Type A RCDs Vs Type AC

[mattg4321]

Not enough information from the relevant manufacturers. Quelle surprise.

 

[Nigel]

The reason we should install DP (switched neutral) RCBOs in a TT system is only when an up-front RCD (100mA S Type) is installed so that we achieve selectivity and avoid nuisance tripping from a neutral - earth fault which would then trip the up-front RCD in fault conditions.

 

[davesparks]

How many of us own the appropriate DC RCD tester to test Type A RCDs?

You'd hope everyone who needs one does, though this is unlikely to be the case.

My MFT (Megger 1730) is capable of testing types AC, A and B RCDs and I think most common testers are capable of AC and A type.

 

[Andy78]

How many of us own the appropriate DC RCD tester to test Type A RCDs?

Me. Even though it is a bottom of the range Metrel MI300 of 8 years age.