RCBO tripping

I had a FuseBox F2007M fitted in my garage a couple of months back, it replaced and older CU which was working fine but as I was having a EC charger installed for an electric car I was told it needed upgrading. The 16amp RCBO in the pic supplied and electric garage door and socket in the garage. The 13 amp socket has been used for the last couple of months for some small (load) stuff - no problems. Today, for the first time since this CU was installed I decided to wask the car using my Karcher K7 Pro plus and an attachmnet the squirts 'snow foam.' Each time I used the snow foam attachment it tripped the RCBO. (I presume the snow foam being thicker than water causes the Karcher motor to work harder.

Surely this can't be right - any ideas / suggestions?

cant imagine a domestic pressure washer pulling more than 32a. have you tried the machine in another socket on a different circuit? that way you can eliminate the machine as being faulty

rated at 3000w so shouldnt pull more than 12 or 13a.

Because its a RCBO you don't know if its a N-E fault or an over load

My money is its start up current - so try powering it from a 32A socket circuit and see what happens

Does it do it without the foam lance?
Does it do it on switch on ? or when trigger is pulled?

Thanks for the helpful replies . . . when I plug it into a socket off the main house CU it runs without a problem. I wonder whether the 16amp RCBO is too sensitive and perhaps needs shanging to something less sensitive. I note that the trip units for plug sockets in the main hosue CU are all 32amp AND the old CU in the garage was 32amp

Forty_Two said:

Thanks for the helpful replies . . . when I plug it into a socket off the main house CU it runs without a problem. I wonder whether the 16amp RCBO is too sensitive and perhaps needs shanging to something less sensitive. I note that the trip units for plug sockets in the main hosue CU are all 32amp AND the old CU in the garage was 32amp

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I would recommend you get the installer back to do the necessary

I suspect that its just that the start-up surge of your washer pump can trip a 16 amp Rcbo. I have a 16amp Rcbo protected outdoor socket which I can't use for a couple of motorised tools I have. Both my chainsaw and large angle grinder trip it consistently. Both tools work perfectly on 32amp circuits. I've sometimes also used a (reasonably long) extension lead on the 16 amp circuit, where the added resistance has stopped the tripping.

I agree with Geoff
RCBO type C or try 20a RCBO... if the electrician is local he might swap it out for free being he installed a new board because of an EV charger !!!

Hmm picture shows a tripped 32amp RCBO, but does not seem to have any connections to it.

Well spotted Mike.J perhaps it had new cables that can't be seen without x-ray eyes.

But he did state it was a 16amp tripping so its just a spare rcbo

Thanks again for the helpful replies . . . . the spare 32amp on the far right is waiting for he EVC connection, it is the 16amp that is tripping and to add to the clues . . . it does not trip when I plug in the Karcher but as soon as I connect the water to the Karcher i.e. put it under pressure the 16amp trips.
The EVC installer is not the same person who fitted the CU, he will be taking out thet 32amp RCBO and replacing it with a dual pole RCBO. I coudl ask him to replce the 16amp RBO with the single pole 32amp RCBO that is coming out - is that a good idea'?

no, you cannot just change a 16 to a 32a

Forty_Two said:

Thanks again for the helpful replies . . . . the spare 32amp on the far right is waiting for he EVC connection, it is the 16amp that is tripping and to add to the clues . . . it does not trip when I plug in the Karcher but as soon as I connect the water to the Karcher i.e. put it under pressure the 16amp trips.
The EVC installer is not the same person who fitted the CU, he will be taking out thet 32amp RCBO and replacing it with a dual pole RCBO. I coudl ask him to replce the 16amp RBO with the single pole 32amp RCBO that is coming out - is that a good idea'?

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You said connecting the water trips the RCBO which makes me wonder if the trip is not due to surge current (the 16amp part of the RCBO) but instead is caused by a leakage fault within the washer tripping the 30mA part of the RCBO?

How close is the socket to the RCBO? as you could rewire it using a 4mm cable( assuming it was wired in 2.5mm?) then you can then change the 16a for the 32a rcbo

runningpiglet said:

You said connecting the water trips the RCBO which makes me wonder if the trip is not due to surge current (the 16amp part of the RCBO) but instead is caused by a leakage fault within the washer tripping the 30mA part of the RCBO?

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If it was the RCBO tripping due to earth leakage then the value of the breaker is almost irrelevant.

Most modern dual pole RCBO's have an indicator on them to tell you if it was an earth fault that caused it to trip out, certainly the Hager ones I use do.

https://www.electricalwholesaler.ie...reakers/hagerrcbo2p1pn6kab25a30maaclassad925j

Mike.J said:

Most modern dual pole RCBO's have an indicator on them to tell you if it was an earth fault that caused it to trip out, certainly the Hager ones I use do.

https://www.electricalwholesaler.ie...reakers/hagerrcbo2p1pn6kab25a30maaclassad925j

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How is that relevant they are nothing like the OPs devices.

Perhaps not, but useful information for anyone in the future, or is thread drift not allowed on "The UK's Friendliest Electrical Forum"

Mike.J said:

Perhaps not, but useful information for anyone in the future, or is thread drift not allowed on "The UK's Friendliest Electrical Forum"

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Not taking sides here, but your input wasn't really helpful, given the clear information the OP had posted.