Really confusing old caravan electrics...

[Matthew_374540478]

Well I'm really excited - I picked up my new caravan... my first caravan... today. An old... maybe early 80s Swift Corniche 12/2. I towed it home 120 miles and it went and braked really well!! It only cost me 1 couple of hundred quid, so even if it did one holiday I'm quid in!

There are a couple of electrical issues internally however...

The previous owner told me that the electrics worked like this:

1. The 240v plug in works the fridge and two sockets... Presumably this old van never had proper 240 volts when new?

2. Two small spot lights are worked by a battery under the seat.

3. EVERYTHING else including the water pump, gas starter for the fridge, cascade water heater starter, gas fire starter, five main lights etc are worked by power from the secondary hitch conection to the car...

Now so far he is right on the 240 plug in stakes, but can't check either other power source as my car only has single conection at the moment, and the battery is obviously flat.

So, my question is, is his assessment of how the electrics are supposed to work correct? It seems a stupid system to me... I mean everytime you want to have water you'd have to plug the bloody car into the electrics!!!

I think what he has experienced is a flat battery under the seat... this would fit in with his experience, ie no power when the car is not attatched? Seem feasible?

I think what I should do is buy a caravan 12volt transformer / charger and wire that into the mains board and attach all the 12 volt electrics into that including a new leisure battery... good idea you think?

Is there anybody round Stockport or Manchester who would fancy coming round and having a look for me?

Thanks, here's hoping!

 

[forestgump]

some older vans had a inverter not a charger.go this way its cheaper and works ok

 

[Matthew_374540478]

An invertor... does that mean it simply changes the 240 to 12 volts? It wouldn't charge the battery then would it? So only 12 volts when plugged in?

 

[Damian]

Matthew, old vans had little in the way of electrics, so my guess is that it has all been retrospectively fitted, and at the time due to lack of suitable chargers, or personal preference, the person wird up the 12v in the way they did.

On modern vans you should have 12v available from the on board battery and it being recharged by a suitable charger (any of the now common 3 stage chargers will do fine)or a dedicated Power Supply Unit (Like the Sargent PSU2005)but these are not cheap.

The secondary connection to the car, the 12S, provides power for the fridge(12v) when on the move, and a charging circuit for the leisure battery, again when on the move.

It would be sensible to start the whole wiring setup again, taking each 12v appliance (pump, lights, fridge ignition, water heater control supply) through its own separate fuse from the battery or PSU with battery backup.

It is not a job to attempt if you have no real undestanding of electrics,as correct cable sizing is very important, especially with 12v as the amp draw can be very high, ( a 12v 20w bulb for instance will draw 1.6 amps but a 230v 20amp bulb will only draw 0.66 amps)

If you want to get an idea of cost, you could give one of these guys a ring and ask them to have a look for you:

http://www.mobilecaravanengineers.co.uk/mcea-find-an-engineer.htm
Lok for one local to you.

 

[Matthew_374540478]

Thanks for that - I might givem them a try. However, I think I'll buy a leisure battery first and just see, when attached, what works and doesn't :0)

 

[gary]

Without knowing it's actual age it's difficult to be sure, but the Corniche is 'top of the range' so by the 80's I'd expect a decent level of spec, including mains and a charger of some sort as standard.

A good clue is how neatly it's installed, if the wiring is tidy following straight lines and well fastened down? then probably standard or at least installed by someone who knows what their doing.

If however the wiring resembles spaghetti!! I would get it checked out before connecting anything to mains or a battery for that matter.

 

[Matthew_374540478]

Ha ha - yes spaghetti! Oh God I've bought another shed...

 

[Matthew_374540478]

Oh, and another question related to this post: if I fit a standard trickle charger to the battery, would I have to remove the 12 volt caravan wiring conections whilst it was charging? Cos' otherwise the 12 volt system would be getting 24 volts wouldn't it? Or am I wrong? Would something like this be better do you think:

Ebay number: 150408925852

Thanks!

Actually for 2 hundred quid I haven't been done... the parts are worth more than that alone, and if I have one decent week away it has been worth the money... but would love to get her working well again... I'll also need to do something about the rotten floor by the door... but, electrics first!