Yet another RCD tripping problem

[athelstan]

I wonder if you kind folks could shed any light on my problem, bearing in mind that I know nothing of electrics.
I have recently had a new board installed which is a mixture of MCBs and RCDs.
On trying my air compressor for the first time it immediately tripped the RCD. It is a 2hp compressor with a capacitor. I had no problems with my old board which had only MCBs. I have tried it on a large generator and it starts and runs fine. I have checked the wiring from the plug and that is OK.
Does this mean that I can no longer use an air compressor and will I have problems with any other tools?
After all the money I spent getting a new board I am not a happy bunny!

 

[JohnD]

Motors somewtimes do this, but consider a possible cause, given that:

the RCD is intended to trip when an event occurs that causes an unsafe condition due to earth leakage

and

The RCD trips when you start your compressor

What else is on the RCD that trips? you may have cumulative leakage if there are multiple circuits.

 

[Steve]

There may be nothing wrong with the compressor, having large motors on an RCD is never a good idea, but it is possible to eliminate RCDs if the circuit is designed correctly.

 

[Spark123]

Have a word with an electrician and see if they can pop around and test out your compressor with an Insulation Resistance Tester (AKA Megger).

 

[athelstan]

Thanks for your replies folks, very much appreciated. I'll get the compressor looked at by someone qualified.