, user installation manuals, and Factory Acceptance Test (FAT) sign-off reports to ensure smooth compliance auditing by local regulatory bodies worldwide.