Leviton Telcom 420MI12WLEV 20A Mechanical Interlock

Product Description

The LEVITON TELCOM 420MI12WLEV is a 20-amp mechanical interlock designed to prevent two circuit positions from being energized simultaneously. Mechanical interlocks are a standard safety hardware accessory used in electrical panelboards, load centers, and switchgear where mutual exclusivity between two breaker positions must be enforced at the mechanical level. This device provides a physical barrier mechanism that blocks one breaker from being switched on while the other is in the on position, supporting reliable transfer switching and code-compliant installations.

The 420MI12WLEV is suited for use in residential and light commercial electrical applications where a mechanical interlock solution is required between two adjacent or specified breaker positions. It is typically installed by licensed electricians during new panel construction or retrofit transfer switch configurations, including generator interlock setups where a utility feed and a generator feed must be interlocked to prevent back-feeding.

Key Features

• 20-amp rated mechanical interlock for electrical panelboards and load centers
• Prevents simultaneous energization of two interlocked circuit positions
• Hardware accessory category — sold as individual unit
• Supports code-compliant generator interlock and transfer switching configurations
• Mechanical design requires no wiring or control voltage to operate

Compatibility

Designed as an OEM-style mechanical interlock accessory for electrical panelboards and load centers requiring 20A interlock hardware. Confirm compatibility with your specific panel model before ordering.

Installation Notes

Installation should be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and any applicable local codes. De-energize and lock out the panel at the utility disconnect before beginning any installation work. Mechanical interlocks must be mounted per the manufacturer instructions to ensure proper engagement and disengagement between breaker handles. Do not modify the interlock mechanism or force breaker handles past the interlock resistance.