Page top


Omron uses cookies to improve your experience on this website. By continuing to use the website, you hereby agree to our Privacy and Cookie Policy

Lead Contents

Safety Limit Switch: Snap Action

FAQ No. FAQ02351

Primary Contents


What is a snap action?


SPST-NC + SPST-NO Contact (Snap Action) Example

The SPST-NC + SPST-NO contact snap action switches have the direct opening mechanism (forcibly opened contacts) defined under EN 60497-5-1. The NC contact side is the only side with a direct opening mechanism (forcibly opened contacts).

1. When contact welding occurs.

2. When contacts are being pulled apart.

Safety cam directly pushes up the movable contact blade.

3. When contacts are completely pulled apart.