Safety light curtains create a vertical plane of light beams across an opening and stop the machine when a beam is broken, ideal for machine fronts and access points. Safety laser scanners watch a configurable area, often horizontally on the floor, and can slow or stop machines and mobile robots based on zones. Choose based on your risk assessment, required safety level and layout.
Guarding keeps people safe and machines productive.
Compared
| Light curtain | Laser scanner | |
|---|---|---|
| Detection | Vertical plane | Configurable area |
| Typical use | Machine openings | Floor zones, mobile robots |
| Zones | Single field | Warning and protective fields |
| Mounting | Pairs across an opening | Single unit |
| Muting | For material passing through | Zone switching |
Selection steps
- Complete a risk assessment.
- Determine required PL or SIL.
- Calculate safety distances.
- Choose device and controller.
- Validate and document.
Work with a qualified integrator. See automation ROI and machine vision basics. Browse safety and planning.
Compare safety relays and configurable safety controllers when reviewing the control architecture for a safety function.
Also compare a safety scanner and gate interlock as distinct device roles in the safeguarding design.
Common questions
What safety ratings matter?
Performance level (PL) under ISO 13849 and SIL under IEC 62061, plus the device type for light curtains. Your risk assessment sets the requirement.
How far must a light curtain be from the hazard?
A safety distance calculated from the machine's stopping time and the device's resolution and response time, per standards such as ISO 13855.
Can scanners slow a robot instead of stopping it?
Yes. Scanners often use warning and protective zones to slow and then stop, reducing downtime.