Pressure washer trips fuse?

[Andehh]

I bought a Nilfisk E140 pressure washer, first time I used it tripped the garage and main house fuse box.

Resetting them, and it tripped it again.

I sent it back figuring electrical fault but the replacement doe exactly the same.

The main & garage fun boxes are set at 16amps,and they garage has nothing of high power usage in it. An old hi-fi and electrical garage door.

Anyone ever had similar issues? Could increasing the fuse size (via electrican) be an option?

For what it worth, it's a new build house, fuse box installed by qualified electrician a year ago a part of new kitchen installation.

Thanks

[Andehh]

No issues when plugging into the 32amp kitchen ring circuit.

Yes, it's not tripping the 13amp plug fuse, but it is tripping both the garage and main house 16amp RCDs. Both get flipped when I use the garage circuit.

[Andehh]

Yes, both ''fuse boxes' have RCD. The one in the kitchen is a metal box, brand new, to comply with the latest Regs.

One in the garage is a plastic one, with a master red 'cut off' and two RCD breakers. One for the lights, one for the 2 x double sockets and elec garage door.

Pressure washer is rated at 2100w, it replaced my old Vax one which is rated at 2000w.


Both Nilfisk pressure washers were refurb'd but bone dry when i tried them, neither managed to get water through before tripping the RCDs.

[Andehh]

motco said:

The obvious conclusion is that your 32A kitchen circuit that does not trip is not on an RCD. Is it the same circuit as used by your fridge/freezer?

Yes it is! Though I do think it is on a RCD, looks the same as the garage except the garage is 16amps & the other is 32amps.

[Andehh]

Jonesy23 said:

It might be earth leakage (though not necessarily due to a fault) or it could just be a high inrush current causing the trip.

If a higher capacity RCD of the same type and trip level (both 30mA?) is ok then I would suspect the instantaneous current from inrush is underlying issue.

Neighbour's father who was an electrician recons it is the high rush of current on initial start up and the RCD may just be particularly sensitive to it.

Can I risk increasing the garage RCD to 20amps, instead of 16amps, to compensate for this?

[Andehh]

Thanks for the comments guys, already trying to get hold of my regular electrician to come and have a look. Just trying to understand it first.

eliot said:

This is a 10A type B MCB - These come in different current ratings and curves B,C,D

Almost all Domestic installations use a type B, changing to type C or even D allows a higher initial surge - but as Smiler pointed out above, you need to check your earth loop impedance to make sure the fault current is high enough to pop the breaker in the correct time.

That's the type that is in the house. Confusingly it doesn't always trip, but I need to 'reset' it to enable the garage to work - turning it off & then on again a few seconds later.




The one in the garage is below, this does trip:

[Andehh]

Friendly neighbor's father had a look & confirmed he thinks it needs a TYPE C MCB due to the start up of the motor (as per the posts above suggesting it! - thanks guys). He has offered to replace it for me, if I supply the replacement TYPE C MCB.

Is the below compatible with my box (image below)?
http://www.screwfix.com/p/bg-mcb-16a-c-type/78793


Thanks

Edited by Andehh on Friday 26th August 16:03

Edit to add, house is a new build from 2007 including the garage and wiring. New main fuse box installed last year and fully certified to the 2016 regulations, Inc it being metal etc

Edited by Andehh on Friday 26th August 19:02

[Andehh]

Thanks eliot, have ordered one.

He came over and had a look, and mentioned my main fuse box also has a 16a type b. This would likely trip instead now.

He has advised it'd be worth going for a 20a one if I ever intend to put more in the garage, but I am struggling to find one.

It is a BG 20A type C he recommended, but I can only find 16a type c at screw fix and the 20a ones seem rather elusive without paying £8 for postage for one.

Does anyone know a fair place to buy one?

Thanks again

[Andehh]

I hope so, got my usual electrician to have a look and this advice was from him. He is fully certified and I've never had reason to doubt his professionalism to date.

The cable into the garage fuse box Looks to be around 3mm from me checking? Understand standard electrical 3 core is 2.5mm(?) but this looks bigger. It's an armoured cable over approx 10m.

Thanks eliot

Edited by Andehh on Sunday 28th August 10:51