Why is my RCD tripping when doing a Zs test and the tester is on no trip

Welcome! Please register with the IET to join the community. It's free and takes less than five minutes.

Whoops, you don’t have access to that! Please register with the IET to join the community and access this area.

We're about to take you to the IET registration website. Don't worry though, you'll be sent straight back to the community after completing the registration.

I'm already registered with the IET