Three phase Type A RCD confusion.

[GBDamo]

Was testing a EV charge point today and noticed the internal RCD was TP device with only a single phase supply and load in use (L1).

There was 245V either side of the RCD but the test button didn't function.!!

Is it possible the test button is fed from one of the phases that is not used, (L2,L3).

The RCD tested OK at 1x & 5x.

This looks to be how the charger was manufactured.

Anyone seen similar?

 

[Julie.]

The diagram on the rcd usually shows which phase the test button is on.

<satire>
Although it almost certainly failed recently as it must have worked on each of the 6 monthly tests routinely carried out
</satire>

 

[AJshep]

I know if you want to use a 4 pole RCCBs without a neutral you would insert a resister (correct valve for rcd) between an outgoing phase and neutral terminal. (See Schneider link)

I assume your correct the test button must be linked through an output, sounds to me like a manufacturers fault.

 

[GBDamo]

The diagram on the rcd usually shows which phase the test button is on.

<satire>
Although it almost certainly failed recently as it must have worked on each of the 6 monthly tests routinely carried out
</satire>

There must be thousands of EV chargers that are serviced annually, as the ones I do are.

We do test the RCD but only annually.

 

[Julie.]

There must be thousands of EV chargers that are serviced annually, as the ones I do are.

We do test the RCD but only annually.

I was only making comment about the number of rcd with the test 6 monthly label, yet hardly any are, in all honesty, I haven't checked mine within 6 months!

The test button is usually l2- n , but not always, but the diagram on the rcd shows which phase it's connected to