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Posted By: pauluk Mobile home meter - 04/09/04 11:26 AM
I went out yesterday to run power out to a 28 ft. mobile home which has been located in a backyard for an eldest son to use.

It came from a nearby campsite at Happisburgh, where it appears individual meters are installed in each caravan.

The standard of wiring leaves something to be desired. The original SWA (armored) supply cable was just cut underneath, so this is exactly as the service had been operating:

[Linked Image]

Meter removed with old connections intact:
[Linked Image]
[Linked Image]

(Sorry about the lousy quality in the first photo. My cheap digital camera has no flash and doesn't handle dimly-lit areas at all well.)


[This message has been edited by pauluk (edited 04-09-2004).]
Posted By: Trumpy Re: Mobile home meter - 04/09/04 08:53 PM
Paul,
I gather that the Incoming main is on the left side?.
Also, you mentioned above that this is SWA cable, is there an actual connection between the Armouring on the Main and the Earth wire to the Consumer Unit in the picture?.
Metering of these supplies sounds like a good idea, over here the Customer pays a flat Tarrif in a Caravan area and the supply is un-metered.
However, the fusing that I've seen feeding these installations tend to be rather conservative.
I've replaced many a fuse because Mr and Mrs Holiday-maker tried to boil the jug with the 2 bar heater and the TV on.
BTW, Paul, is RCBO protection required in your caravans in the UK?.

{Just as a small aside Paul, I know what you mean about these mini-cams, although mine has a flash, using it can ruin a perfectly good picture.
The most infuriating aspect of this is, you don't know what the pic will look like until it's on the computer screen!.} [Linked Image]

[This message has been edited by Trumpy (edited 04-09-2004).]
Posted By: Bjarney Re: Mobile home meter - 04/09/04 09:50 PM
Offhand, the lower-side wiring looks identical to meter "A-base" connections in North America, including line/load, hot/neutral(hot) positions where 2-wire 120V (or 3-wire 240V) service is needed.

To accommodate socket and hardwired meters, the are adapters like those at www.geindustrial.com/products/brochures/GEA-9141.pdf




[This message has been edited by Bjarney (edited 04-09-2004).]
Posted By: pauluk Re: Mobile home meter - 04/10/04 09:00 AM
Scott,

Yes, the "A-base" as you know it is still the standard meter connection here, and this is the typical 2-wire single-phase mechanical meter, as used almost everywhere before digital types started to replace them.

Terminals are L-N-N-L, line to the left, load on the right:
[Linked Image]

Both the terminal and main covers have screws which can be secured with a wire and lead seal. A couple more shots with the main cover removed:
[Linked Image]
[Linked Image]

Trumpy,

No, there was no connection onto the cable armor. The 'van end was just hacked off to connect to the meter. Whether it was earthed at the supply end, I couldn't tell you.

As is typical in caravan installations, the unit was wired for TT earthing with its own earth rod. In the first photo you can just about make out the main earth lead to the left of the supply cable going into the distribution panel. The use of TT necessitates RCD protection anyway, and there's a 30mA device in the panel.

That panel isn't the original, by the way, as it's much too new for the age of the 'van. There was proper bonding to chassis and pipework in place, but the clamp which was on the old earth rod was very badly corroded. About 6 inches back from it, I also found a tell-tale bulge under multiple layers of black PVC tape. Sure enough, the earth lead had just a twist-&-tape splice there, which itself had already corroded badly as well (the site this was on overlooks the beach and sea).

Some sites here operate fixed electricity tariffs, others meter it separately. As these holiday-homes use gas almost exclusively for space/water heating and cooking, a 16A hook-up is quite normal.

By the way, this unit now has a 30A feed to it with the new cable terminated directly into the panel with a proper gland. [Linked Image]
Posted By: Trumpy Re: Mobile home meter - 04/10/04 10:21 AM
Paul,
I wasn't looking to be "smart" or smug when I made those comments.
But, over here, a caravan is called a Connectable Installation, also of the Mobile type.
This is why there are no Regulations here for caravans that are in one place for more than 6 months.
There are heaps of people that drive around NZ in a camper van, but never stay in any place any longer than a night. [Linked Image]
Posted By: Bjarney Re: Mobile home meter - 04/10/04 04:06 PM
There is one minor aside about electromechanical watthour meters that might become an issue if you are involved in submetering, or possibly installing a temporary induction-disc meter for energy/power logging of a specific load. To be accurate, the disc should be level in both planes {within 4° by ANSI.} Some years ago I learned this the hard way.




[This message has been edited by Bjarney (edited 04-10-2004).]
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