LG John

I'd like to know what is involved in running power to a permanently sited touring caravan approximately 50-60m away from the house. The cable itself needs to be suitable for shallow burrial to cross a narrow track but will usually just sit overground along the back of a wall where nobody/thing ever goes. At the caravan end it would have a standard blue 3-pin connector and at the house end I'd initially like to get away with a normal 3-pin plug so it can be fed through a window hopper and plugged into a standard wall socket. It would only get used for 2-3 weeks of the year and one or two weekends and would be unplugged the rest of the time. The cable however, would remain outside so needs to be weather proof. In the caravan it would usually only run interior 12v lighting, a built in mains/12v/gas fridge and a monitor/xbox when it's raining. We could accept it if we could only run one high load device (kettle, toaster, hair straightners, etc) at once.

I basically need to know what cables/connectors I require to do this and any other equipment/safety devices. Ideally you'll be able to suggest where to buy the gear as well. The caravan is mines and the house is the old man's. To convince him to allow me to tap into his power I need to be armed to the teeth with a full proof plan of exactly what I'll do and that it won't blow his power system; this is very important - he'll never agree to it unless I can convince him that it won't be any hassle to him whatsoever and won't damage his power systems. He'd simply hit the roof it I got it all hooked up and melted his wiring box by turning the kettle on or something.

Thanks

J4CKO

iTrader: (1)

SB, I buried a cable to my garden cabin, I dug the trench and the Electrician told me to take it down to 70 cm, armoured cable, with rocks on top and tape saying "Cables Below !".

LG John

I doubt I'd have to be so official in my burial methods as its a private croft and nobody would go digging there without our permission/knowledge. I've done some googling and found plenty of 25m long external weatherproof caravan/camping cables with a blue connector at each end. I'm wondering if I'd get away with plugging two of those together? Does anyone know what those actual cables are called (i.e. the wire) as it might be cheaper to buy 50m of the actual cable as those blue connectors are cheap as chips and presumable easy enough to wire up.

kingofturds

iTrader: (1)

3 core Swa cabled 75 cm deep if it's unpaved ground, although the 17th edition regs kick in soon so that may have changed. It would be better to go for a seperate mcb from the consume unit from the house with to a conume unit, and of course all part part p

LG John

all that again in laymans terms please k-of-t

c_maguire

If you wish to follow the correct procedures (and you'd be obliged to if you were installing this for a third party on their land) then this is going to involve a lot more arseing around than I expect you'd be happy with.
I would say in any case because of the track you mentioned and just general tidiness that you should use armoured cable ( 3 core x 2.5mm or you'll get away with 1.5mm ) and bury it say 30cms down minimum. If your old man has a power socket (preferably a double one) in a convenient position on the wall inside then you could open it and drill through to the outside. Then you can mount a waterproof switch-box on the outside wall and run a short length of cable through the wall. Effectively you have added an exterior spur to your old man's ring main. You can connect your armoured cable into the switch-box allowing the power to the van to be isolated if required. The circuit will be protected by the existing trip/fuse for the ring main inside the house ( 32 or 30 amp ) and also by the 30mA RCD device in the house.
The weatherproof cable you mentioned is likely to be just high quality flex for outside and just for temporary use like plugging a caravan into supplied power at a campsite for example.
Kevin

kingofturds

iTrader: (1)

You cannot really get away with a plug with 2.5 flex trailing from the house supplying the caravan, although it would work it would contravine every reg in the book and the volt drop may be a problem. Ideally you need to have a mcb from the house consume unit/fuse box supplying the caravan via a steel wired armour cable.

As an apprentice I have seen the aftermath of someone dropping a spanner ona 3 phase buzbar so be carefull ffs if unsure

LG John

Thanks for the responses so far Allow me to embelish the tale a little further:

Ultimately I aim to have a permanent armoured spur coming from the house systems with whatever seperate boxes/cutoffs are appropriate and with the cable burried to a suitable depth along the entire length from the house to the caravan. However, if I ask my old man if I can rip up 60m of the field, lay a cable, drill holes in the croft house and fit new boxes/systems he'll flatly say NO!

