Caravan park installation

[bks]

Working in a caravan park as a full time electrician found that most of the hook up point in every single pitch got high Zs reading because of using two core SWA (average 1.7 ohms TNS earthing system). In some cases up to 31ohms because corroded SWA glands and broken SWA. if there's been used 3 core and you wouldn't have many issues with reliable earth for caravan.
now my question is; is there any Regs that contractors have to or must use three core SWA for all caravan park installation. Recently the park I work, all the caravan park installation under ground cable has been upgraded but 2core. I raised this issue to the contractor but never listened and said its fine. I know that SWA can be used as earth but no good for long term due to weather and could corroded glands and SWA then loosing earth continuity or not reliable earth. In many cases I had to replace SWA glands or re-terminate while doing EICR for those caravan.
What do you think guys using 2core SWA in caravan park and in this typical English weather?

 

[Plonker 3]

Section 708 of the BGB will help you.

As for the glands is there any bonding in the caravans?

Also if the correct gland is used and terminated correctly then they shouldn't corrode.

 

[davesparks]

Sounds like either the wrong glands used, or the right glands not terminated properly to me.

Normally 2 core is absolutely fine. And even if 3core is used the armouring still needs to be earthed and terminated properly and protected from corrosion.

Good quality C or E type glands properly terminated are what you need.

 

[SirKit Breaker]

Section 708 of the BGB will help you.

As for the glands is there any bonding in the caravans?

Also if the correct gland is used and terminated correctly then they shouldn't corrode.

I agree, and a good look at part 5 is also a must. Then some familiarity with external influences (Appx 5 i think). In our climate, and all manner of people using caravans then this has to be bang on in my opinion.

Cheers.............Howard

 

[Engineer54]

The problem comes if or when the supply to this caravan park is PME'd!!

Personally, for a caravan park i would have gone for 3 core SWA cable. Depending on the distribution method, the armouring may not comply if distances are excessive, and won't comply where permanent mobile homes are concerned for bonding purposes!!

 

[atm84]

Shouldn't caravan hooks up be TT supply?

 

[driverman]

Shouldn't caravan hooks up be TT supply?

Yes All hook ups to Caravans should be TT
the Distribution wiring can be Tn though , as long as split and made into TT at hook up point or fixed connection point if static caravan

 

[Doomed]

TT or TNS, never TNCS.

Several parks I test have the same issues, have been having to regland on a regular basis.
One of the main issues is condensate over the winter period corroding the locking ring.

One small site ended up putting a stake in at every hook up (and separating the other earthing arrangements).

The sites that back their hook ups over the winter seem to have more issues then those that don't - the bag retaining moisture during dry periods?

I live by the sea, and the salt air doesn't help things.

Don't get me started on the marina hook ups.....

 

[atm84]

Sounds like caravan sites make good customers- plenty of work from them.

 

[driverman]

Yes All hook ups to Caravans should be TT
the Distribution wiring can be Tn though , as long as split and made into TT at hook up point or fixed connection point if static caravan

A lot of problems is brass glands being used with galvanised locknuts! Should be brass

 

[Andiwoo]

I've been working a lot on a static caravan site which is TNS, for the past few months now and I have had the same problem with terminations being badly corroded and also not installed properly giving me a terrible earth or no earth at all, although for the ones that are terminated correctly and not corroded I do average around 0.6 to 1.3 ohms for Zs/zdb at the hook ups. I don't like the fact that you rely solely on the sheath for your earth, I think they should have to run a 3 core to hook ups. I have also pulled swas out of their glands at hook ups. I also thought before I started here that you had to TT every van but this apparently is not the case for TNS on static sites.


It's also the loop in loop out method so 6 or 7 caravans are fed together so when you have to work on 1 hook up you have to upset a whole bunch of people that don't realise they're on holiday and should be out during the day, I literally had one shout at me that they're missing Jeremy Kyle and for a second I thought it was a joke. On that note if the first van loses its earth because of a bad termination then all on that line lose it as well. This site is right on the sea edge so open to all the sea elements which destroys everything over time. Caravan sites are a nightmare end of.

 

[Carlosfandango]

Sounds like caravan sites make good customers- plenty of work from them.

I've popped into a few local caravan sites and given them one of my cards only to be told, in a rather patronising way, that all their electrical work is done by the maintenance men!

 

[Fin170]

I don't like the fact that you rely solely on the sheath for your earth, I think they should have to run a 3 core to hook ups.

