IDEC SE2L — Safety Laser Scanner Lockout

IDEC · intermediate · 25 min

When an IDEC SE2L safety laser scanner detects an internal error it goes to lockout and drops all its OSSD and warning outputs. Learn what lockout means, why disabling the interlock won't help, how to reset it, and which wiring to check with SLS Project Designer.

ℹ️ On an IDEC SE2L, a self-diagnostic error puts the scanner into lockout — OSSD1/2, OSSD3/4, WARNING1, WARNING2 all switch OFF. Key point: in an error lockout the OSSDs stay OFF even if the interlock is disabled — you must remove the error and restore power to recover.

What lockout is

The IDEC SE2L safety laser scanner continuously runs a self-diagnostic. When it detects an error and cannot operate normally, it switches to the lockout state. In lockout, all safety and warning outputs go safe:

• OSSD1/2, OSSD3/4, WARNING1 and WARNING2 all switch to the OFF state.

That's the scanner refusing to signal "clear" because it can't trust itself — the machine it protects should stop.

Why disabling the interlock doesn't help

A crucial distinction people get wrong: if the SE2L is in lockout due to an error, the OSSDs remain OFF even if the interlock function is disabled. Lockout is not the same as a normal interlock waiting for a reset — it's a fault state. So you can't "turn off interlock" to make the outputs come on; you have to clear the underlying error.

How to reset a lockout

The recovery is deliberately simple and safe: after removing the error, restore power to the SE2L to release it from the lockout state. In practice:

1. Identify and remove the error the scanner is reporting (see wiring, below).
2. Power-cycle the SE2L — restoring power releases the lockout once the error is gone. If the error is still present, it will lock out again immediately.

Check the safety wiring

Many SE2L faults are external wiring problems on its safety circuit. Check the connections for:

• OSSD output wiring (shorts to 24 V/0 V or between channels will fault it),
• EDM (external device monitoring) input — the feedback from the contactors/relays it controls,
• RESET input wiring.

Configure restart behaviour in SLS Project Designer

The SE2L is configured with SLS Project Designer. There you set Automatic restart, manual restart, or manual start interlock — choose the right one for the guarded application. Also: changes made during configuration must be recorded and saved — use the report function in SLS Project Designer so the safety configuration is documented (important for validation and audits).

Step-by-step

1. Lockout (all OSSD/WARNING off)? It's a fault state — disabling interlock won't turn outputs on.
2. Read the reported error and check the OSSD, EDM and RESET wiring.
3. Remove the error's cause (wiring short/feedback mismatch, obstruction, or configuration).
4. Restore power to release the lockout (it re-locks if the error persists).
5. Verify restart mode in SLS Project Designer and save the report; re-validate the protective function.

Never do this

Never jumper the OSSD/EDM or force a restart to get an SE2L out of lockout without finding the fault — lockout means the scanner can't guarantee protection. Fix the wiring/cause, power-cycle to clear, and re-validate per your risk assessment.