Message Forums

Quote: Originally posted by saxo1 on 15/2/2019

---

Morocco distribution system is an earthed system so should have an earth at the hookup point.
How do you test that there was no earth at the other posts?
Isolating the breakers in the van only isolates the equipment in the habitation area of the van.
The RCD on the post isolates the supply between the post and the distribution unit in the van(the hookup cable,the cable entry socket on the outside of the van and the short length of cable inside the van).
If there were a fault between live and any earthed part of the van on the incoming side the RCD on the post should trip.
I would check the earth continuity of your hookup cable,even if it is faulty the RCD on the post should trip.
saxo1

---

Quote: Originally posted by morepints on 15/2/2019

---

Live connected to earth at supply line?!!

---

Quote: Originally posted by navver on 15/2/2019

---

1. Possible live neutral cross at site post and neutral earth cross in EHU lead would effectively connect live to caravan chassis.

2. EHU lead earth conductor broken or pulled out of terminal.

For both the above, if the van has rubber tyres and plastic pads under steadies etc in dry conditions, there may not be enough live to earth current flowing to trip site RCD.

Very worrying though and it does need urgent checking as others may also be affected.

Did you have bare feet at the sites where you had no problem. It's surprising just how well rubber soled shoes prevent electric shocks.

---

Quote: Originally posted by navver on 16/2/2019

---

Somehow you've got live connected to your caravan chassis.

Your caravan is wired with the earth in your consumer unit connected to the chassis. This is standard practice and necessary.

Somehow the wiring in the site point has live connected to the earth core in your EHU lead. This earth core does not go through the RCD in your van in any way as it has no need to. It will make your chassis live waiting for you to touch it no matter what your RCD is set to.

---

Quote: Originally posted by Bob61 on 17/2/2019

---

Have you contacted the campsite to tell them so that nobody gets electrocuted?

---

Quote: Originally posted by ericmark on 17/2/2019

---

If as I suspect fault is in another caravan on the site, if you returned to site likely now no fault apparent. Although clearly the site has outlets without RCD protection.

We are told an earth rod needs 300Ω or less to ensure it has a connection and will not dry out, but with a 30 mA RCD to ensure no more than 50 volt above true earth 50/0.030 = 1666Ω which you could likely get from a tent peg.

If a RCD has become insensitive i.e. faulty then it would not need that much of a fault to cause the earth to become live, with no RCD on a 16A supply you would need an earth loop impedance of 3Ω to ensure the MCB tripped. To get 3Ω you would need a TN supply which in UK is not permitted on most sites as the supplies are normally TN-C-S to the site, and only where a TN-S supply is guaranteed can you use a TN supply.

In UK the step down transformer has to have an earth rod better than 15Ω so even if site earth rod was zeroΩ you could still not guarantee it would trip.

So even on a UK site, we rely on the owner doing a test of all outlets to ensure the RCD works. In theory there is no point having a RCD in the caravan, as all sites should have a RCD on the supply anyway, however it is possible the site was laid out before the point when RCD's were required, my earliest version of BS7671 is 2004 when RCD's were required.

In UK there is no need to rush out and update installations when a new BS7671 is issued, in fact there is no legal requirement to follow it. However if you don't then if there is an accident then it can be used to show one did not take reasonable care.

So if a site was laid out in 1990 to 15th edition wiring regulations with ELCB-v fitted, there is nothing to say they must upgrade. As how one would today test an ELCB-v I really don't know? Today we use ELCB-c so modern test gear would not work with old units.

The old unit introduced a resistance into the earth and relied on no earth after the device, so if you connect the leg steadies to earth supply and wind them into the grass they would reduce the chance of a ELCB-v tripping, which is why their use was discontinued.

Problems with earthing is not only with caravan sites, I have found whole houses without an earth.

Because in Europe line and neutral may be swapped we really do need a plug in tester, with a loop test if possible, however since using an earth rod as long as the 500Ω light is on that's good enough.

One would also need a 16A to 13A adaptor to test before plugging in caravan. However with a ELCB-v the plug in tester would always show fail even if it was A1.           

---

Quote: Originally posted by KarlFritz on 17/2/2019

---

Quote: Originally posted by Bob61 on 17/2/2019

---

Have you contacted the campsite to tell them so that nobody gets electrocuted?

---

They were advised of the 'problem' in 3 Languages (English, French & Arabic) at the time it was found.

Nothing had been done as we left 48 hours later.

---