What causes fault code SAFE-INTLK1 (Safety Interlock — Trapped Key System Fault)?

Operator has the key — key was removed from the lock box and not returned. Key is in the wrong lock — keys swapped between stations. Lock mechanism jammed — key won't turn or can't be inserted. Key broken in the lock — fragment stuck in the cylinder. Lock switch (if monitored electrically) not confirming key presence

How do I fix fault code SAFE-INTLK1?

Locate all keys in the trapped key sequence — verify each key is in its correct lock position. If a key is missing, find the person who has it — the key represents a person's safety lockout. If a key is in the wrong lock, return it to the correct position following the designed key exchange sequence. If a lock is jammed, do NOT force it — use graphite lubricant in the cylinder. If a key is broken in a lock, lock out the entire system and call the trapped key system manufacturer for extraction. Do NOT bypass trapped key systems — they enforce a physical safety procedure sequence

Safety Interlock — Trapped Key System Fault

SAFE-INTLK1

Trapped key interlock system fault. Key is not in the expected position, or the lock exchange mechanism has failed. Machine cannot start because the safety key sequence is incomplete.

high general conveyor packaging

safety interlock trapped key lock procedure access

Probable Causes (ranked)

Operator has the key — key was removed from the lock box and not returned
Key is in the wrong lock — keys swapped between stations
Lock mechanism jammed — key won't turn or can't be inserted
Key broken in the lock — fragment stuck in the cylinder
Lock switch (if monitored electrically) not confirming key presence

Fix Steps

1 Locate all keys in the trapped key sequence — verify each key is in its correct lock position
2 If a key is missing, find the person who has it — the key represents a person's safety lockout
3 If a key is in the wrong lock, return it to the correct position following the designed key exchange sequence
4 If a lock is jammed, do NOT force it — use graphite lubricant in the cylinder
5 If a key is broken in a lock, lock out the entire system and call the trapped key system manufacturer for extraction
6 Do NOT bypass trapped key systems — they enforce a physical safety procedure sequence

Field Trick

Trapped key systems get jammed when people use the wrong key or force keys that don't quite fit. Apply a small amount of graphite (not WD-40 or oil) to every key and lock once a year. Graphite lubricates without attracting dust. Oil in a lock cylinder attracts grit and causes the lock to jam worse over time.

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