Caravan park

[bks]

Hi everyone,
otherday i was testing a caravan (EICR) and found two RCD in series one at hook up point and other one is inside the van. While I do the RCD test it trip sometimes inside and sometimes outside the box. So I have been in and out from caravan few times to reset the RCD. Please anyone can advice me how would you test both RCD same time or easiest way to test both. Many Thanks.

 

[jaydee81]

your rcd at the hook up point is the easiest one to test, disconnect caravan and test at rcd terminals the caravan rcd not so easy only way to test it would be too temporary link out or replace hook up rcd with main switch and replace after test

 

[markc123]

Ahh Caravan's the strange world.

Regulation 314.1 requires the prevention of nuisance tripping - i hear alot of people doing away with the RCD's inside the caravan...

Now, lets look at section 708.

Regulation 708.553.1.12 states that the outside distribution box (to the caravan pitch) must have a RCD protecting the commando.

Static Caravan's themselves come under general regulations...

Regulation 522.6.101 - read that carefully, and understand the dynamics of a caravan you soon realise that disconnecting the RCD for a main switch in the caravan its self is a non-starter.

For testing purposes, you literally have to bypass the outside rcd Temporarily.

Taking 1 of the RCD's out of circuit permenantly, is just not possible. Meaning, that you'll have to contradict regulation 314.1 - just one of them things.

 

[Engineer54]

Ahh Caravan's the strange world.

Regulation 314.1 requires the prevention of nuisance tripping - i hear alot of people doing away with the RCD's inside the caravan...

Now, lets look at section 708.

Regulation 708.553.1.12 states that the outside distribution box (to the caravan pitch) must have a RCD protecting the commando.

Static Caravan's themselves come under general regulations...

Regulation 522.6.101 - read that carefully, and understand the dynamics of a caravan you soon realise that disconnecting the RCD for a main switch in the caravan its self is a non-starter.

For testing purposes, you literally have to bypass the outside rcd Temporarily.

Taking 1 of the RCD's out of circuit permenantly, is just not possible. Meaning, that you'll have to contradict regulation 314.1 - just one of them things.

Just one of the many instances where BS7671 basically contradicts itself!!

 

[scammell man]

why is that nuisance tripping (assuming that is the contradiction you are referring to). In Caravan parks you need 1 RCD per outlet (read per commando socket). That you have a second RCD in series without discrimination does not equal nuisance tripping it just equals a race for which goes first.

 

[markc123]

why is that nuisance tripping (assuming that is the contradiction you are referring to). In Caravan parks you need 1 RCD per outlet (read per commando socket). That you have a second RCD in series without discrimination does not equal nuisance tripping it just equals a race for which goes first.

1 RCD per outside distribution box. The second is inside the static caravan it's self - which don't come under the special locations.

2 RCD's in series does equal nuisance tripping...especially when testing. 99.9% the outside will go before the inside, then leaving Mr.X unhappy at having to go outside in the piddling rain.

And you can't even upgrade the outside to a time delayed RCD either unfortunatley.

 

[scammell man]

that's not nuisance tripping, fault seen, RCD operated as intended, just no discrimination. nuisance tripping is taking out additional circuits or operating when no fault.

 

[bks]

thanks all

 

[markc123]

that's not nuisance tripping, fault seen, RCD operated as intended, just no discrimination. nuisance tripping is taking out additional circuits or operating when no fault.

Now we're been picky with technical wording. Suppose you're right, in a way...

RCD goes outside and takes all circuits out inside, so if it was a split-load board (very rare in static's) then it'd warrant nuisance tripping...

Common set up in caravans is a small 2/4way board inside the static - so yes, this doesn't warrant nuisance tripping as everything off 1 RCD - but in some, especially lodges you have 17th ed boards .... rcd trips outside = nuisance tripping.

 

[Lucien Nunes]

A bit late to the party here but why do you have to bypass the outside RCD for testing? Why not use the supply-side N for the 3rd lead of the RCD tester when testing the inside one? Then there's no residual current to trip the outside one. And of course the outside one can be tested without tripping anything else, unless some spoon has connected another RCD further upstream...

 

[scammell man]

Now we're been picky with technical wording. Suppose you're right, in a way...

RCD goes outside and takes all circuits out inside, so if it was a split-load board (very rare in static's) then it'd warrant nuisance tripping...

Common set up in caravans is a small 2/4way board inside the static - so yes, this doesn't warrant nuisance tripping as everything off 1 RCD - but in some, especially lodges you have 17th ed boards .... rcd trips outside = nuisance tripping.

ummm, not sure if you have a static that connection via a commando with an external RCD power pillar is appropriate. However, if this IS what you have a dual RCD consumer unit is clearly inappropriate for the reasons given. If you really wanted to go down this route you should be finding sub 30mA RCDs to go in the internal consumer unit. That'll get your local wholesaler scratching his head...