The AREL DC1-2C is a key-operated trapped key interlock switch designed for machine guarding applications. It combines electrical power isolation with a mechanical key-capture system to enforce safe access procedures — personnel cannot enter hazardous areas until the machine is isolated and the key is released.

Operating Principle

Turning and removing the key from the DC1-2C opens the 2NO+2NC contacts, isolating the machine from its power supply. The freed key is then used to unlock an access door or gate. While the door is open, the key remains trapped in the door lock, preventing the machine from being re-energised. Only after the door is closed and the key is returned to the DC1-2C can the machine be restarted.

Typical Application

In a single-door machine guarding setup, the DC1-2C is paired with an AREL DP1 door lock. This configuration enforces a forced sequence: isolate power, release key, unlock door, perform maintenance, close door, return key, re-energise. The system prevents accidental machine start-up while personnel are inside the protected area.

Technical Specifications