Need Help on Three-Phase Extension Cable

What National Code are you working to?

In Australia the earth can only be missing in a sigle phase 10A lead if the device is double insulated.

If not having an earth conductor in the appliance lead is permitted where you are, then so be it.

For testing purposes an adapter rig is fine.

But for normal use, you are compromising the protection level given by the RCD(ELCB). If a fault current of 20A occurs the breaker will not trip, but the lead will be carrying double it's rated current.

Result: FIRE!.... or worse.....

Why not upgrade your equipment appliance lead to 20A and be done with it?

The nationcal code would be Australia. The extension cable is for testing purposes. The thing is that 10A 3 phase cable has 3 Active and 1 Earth but the 20A 3 phase cable has 3 Active, 1 Neutral and 1 Earth. As its not my decision not to change it to 20A, I have to work around it and find a way of working with it.

obener ,

You could replace the source socket temporarily to accommodate the test plug, then re-install the correct socket after the test.

The neutral of the temporary socket will be vacant, but no issue.

Be sure to tag the temporary socket with the appropriate information until the test is complete and the socket returned to it's original configuration.

Regards, CJM

obener,

In Australia it is not worth your while trying to do it yourself. Apart from the possibility of trouble from your lack of knowledge or trying to interpret some post from another jurisdiction, the law will nail you especially if there is an incident.

If I tried to guide you, I'd also get nailed and loss of my electrical licence is not something I can afford. Yes electrical work in Australia requires a licence.

Hi obener,

I am the impression that you're not an electrician, it's is needing a very simple job to be performed but could be a dangerous for your equipment to be tested which is three phase unit, including to yourself by putting it into high risk! I also noticed that you are from Australia. I can remember the safety sign on the wall " DON'T MONKEY ELECTRICITY" when I was there for exposure training in 1996.

CJMcGill advised is almost perfect for me, except the word "you could" instead "the electrician could" how could you test a Three phase equipment where only for testing accessories (Extension cord) you don't have better idea or understanding. bear in mind that if the unit is Three phase (motor) and you wrongly supplied with single phase your motor will be damaged.

To hire the qualified technician or electrician will cost cheaper than to repair a damaged equipment + parts + downtime etc.

Come on MATE!!!

This is only a friendly advise.

Kind regards

Roman

Consult a locally-qualified electrician.