RCD on TT installations won't trip on x5

[David Rann]

I do a lot of ev charging so do a lot of rod installations. If impedance is over 100 ohms on the rod the RCD will trip on x1 but will not trip on x5. I have tried different RCDs etc but this always seems to be the case....anyone know why this is? The RCDs are type A so DC sensitive..

 

[The Ghost]

I would discuss the above with the manufacturers of such trips especially the technical department. As a matter of interest is it the case that all EV points have to have an earth rod?

 

[cliffed]

Sure you got the right rcd rating on the tester

 

[The Ghost]

Hysteresis, possibly??? maybe not.

 

[AJshep]

Just curious, If you carry out the RCD test directly on the output of the RCD with the charging point removed does the RCD still fail 5x ?

Never done a EV charging point but have installed plenty of Earth Rods some mesauring over 100 Ohms had the odd one or two fail but most pass.

 

[PEG]

HI,what is the full spec,and positioning,of the RCD?