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MG Midget and Sprite Technical - Voltage drop?

Hi,
I have a smart charger and recently installed a cigarette lighter in the live circuit of my frogeye so that I can charge or trickle charge the battery by simply plugging it into the cigarette lighter socket.
That was working well, but recently it seems to have been working a little erratically and today cut out completely. I have used quite a long piece of cable running in the stepped down 12 volt section from the charger to the cigarette lighter socket. It is about 20 to 25 foot long I would guess. Could it be that I have too much flex and I am getting a voltage drop which is causing the problem, or is that just plain stupid?
Sorry if that's a daft question, I spent most of my physics lessons looking out the window!
Thanks
Graham M V

The current is quite low from a trickle charger, so the long wire ought not to be an issue.

Perhaps there is an issue with the wiring from your lighter to the battery.

Norm


Norm Kerr

In my experience cigarette lighter sockets that have been used to light cigarettes tend to have crud inside and hence poor connections. f you've recycled a previously used socket it might be worth giving it a clean out with a small wire brush.
Growler

Thanks for input. The cigarette lighter socket is brand new, and I am certain it's wiring is ok.
Another daft question. Could the cold weather here have an impact.
If not I can only assume my charger is faulty. Sods law. It is just out of warranty
Graham M V

could it be a contact problem with the plug and/or socket perhaps not fitting together well or poor connection of wires to plug or a small bit of muck/crud on plug

if you're in Middlesex I doubt it's the cold as I lent my (Carcoon badged) Accumate battery conditioner to my neighbour a couple of winters ago and it went from my very cold shed to his equally very cold garage when the outside temperature was well into the minus figures and when I first plugged it in it did flash a sequence of lights not mentioned in the handbook but with use it soon warmed up and settled to normal operation

when I used to use mine I had it wired directly to the battery via a fixed thin twin wire flex and very small plastic socket with the corresponding very small plug from the conditioner, from this I made a long power lead to plug into an outside mains socket, the battery conditioner sat inside the car which was outside during previous winters and it worked fine
Nigel Atkins

If your socket is fine, and the wiring is confirmed, then the next thing to try is directly connect to your battery to check that the battery itself is OK. Trickle chargers confronted with a battery that is too flat will shut off because they don't get enough feedback from the flat battery to tell them that they are even connected to it.

I have seen this before, and often a few minutes with a 2A, or 6A (normal) battery charger in place of the trickle charger will juice it up enough to get things working again when I re-connect the trickle one.

If it keeps happening, then I'd question the health of the battery itself, as they tend to start going on their way out after about 5 years. And, less than regular use (especially if they are then used when partially flat), will hasten that date.


Norm

Norm Kerr

Electronic racism ....

Copper colored wire hates silver colored wires and connection...put the 2 togather with some electric juice...and that Mis-spells electrolise ....

meaning you got a war on your hands, just like here in the mid west at the county and state fair 4H Vs. FFA (Future Farmers of America) esp. when it comes to judging a 3 year old sow..... Put those 2 gangs togather and i assure you, someone is going to spit some chew at someone and its lights out after that

Well thats my guess... Id also look at the various grounds and battry cable wires for the green powder of corrosian


Prop
Prop and the Blackhole Midget

Thanks. So generally opinion is that having a very long wire between the ring smart charger and the car should not cause a problem?
It seems to be working now. I am confident the wiring is 100% and there is an led in the cigarette lighter plug (male) that comes on without fail, that would seem to confirm it.
The battery is quite healthy. Even without using the smart charger, a few weeks back the car fired up immediately after not using it for several weeks.
I am guessing that maybe there was some condensation inside the charger, or else the charger is toast. It is a Ring charger.
Graham M V

don't think so but you could try long mains lead to the unit and short charging leads if you want to be sure

perhaps before the battery was fully charged or just the conformation light is just faulty

do check the battery for clean posts and electrolyte level in each cell just as a matter of good practice if nothing else

another thing to consider if the charger's connections are good and mains plug and fuse are fine then what about the supply cable or actual socket that the charger plugs into
Nigel Atkins

This thread was discussed on 18/11/2012

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