What causes fault code SAFE-LC1 (Light Curtain Fault — Beam Blocked or Misaligned)?

Physical object blocking one or more beams — product, debris, or tool left in the curtain field. Emitter or receiver lens dirty — dust, overspray, or condensation. Light curtain knocked out of alignment — vibration or impact shifted one column. One or more LEDs in the emitter failed — dead beams in the curtain. Sunlight or high-intensity ambient light overwhelming the receiver — curtain near dock door or window

How do I fix fault code SAFE-LC1?

Clear any objects from the light curtain detection field — walk the full width of the curtain. Clean emitter and receiver lenses with lint-free cloth — both columns. Check alignment — most light curtains have alignment LEDs on both emitter and receiver, all should be solid green. If one beam is permanently blocked but field is clear, the corresponding LED in the emitter may have failed — check beam-by-beam status. If ambient light interference, install light curtain shrouds or hoods to block direct sunlight. Verify wiring to light curtain controller — check for loose connections on the safety circuit

Light Curtain Fault — Beam Blocked or Misaligned

SAFE-LC1

Safety light curtain has one or more beams permanently blocked or misaligned. Machine cannot reset because the light curtain does not show all-clear.

medium general packaging palletizer

safety light curtain beam alignment block reset

Probable Causes (ranked)

Physical object blocking one or more beams — product, debris, or tool left in the curtain field
Emitter or receiver lens dirty — dust, overspray, or condensation
Light curtain knocked out of alignment — vibration or impact shifted one column
One or more LEDs in the emitter failed — dead beams in the curtain
Sunlight or high-intensity ambient light overwhelming the receiver — curtain near dock door or window

Fix Steps

1 Clear any objects from the light curtain detection field — walk the full width of the curtain
2 Clean emitter and receiver lenses with lint-free cloth — both columns
3 Check alignment — most light curtains have alignment LEDs on both emitter and receiver, all should be solid green
4 If one beam is permanently blocked but field is clear, the corresponding LED in the emitter may have failed — check beam-by-beam status
5 If ambient light interference, install light curtain shrouds or hoods to block direct sunlight
6 Verify wiring to light curtain controller — check for loose connections on the safety circuit

Field Trick

When a light curtain won't reset but the field looks clear, bend down and look through the curtain at floor level. A small piece of product or a pallet board on the floor can block a bottom beam that you can't see from standing height. The bottom beams are the most commonly blocked because debris collects at floor level.

Suggested Replacement Parts

Parts matched to fault category: Light Curtain

Banner EZ-SCREEN LS Light Curtain P/N: LS2TP30-450Q88 Type 4, 30mm resolution, 450mm protective height, PNP OSSD

AutomationDirect $425.00 Amazon $480.00 Grainger $550.00

Prices are estimates. Verify part numbers match your equipment before ordering.

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