I'm thinking of building in one of those Lidl battery chargers in the old car. So it can be left on float when not in use. The mains lead on those is only two core and the case plastic. I was considering a Buccaneer weather proof mains connector mounted in the body below the rear bumper. Should the car body be connected to mains earth?
No. If the battery charger is double insulated, then the only issue is preventing the chassis becoming live from a fault on the mains cable. Cover the mains lead in plastic conduit and ensure that it can't chafe or snag on anything. Make sure you plug in to an RCD-protected supply.
Dave Osborne gurgled happily, sounding much like they were saying:
Or do it the other way round, and plug the low-voltage into the car, keeping the charger.
Motorbike Optimate-style.
How about "dodgem car" style.
Park one wheel on a metal plate and some kind of ceiling contact. Ground the plate as well.
I've got no idea how many ohms a tyre would present in circuit...but surely a small enough figure to trickle charge a battery?
That's what I have done.
My Halfords 'maintenance' charger came with both croc clips and also a set of flying leads that could be permanently bolted to the battery terminals with an in-line shrouded connector that matches the one on the charger. So to do a trickle charge, I simply open the bonnet and quickly hook up the flying leads to the charger. A red/green led indicates when the battery is fully charged.
David
This is actually something that was covered in the most recent edition (17th) of the wiring regulations, in relation to power hook-ups in caravans and motorhomes.
Basically the regs say that caravans and motorhomes must have metallic bodies/chassis earth bonded, along with RCD protection on the hook-up.
Presumably the reasoning behind bonding is that should there be a fault that caused the body to become live, it could present the most dangerous scenario of someone barefoot outside the vehicle touching live bodywork.
That's all well and good in places like UK campsites with properly tested hook-ups that have both a good earth and RCD protection.
It's not so good on places where there's a dodgy earth, or the possibility of live/earth being transposed.
So - practically - do what you feel is safest in the locations you will use your charger hook-up. Not bonding and carefully protecting the cable sounds reasonable, if you're the only user and use it in locations you trust.
An approach popular with many van users is to use a "tent power hook- up". This is basically a mains plug on one end (often a commando) and a mini-consumer unit on the other.
e.g.
On untrusted locations, one of those mains test plugs to check polarity of the wiring and the presence of some sort of earth, is a cheap and quick way of getting an indication that all may not be well.
The extra-low voltage option would be by far the safest solution. If you really do want to put a 230v mains supply into the car then use a
3 core flex with a trailing socket and a 3 pin mains rated connector at the car end. Earth the car via the earth pin of the connector. Also use a supply with 30mA RCD protection (which all sockets rated at less than 20A, intended to supply equipment for use out of doors should have for additional personal protection in the event of a fault)
Voltage drop in the cables screws with measuring float voltage. Where this is done commercially, it's a 4-lead setup back to the sense input.
FWIW, engine block heaters and battery conditioners are *very* common in these parts - I'm not aware of any of them typically being grounded, but then they always seem to have a little bit of trailing flex and socket, rather than a socket mounted rigidly to the vehicle's body.
(I'm not sure how well a cheap battery charger will stand up to permanent connection and repeated starts with it connected? I expect - but don't know for sure - that a proper conditioner is designed to be a bit more robust in that regard)
cheers
Jules
The Lidl charger is only cheap in price. It's an extremely sophisticated design. Those 'proper' conditioners are often a con price wise - for what amounts to little more than low power DC supply with a few added components.
Thanks - that's what I'll do. Although I wasn't intending having any mains outlets in the car. ;-)
Rather guessed something like that would apply.
I'd rather a neater way. The charger will fit nicely in a dead space alongside the spare wheel.
Dave Osborne pretended :
I do it the other way around...
Lidl charger is in a bracket, up in the garage roof, with a 12v cable fitted with a ciggy plug dangling down to car. As I park, I pull the ciggy plug in and plug it in. The ciggy socket has to be the type which is on all the time, which depends upon the car.
That's fine if you have a garage...
I have wondered why that varies between manufacturers. Mine does, and it's very useful to leave a camera or phone tucked away and on charge sometimes.
snipped-for-privacy@gglz.com expressed precisely :
Better would be cars fitted with a switch so the driver could select how he wanted the socket to operate.
Vortex4 explained :
Several megs at least, so no.
Jules submitted this idea :
They (Lidl unit) will be fine. I have one in use like that for a few years. My car can at times sit in the garage unused for weeks, so it is often left with a Lidl unit connected. I have also had it charge flat batteries up and it gets no more than luke warm.
The only down side, is if the mains goes off briefly - you need to press a button to restart the charge.
on 16/12/2009, Dave Plowman (News) supposed :
Agreed, I have three or four of them. One permanently set up to maintain the car in the garage, one on the tractor, one in the caravan, and a spare around somewhere - with an Optimate keeping the bikes battery ready to go.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.