Battery voltage - problem sorted!

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Ralf85
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Re: Battery voltage

Post by Ralf85 »

Ok guys. It's starting to get dark now so I am indoors.

Main battery charged for 20 hours. Left for 4 hours now the battery shows 12.91V connected to it's van terminals. Disconnected leisure battery completely. Choke set and engine started. Voltage across the main battery terminals shows as 13.73V on choke revs. Increased the revs to 1500+ and the voltage did not change. If anything it fluctuated down to 13.70V with increased revs. Switched engine off.

Checked voltage on the leisure battery - it showed 12.66V. Connected up the leisure battery and started the engine again. Voltage across the terminals with engine running 13.69V. Increase revs again and there was no increase in voltage. I have not checked the amperage. Is that sufficient to identify the problem or do I need to do more? Cheers.
:?:

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AdrianC
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Re: Battery voltage

Post by AdrianC »

Ralf85 wrote:I have not checked the amperage.

Yes, you need to do that to see why it's losing charge. It's definitely charging, although not massively enthusiastically.
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lloydy
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Re: Battery voltage

Post by lloydy »

wasn't there a thread the other day where Kev pointed the fault to internal part of the alternator?
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Ralf85
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Re: Battery voltage

Post by Ralf85 »

Cheers guys. I will check the amperage drain tomorrow if it's not raining and come back to you.
:ok

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AdrianC
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Re: Battery voltage

Post by AdrianC »

Ralf85 wrote:if it's not raining

Petrol van, right...? You can do it all in the dry!
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Ralf85
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Re: Battery voltage

Post by Ralf85 »

AdrianC wrote:
Ralf85 wrote:if it's not raining

Petrol van, right...? You can do it all in the dry!

Yep I know. I am in and out like a fiddler's elbow tomorrow doing xmas stuff, so if I get wet several times I may leave testing until Sunday that's all. Cheers.
:)

Ralf85
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Re: Battery voltage

Post by Ralf85 »

Ok guys. Voltage today with battery connected is 12.73V. Disconnected the earth lead and connected and checked the amperage drain. After a few minutes it settled on 0.06amp (60 milliamps?). So is that high or normal with tracker and stereo connected? Cheers.
:?:
PS I'm off to the mid-day match at Loftus Road now so catch up later.

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AdrianC
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Re: Battery voltage

Post by AdrianC »

Ralf85 wrote:After a few minutes it settled on 0.06amp (60 milliamps?). So is that high or normal with tracker and stereo connected? Cheers.
:?:

Seems high. Does it make a difference if you pull the front panel off the stereo? Can you easily temporarily disconnect the tracker?

At that draw, it'd take about 100hrs to consume 10% of a 60Ah battery's charge. That's only four days, so - yep - you'd expect problems after a week or two.
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MidLifeCrisis
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Re: Battery voltage

Post by MidLifeCrisis »

60mA could be the radio in standby plus the tracker in standby .....
This sort of parasitic current draw is why I ended up getting one of these;

Image

If I know I'm not goimg to be using the van for a while (>1week) then you just spin the green nut and it disconnects the battery.
(Downside is that you lose radio presets etc)
Additionally if you are leaving the van somewhere you can take the green nut thing with you - it hardly makes it thief-proof but it's another layer of pain before they can drive your van away...
1987 Westfalia Van, Petrol 2.0 AGG

Ralf85
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Re: Battery voltage

Post by Ralf85 »

Back home now. Cheers guys. I'm not going to disconnect the tracker. I guess I need to drive the van more and keep it charged up!
:)

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Re: Battery voltage

Post by California Dreamin »

Ralf85 wrote:Ok guys. It's starting to get dark now so I am indoors.

Main battery charged for 20 hours. Left for 4 hours now the battery shows 12.91V connected to it's van terminals. Disconnected leisure battery completely. Choke set and engine started. Voltage across the main battery terminals shows as 13.73V on choke revs. Increased the revs to 1500+ and the voltage did not change. If anything it fluctuated down to 13.70V with increased revs. Switched engine off.

Checked voltage on the leisure battery - it showed 12.66V. Connected up the leisure battery and started the engine again. Voltage across the terminals with engine running 13.69V. Increase revs again and there was no increase in voltage. I have not checked the amperage. Is that sufficient to identify the problem or do I need to do more? Cheers.
:?:

There doesn't sound like a great deal is wrong....I would however suggest that 13.7 volts 'charging' is a little low (VW spec was 13.9 - 14.2volts) infact, with sealed silver/calcium (modern batteries) this charge level needs to be even higher.. My recommendation would be to swap the regulator brush pack for a 14.5volt unit.
Like:
http://www.ebay.co.uk/itm/VW-BOSCH-1197 ... 43be0573e8" onclick="window.open(this.href);return false;

Martin
1989 California 2.1MV

Ralf85
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Re: Battery voltage

Post by Ralf85 »

I note that the charging level is a tad low. I will monitor battery levels. I have a spare regulator unit in the van so if the charge level drops any lower, I can replace the current one. This has been a useful and informative discussion. I hope that it helps others on here with similar issues. Cheers guys!
:ok

Ralf85
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Re: Battery voltage

Post by Ralf85 »

Update. I have now replaced the old regulator pack with my new spare 14V one. With the engine running it shows 13.94V up from 13.73V. The old pack was just about knackered. The carbon brushes were down to about 5mm. Is that good enough or should I be worrying about the generator?

California Dreamin
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Re: Battery voltage

Post by California Dreamin »

For a 14 volt regulator that's fine mate.....all I was saying was: the change is materials used in modern batteries, now sealed Calcium/Silver used to be Lead, has mean that the original regulated voltage of around 14 volts (typically a tad lower on our buses because of the long runs from front to rear) is a little too low to fully charge the modern chemistry of these batteries. Hence the popularity for slightly 'uprated' regulators kicking out the extra half volt (14.5 volts instead of 14)...which makes all the difference in charging these new battery types to a fully charged state.

Martin
1989 California 2.1MV

Ralf85
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Re: Battery voltage

Post by Ralf85 »

Thanks for that Martin. I do have a silver battery so I will order a new 14.5V unit and swap it over when I have a moment. Cheers.
:ok

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