The L51 is designed for demanding environments where plastic-bodied switches have a limited service life. It features a full metal body and cover, a 10 million mechanical-cycle rating, IP65 sealing, and an M20 gland entry for a secure, sealed cable connection. The metal roller arm gives reliable snap-action detection wherever a moving door, guard, or slide needs positive position sensing.
Commonly used for:
- Door/lid shutoff on kilns and ovens
- Cold room and refrigerator doors
- CNC and motion control
- Machinery including lathes and mills
- Conveyors
Compare The EMAS L51 & L61 Range
L51 series - IP65, screw terminals with PG13.5 / M20x1.5 gland entry:
- L51K13PUM211 (10mm metal plunger)
- L51K13MIM311 (14mm metal roller lever)
- L51K13MEM121 (18mm metal roller arm) (this item)
- L51K13MEL121 (50mm rubber roller arm)
- L51K13ROP101 (9mm plastic rod lever)
- L51K13SOM101 (2mm metal spike spring lever)
- L51K13SOM102 (7mm metal blunt spring lever)
L61 series - IP67, supplied pre-wired with 2m cable:
- L61K13PUM211 (8mm metal plunger)
- L61K13MUM331 (13mm metal roller plunger)
- L61K13MEM121 (18mm metal roller arm)
- L61K13MEP121 (18mm plastic roller arm)
Not sure which series to choose? See the L51 vs L61 comparison in our Foot, Limit & Micro Switches collection.
Technical Details
Frequently Asked Questions
What does "snap action" mean for this switch?
Snap action means the internal contacts switch quickly and positively once the actuator passes a set trip point, rather than gradually — giving a clean, repeatable signal regardless of how fast or slow the roller arm is moved.
Is the metal body necessary, or would a plastic version do?
If your application involves rough handling, heavy vibration, high-cycle use, or extreme temperatures (kilns, cold rooms), the metal body's 10 million mechanical cycle rating and -25°C to +80°C range make it the more durable choice over a standard plastic-bodied limit switch.
What size cable gland do I need?
It has an M20 gland entry, so use an M20 cable gland matched to your cable diameter to maintain the IP65 seal.
Can I use this on a cold room or freezer door?
Yes — with an operating range down to -25°C, it's suited to cold storage and refrigerator door interlocking, which is one of its more common applications.
Industry Applications
- Kilns, ovens & cold storage — door/lid interlocking across extreme temperature ranges
- CNC & machine tools — position sensing on lathes, mills, and motion control systems
- Conveyors & material handling — robust position/limit detection in high-cycle industrial settings