I get married this year in the area of the croft so my dad won't be working on it this summer. However, I know he plans to gut it completely within the next 2-3 years and that would involve extensive re-wiring and re-plumbing. My plan is to mastermind a situation where I have a temporary electrical hookup running for perhaps one or two summer seasons and hopefully at no inconvience to him (i.e. his box isn't tripping constantly, etc). That way when he comes to do the house I'll push him down the road of a permanent armoured cable as if it was his idea all along Hopefully this will give you some idea of what I'm trying to achieve.

To this end would I get away with one of these: Ebay Link. The guy can do it in 50-60m lengths for around £35-40 which is very reasonable and he said it's suitable for temporary outdoor use but it would be unwise to just leave it there permanently (in case it gets cut or chewed, etc).

There is a little rcd trip box in the caravan so I figure that would trip before the house mains if there was a problem. However, for added safety I could get one of those cables and perhaps plug it into one of these then into a house socket. That way surely either the caravan box or safety breaker would trip before bringing down the house mains. In case you can't tell, my dad would likely flip if he was watching the football and his circuit breakers went because I boiled a kettle

So, hands up if you think breaker+60m cable linked above would do the job for 2-3 weeks of summer?

c_maguire

It'll work. The cable is as I expected. If you go to Newey & Eyre or other electrical factor you could buy the cable off a roll to get one length without joiners. With flex outdoors you can buy PVC tubing (in 3m lengths with glued joiners) to protect it if required. B & Q supply the cable, fixings and connectors etc but the cable may only be in 25m lengths. If you use the tubing then you can be a little less choosy about the flex you use.
How are you going to 'plug in' at the house end?
Kevin

TopBanana

Yep it'll be fine.

mad555

iTrader: (1)

3cre 6mm SWA cable buried 700mm below the surface,bottom 100mm should be sifted sand then the cable lays on top of this,cover this with 150mm of sifted soil or sand,on top of this place a cable tile and then the rest of the 450mm fill with back fill.Connect this at the house to a seperate consumer unit with a 30mAmp RCD fitted with a 32A MCB.

sparkykev

I'd go down the flex route myself, you'll need rcd protection at the house for definate, an rcd adaptor or plug would suffice.
What you're doing isn't much different to running a hook-up lead on a touring park, except they usually limit leads to 25m long, but some are used for longer than a couple of weeks at a time.
I'd try and tack the cable off the ground where possible, and as said before, at vunerable places pass the cable through rigid plastic conduit.
If in doubt though, get it checked by an electrician.

LG John

Literally just plug it into the ring mains via a 13amp 3-pin plug. As I said this is designed to be a temp solution to last a few summers and will only be in place for a few weeks at at a time. Thanks for the advice re: rcd protection Kev. I note you can get rcd plug things for about £8-10 so I'll get one of those. When it comes to getting a permanent arrangement I'd likely contract in someone to do a professional install.

LG John

btw, if the 'voltage drop' (I'm quoting your terms here) is too great over this length of cable what would happen? Would appliances not work correctly or would there simply be no power at the caravan end? What kind of power draw do you think I could load onto a temporary 50-60m arrangement? The little fridge would be on all the time and perhaps 12v lighting. Think I'd get away with 20" LCD monitor and xbox 360?

c_maguire

Most of the stuff you're talking about running draws peanuts current anyway, it's only the kettle that could cause you problems. Modern 'quick boil' kettles are often around 3kW which is approx 10 Amps so if you're connecting using a 13 Amp plug and/or protecting using a 13 Amp trip then you'll have to turn off at least the TV to make the tea so you can have the lights on and see what you're doing. If you get a traditional kettle it'll halve the current so you should be OK.
Voltage drop is caused by the resistance of the cable. To reduce the resistance you either shorten the cable or increase its' diameter. So in your case you need to use the chunkiest flex you're prepared to pay for and cut it to the right length ( don't leave extra coiled up at either end ).
When I asked how you would connect at the house I was wondering how you intended to get the cable outside without drilling through your old man's windowframe or leaving the window open.
Kevin

LG John

Kevin, I'd just sneak it in through the top hopper in the back bedroom. In fact, the frames and house are so old I could probably take the plug off and find a hole somewhere large enough to feed the flex through