But if they had used 3 core, would you have picked up that the armour had been poorly connected? :smug2:

As above, it's irrelevant how many cores you run as the armour must still be mechanically and electrically sound.

What do you think guys using 2core SWA in caravan park and in this typical English weather?

1) More likely to win you the job than specifying hundreds of pounds worth of unnecessary copper 2) Most of the cables where I am now are in excess of 50 years old, 9/10 using the armour as cpc and I've not found any where the armour is giving a poor connection*. With that In mind Im not worried about utilizing armour as cpc because I don't think a properly made of cable is any more unreliable than a bit of wire in a screw in connection

*Other than the very old SWAs where there is no outer sheath, unsurprisingly, thats useless

 

[Paul.M]

I did a caravan hook up install a few weeks ago working for an "old forum friend (cough)" and we did belt and brasses, earth rod at each point + using 3 core and the swa as main earth for only 2 pitches at a time. Bullet proof install for the price of a few more quid per point. We both looked at section 5 and came to the same conclusion, £10 in parts and an extra 15mins in time, it's worth it.

Top job working with/for a Top Sparky. (D/S)

 

[Andiwoo]

Well thankfully I have a good habit of checking swa connections so yes I do think I would pick it up to be honest. Also I think you misunderstood what I was saying, I know the swa has to be well terminated whether it's the main earth or not. I'm saying that you rely solely on this being a good connection because it's your only earth and I have come across a lot that have been badly corroded and poorly connected. So with 6-7 vans relying on van 1 to have a good armoured connection is not good. I have personally had 1 poor connection on van 1 which lead to there being no earth on all the other vans on this leg, I found this by having to test a van that was second to last on the line. Now if this was a 3core the chances of there being an earth on that last van is a hell of a lot higher. I'd take a copper connection inside a hook up box over the armour any day, to have both is an added bonus.


The second quote you tagged me in was actually quoted by the original poster, but to call it unnecessary copper doesn't seem quite right to me, from what I've personally seen and I think whoever got a belt off a live van and suddenly became the vans earth rod would strongly disagree with you.


Either way it's each to their own but I personally don't like the set up and would rather see an additional core or a TT point at every van. The cost on this site would be extreme as it's a very big site but safety first eh.

 

[davesparks]

Poor termination is not a result of it being 2 core though is it?

If the outdoor conditions are that bad then take the SWA through a stuffing gland on the enclosure and terminate to an internally mounted gland plate/ lamppost gland plate type of thing!

 

[Meggerman]

Well thankfully I have a good habit of checking swa connections so yes I do think I would pick it up to be honest. Also I think you misunderstood what I was saying, I know the swa has to be well terminated whether it's the main earth or not. I'm saying that you rely solely on this being a good connection because it's your only earth and I have come across a lot that have been badly corroded and poorly connected. So with 6-7 vans relying on van 1 to have a good armoured connection is not good. I have personally had 1 poor connection on van 1 which lead to there being no earth on all the other vans on this leg, I found this by having to test a van that was second to last on the line. Now if this was a 3core the chances of there being an earth on that last van is a hell of a lot higher. I'd take a copper connection inside a hook up box over the armour any day, to have both is an added bonus.


The second quote you tagged me in was actually quoted by the original poster, but to call it unnecessary copper doesn't seem quite right to me, from what I've personally seen and I think whoever got a belt off a live van and suddenly became the vans earth rod would strongly disagree with you.


Either way it's each to their own but I personally don't like the set up and would rather see an additional core or a TT point at every van. The cost on this site would be extreme as it's a very big site but safety first eh.

I agree. 3 core and having a dedicated cpc is far better. Far less likely to lose earth to vans which is most important fact and 50% less likely to lose earth connection to sheath as it has earth connected both ends by cpc core.

 

[davesparks]

And if it is installed properly with due consideration to the environment it is in then no armour connection will corrode anyway.

 

[Meggerman]

But in reality it has failed, and others do too. I earth the sheath but always use dedicated cpc. Except out to my garage where I inherited the old 2C 2.5 SWA .

 

[Plonker 3]

Poor termination is not a result of it being 2 core though is it?

If the outdoor conditions are that bad then take the SWA through a stuffing gland on the enclosure and terminate to an internally mounted gland plate/ lamppost gland plate type of thing!

You have basically described a CW gland which should have been used here anyway.