Cigarette Lighter Plug in Voltmeter Q

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Polarsilver
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Cigarette Lighter Plug in Voltmeter Q

Post by Polarsilver »

Winter due & not that happy to leave my cars on long term trickle charge .. so maybe another solution as my cars are fitted with a Cigarette Lighter socket .. To buy a plug in USB Adaptor Plug that comes with a Digital Voltmeter .. so this should give an of idea the cars 12v Battery state.. any ideas or experiences that will show the Battery Voltage at a glance with one of these plug in voltmeters ?
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by mk1 »

A good solution is to connect your trickle charge to the battery as usual, but then plug that into a cheap plug in timer, the sort you use for turning lights on & off when you are on holiday.
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Set it to come on for an hour or so each day & hey presto, you have the ultimate battery conditioning set up.

Any battery will be right as rain with a set-up like this indefinitely. It'll stay fully charged, but won't be damaged in any way.
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111Robin
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by 111Robin »

I run several CTEK battery conditioners year round and the cost is negligible. Once the battery is at full charge the current required to maintain battery condition is very low. I don't turn my house heating on until the depths of winter so in traditional Aberdonian style I am a grippy b*****d so if I can run these year round then they must be cheap :)
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by AndyPen »

I use a CTEK that came with my Aston Martin - brilliant bit of kit ;-)
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by timmy201 »

I’ve got one that plugs into a 12v socket kind of like this. You do need the ignition on, so up to you if it’s more or less convenient than a multimeter
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If you are concerned with charging the battery in the car you can always remove the battery and charge them away from the car, even just one day a week/fortnight
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by Spider »

I found one of the best things to keep a battery good when laid up is to disconnect it, just one terminal is enough. It will still go flat over time but will go for very long periods, I've found 6 + months, before needing a charge or top up. The other thing that's easy to over look is to be sure the battery is clean. If it's dirty or dusty, this will cause some leakage between the terminals.

Inevitably, there's some leakage, small as it might be, through the car's system, especially if an Alternator is fitted, along with all the usual accessories we fit these days - the radios with clocks and station memory, the USB sockets, clocks and other stuff we seem not to be able to live without these days all draw power.
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by snoopy64 »

I have the ctek charger and use a timer socket like Mark suggests..1hr week does it for me… the one thing I do know is once a battery is flat it’s never the same again!
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by MiNiKiN »

I have one of them cheapo chinese lighter plug voltmeters in my Vespa, where it is working in anything but favourable conditions, and it has been working like a treat for many years. If you have your fag lighter connected to permanent plus (which you have to to use it as a charge point) it will show the voltage (and of course drain your battery). Anyway, voltage is not the best indicator of the charge state. Open-circuit voltage of a lead battery is pretty constant over a long period of time, once it drops noticeably the battery is usually very low on charge already.

I'd use a trickle charger or as Mark wrote a charger connected via a timer. The absolute battery killer is the combination of an empty battery and temperature below 0. So trckle charging in an unheated garage is essential for battery longevity.
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Re: Cigarette Lighter Plug in Voltmeter Q

Post by nick@dunsdale »

I have a quad that i use for towing a grass cutter
It gets laid up around now till spring
I just disconnect the battery and it will still start the quad come the spring time been doing that for the last couple of years
If i remember i will put the multi meter on it in the spring to see how much it has dropped over the winter
The best repairs go un-noticed
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