Transparent physical strip curtain hanging across a machine opening; illustrative image.

Physical Machine Curtain vs Safety Light Curtain: What’s the Difference?

“Safety curtain” can refer to two different device types. Flexible strips hanging across a machine opening form a physical curtain; a safety light curtain is an optoelectronic protective device. Pilz classifies these separately as physical safeguards and optoelectronic devices such as light curtains. Do not identify a physical strip curtain as the same part as a safety light curtain.

Diagram showing that a physical strip curtain and a safety light curtain are different device types.
General diagram; it does not show a specific machine, safety configuration, or device suitability.

How to identify a physical strip curtain

If flexible strips hang from a top rail across a machine opening, the part you are looking at is a physical strip curtain. Its appearance alone does not confirm that it satisfies a machine-safety function; that cannot be verified from an image or product name.

Illustrative scene documenting the existing strip curtain’s upper rail and part dimensions.
Measurements document the existing part only; they do not determine safety design or device suitability.

What to record in a parts enquiry

Record the machine maker, model, and serial number; any readable code on the old part; the curtain’s position on the machine; and a close-up photo of its upper mounting rail. If needed, note the existing strip’s dimensions as part-identification information and state which edges you measured. Those measurements do not select a safety device or establish whether machine protection is suitable.

If you mean a safety light curtain

If you see optical transmitter/receiver units with a manufacturer label, do not replace, move, or bypass the device based on appearance. Record the manufacturer and complete model code that can be read from outside, together with the machine nameplate details. Pilz lists light curtains among optoelectronic protective devices; follow the machine maker’s instructions and a qualified machinery-safety specialist’s assessment for model selection or integration. This article gives no sizing or installation instructions.

If you cannot tell which part it is, send the machine nameplate and a photo of the existing component to the machine maker or an authorized service source and ask them to confirm its role and complete code. For general machine-part documentation, see our machine and part identification checklist; it does not select a safety device.

This content was prepared automatically using search data and official technical sources.

Source: Pilz — Safeguards and safety devices on plant and machinery.

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