Three Phase Wires in One Pole of RCCB

You have three-phase power coming in.

You are connecting all three wires to a single pole.

That is called a SHORT CIRCUIT BETWEEN THE LIVE WIRES.

The first problem is that it will cause breakers to trip/fuses to blow upstream in the power grid, knocking out power for your neighbors.

The second problem is that anyone near the panel when this gets power could be KILLED.

The third problem is that this would get the person who wired it up FIRED for not knowing the basics of electrical wiring.

I would Strongly Recommend that you go back to school and learn about electrical wiring before you try working with electrical power.

1) If this is a test or homework question and you don't know the answer - and you don't know why you don't know the answer - tell your teacher he's wasting his time. Then go over to the registrar's office and change your major to something that does not involve large quantities of energy.

2) If this is a real installation that you're standing near, drop everything this very second and run like hell.

Thank you, I wanted to use strong language like that, but the last time I did a 'what the he** are you thinking!?!' post to a question like this, it got deleted by the admins for being 'abusive.'

I guess I'm not allowed to yell at people for doing dangerous, self-destructive things. All I can do is fill out the 'observer' paperwork to help these people get the Darwin Awards they are so desperately trying to earn.

Today's Darwin Award goes to...

"There was supposed to be an Earth shattering ka-boom".

Worrying, isn't it?

3. If this is a wiring job you did yourself, put down your tools, go over to the nearest precinct office, and turn yourself in to the police. You will be safer there - and so will everyone else.

This will cause a massive cross phase short, an explosion will ensue destroying the breaker and damaging the equipment upstream...are you a terrorist?

Perhaps you mean only one of the phases and the neutral is going through the 2 pole RCCB?

No this won't work. Have a look at your local electrical codes and standards for more details, or hire a qualified electrician to perform this work safely and legally.

Yeah that makes a bit more sense, a three phase feed that he wants to separate into 3 single phase breakers....You still need a 3 phase main panel breaker....and 3 phase breakers to plug into the panel....

Yes, that, and the neutral really only exists if the XFMR output is 3-phase WYE, not Delta. Seems like a very unusual arrangement, one doomed for failure of one kind or another, and not in code in US or Canada?

Perhaps it's been done at the transformer.

A 120Y/208 volt three phase service is pretty much a North American thing. The connection between the bonding system and the neutral, to be code compliant, must be done at "both" spots.

Its sound to me like , you are trying to use 2 pole RCD (single phase) in a three phase four wire system (3- hot ,1- neutral) by shorting three phase into single phase-Very bad idea . I hope you learnt about 3-phase fault.

Best solution is to buy a four pole RCD and complete the wiring. If you dont know hire someone to sort it out.

If it a home work question, click the link below or use Solar eagle's diagram.

http://www.electricalonline4u.com/2015/11/how-to-wire-4-pole-rcd-circuit-breaker.html

Are you being serious? Or are you taking the P!SS?

Just take a moment and, think about what you are asking.

What would happen if you connected the 3 LIVE legs of a 3 phase supply together? Wait for it!

Are you sure it's a 3 phase supply?

Can you supply some pictures? I could with a good laugh.

<...Will this arrangement work fine?...> No, it won't work at all.

<...what problems will it cause?...> When energised:

• with good luck, the circuit protective device upstream will operate and disconnect the supply.
• with bad luck there will be a lot of explaining to do to the Loss Adjuster from the building's fire insurance company after the building has burned down, assuming the individual doing the explanation did not die during that event.

That it is installed in the first place is a great curiosity:

• Why would one need to ask on a global Engineering forum whether or not it would work if testing it at site would demonstrate this (rhetorical question - NNTR)?
• Why did the individual installing it not demonstrate its action by carrying out such a test (rhetorical question - NNTR)?
• Why is there no record of its having been tested that would obviate a need to ask these questions on a global Engineering forum (rhetorical question - NNTR)?

Disconnect the supply immediately. Engage a qualified electrician to install the correct RCCB for a 3-phase supply. Make sure that the test documentation for a correct installation is filed appropriately in case it is needed in the future.

What you should expect after energizing the system is a very loud bang and black ashes around.

At a rough guess, I think our friend has a single phase supply of a three phase supply.

Like everyone else I can’t figure out the three phases in to one terminal of the RCD.

Is this thread associated with http://cr4.globalspec.com/thread/112418/RCCB-tripping-after-change-of-supply. if it is I would suggest our friend leaves things well alone and calls an electrician.

BANG !