Don’t Get it Wrong - Insulation Resistance Test

thank you

You explained that we must do it and that it's vital but unless I missed it, you didn't explain why it's important.

Hager rcbos have it printed on the outgoing terminals that you can carry put the IR testing when the device is in the off position.

Earth I thought that we aren’t using that word no more so as to confuse the DIY guy should it not be the CPC

How do we do IR test with RCBO’s (single pole) & SPD in place? What needs disconnecting?
Thanks