Another RCCD Tripping

[pjelec]

Back again with another problem and I had great help from my last Thread.
I am currently working in Spain and have a problem on a caravan site. There is a mains board installed in between 20 caravans which supplies each caravan. In the mains board there is a 20amp Circuit Breaker and an RCCD feeding each Van. The cables are in tube 3 x 6mm. Once into the van it feeds a fuseboard, In the fuseboard are all the circuits for the van all proteced by another RCCD in that board.

6 of the vans keep tripping their own individual RCCD in the outside board. Never does the internal one trip out. On 1 van i replaced the cables from the box to the van 10 metres and the problem is still there. I have tested all cables and have a reading of >999.

Very starnge ther other day at 0800hrs one resident went to switch her RCCD back on in the outside box and was met by another man doing exactly the same. They tripped out at the same time. This was not the first time either.

We do know that the voltage here is not as stable as the uk it varies from 200v to 250v.
I did remove the RCCD in the outdoor box for 2 weeks and the internal one did not trip out once. I have now reconnected it and its tripping again.

The RCCDS are GE 30ma 40amp.
I just can not come up with any more ideas
Hope someone can help.

 

[mark80]

Well it sounds like you have 2 RCD's in series. As in one protecting the cable to the caravan and 1 in the fuseboard in the caravan. This is not needed and will cause nuisance tripping.
Either take the RCD out of the CU in the caravan or for ease of resetting for the people if it trips, remove the 1 from the main CU. Is it SWA going to the caravans??

 

[pjelec]

Spanish rules here says you must have an RCCD in the van and an RCCD at the source. The site will not allow me to remove the one outside. SWA is not used here, so the mains are in metal flexi tube. I do agree about 2 RCDs in series but if i remove the one in the van then the one outside may still trip out.

Well it sounds like you have 2 RCD's in series. As in one protecting the cable to the caravan and 1 in the fuseboard in the caravan. This is not needed and will cause nuisance tripping.
Either take the RCD out of the CU in the caravan or for ease of resetting for the people if it trips, remove the 1 from the main CU. Is it SWA going to the caravans??

 

[mark80]

Well if they are the same rated RCDs then you have no discrimination. Can you not fit a time delayed RCD at the source?

 

[pjelec]

This is something I came up with but when I asked our Spanish Engineer if we could, we were told that it does not comply with Spanish Regulations. Fighting a loosing battle in Spain

Well if they are the same rated RCDs then you have no discrimination. Can you not fit a time delayed RCD at the source?

 

[Guest123]

Are the vans on TT out there???

Have you tried a ramp test to establish the tripping current of both RCD's, also a mA clamp meter to detect any earth leakage present???

 

[pjelec]

We are limited to what testers we have here. We do nt have either of these testers

Are the vans on TT out there???

Have you tried a ramp test to establish the tripping current of both RCD's, also a mA clamp meter to detect any earth leakage present???

 

[Guest123]

We are limited to what testers we have here. We do nt have either of these testers

Ah. Fault finding without test gear, not good.