![]() | Home > Maintenance & Modifications > Battery dead but very warm- what do i do? |
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shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347 ![]() ![]() ![]() |
Awesome news
![]() What about the old battery though? Running Restoration Thread http://www.defender2.net/forum/post323197.html#323197 Self confessed mileage hunter ![]() |
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Cupboard Member Since: 21 Mar 2014 Location: Suffolk Posts: 2971 ![]() ![]() ![]() |
coils in the alternator ![]() A magnet (whether permanent or an electromagnet) spins inside a load of coils of wire. The coils are very tight and have thin insulation on them so can develop faults. The spinning magnet creates an oscillating ~ positive/negative (AC) wave centred on zero which isn't much good for charging a battery, so a collection of diodes is used in a rectifier circuit to make the "negatives" positive. A diode is like an electrical check valve, only allowing current in one direction. With just one diode you get just the positive humps (so half power), with 4 you can get the negative humps as well. Typically alternators have more than one set of windings so that as the power from one set is decaying, another is coming up to its peak. That way you don't get so much ripple. Edit to add: in a car, the magnet is usually an electromagnet. That requires current to flow through it in order to produce a magnetic field that then induces a current in the stator (the non-spinny-bit). Last edited by Cupboard on 22nd Dec 2014 7:51pm. Edited 1 time in total |
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K9F Member Since: 12 Nov 2009 Location: Bournemouth Posts: 9610 ![]() ![]() ![]() |
Read my post about possible battery regeneration 3 pages ago.....Or simply bin it.
![]() Treat every day as if it is your last....one day you will be right!! |
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shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347 ![]() ![]() ![]() |
Just gone out in the dark and had a look and everything is dark with not the faintest glimmer from anything on the dashboard.
Interesting didn't realise that ![]() K9F will have a read and make a decision ![]() Thanks again chaps! ![]() ![]() Self confessed mileage hunter ![]() |
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shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347 ![]() ![]() ![]() |
I will leave it on charge tonight so its had a full 24 hours to recharge, if it doesn't hold its power I'll drop it off at my local recycler.
I don't want to risk gassing myself or the dog or being splashed with acid - I have a good working replacement so if it doesn't hold charge its dead. Running Restoration Thread http://www.defender2.net/forum/post323197.html#323197 Self confessed mileage hunter ![]() |
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yostumpy Member Since: 01 Aug 2010 Location: n/kent Posts: 327 ![]() |
Ah but did you feel the new battery to see if it was warm? ![]() |
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jst Member Since: 14 Jan 2008 Location: Taunton Posts: 8336 ![]() ![]() ![]() |
What's the voltage across battery engine running Cheers
James 110 2010 XS Utility 130 2011 M57 bespoke Camper 90 2010 Hardtop 90 M57 1988 Hardtop |
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shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347 ![]() ![]() ![]() |
Just checked the battery and was same temp as rest of vehicle so all is well there.
Voltages are as follows: 12.64 - engine off, everything else off. 13.64 - engine on tick over , everything else off 13.80 - engine on revved then on tick over 13.45 - engine on tick over high beams on 13.50 - engine on tick over low beams on 13.14 - engine off everything off, voltage slowly dropping back to 12.64 Did debate testing the amps but I'm not sure my multimeter would take that kind of power. Running Restoration Thread http://www.defender2.net/forum/post323197.html#323197 Self confessed mileage hunter ![]() |
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dorsetsmith Member Since: 30 Oct 2011 Location: South West Posts: 4554 ![]() |
That looks good to my and your alternator 45 to 50 amps output to much amp of your multimeter 10 amps max
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Cupboard Member Since: 21 Mar 2014 Location: Suffolk Posts: 2971 ![]() ![]() ![]() |
to measure that sort of current you'd be looking at a clamp meter:
http://cpc.farnell.com/tenma/72-9480/multi...dp/IN06560 |
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munch90 Member Since: 26 Oct 2013 Location: guildford Posts: 3558 ![]() ![]() |
all looks about right ![]() don't test amps with your meter |
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shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347 ![]() ![]() ![]() |
Thanks chaps for all your help
![]() Self confessed mileage hunter ![]() |
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jst Member Since: 14 Jan 2008 Location: Taunton Posts: 8336 ![]() ![]() ![]() |
alt is all good then it seems. Cheers James 110 2010 XS Utility 130 2011 M57 bespoke Camper 90 2010 Hardtop 90 M57 1988 Hardtop |
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shaggydog Member Since: 12 Aug 2012 Location: Kent Posts: 3347 ![]() ![]() ![]() |
Seems to be
![]() Touch wood new battery seems to have cured it. Thing I notice most is the lights on the dash seem to glow brighter having changed it. Still, for now, mischief managed thanks again for all your help ![]() Self confessed mileage hunter ![]() |
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