Make sure though that all the loads are off ie turn the MCBs off, at the CU, that the RCD protects, as you don't want any loads on the test.
Thank you sounds like an easier way of testing sorry guys i was getting confused.
So just to clarify at consumer unit have main switch off and RCDs AND MCBS in the on position then go to double pole switch or pullcord and test from their ?
It's a 2-lead test on the 1553.
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