Battery testing

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Fri 20 Oct 2006 09:37
Battery testing - Jimmy67
Hello to everyone.

This is my first post on this forum, petrol engines aren't my most fave. subject, rather have something with a diesel and don't have to bend my back or put on a ramp to work on - i.e. tractor, truck, excavator.

Anyway what I am looking for is information specific to standard [Exide] lead plate batteries in particular the text book correct way of initially charging prior to selling to a customer and the correct way to diagnose a battery failure.

Initial charge: From what I can gather first I need to fill the dry cells with 1.260 electrolyte [dil. H2SO4], let them stand for 15 mins, re-check the levels, then charge at a rate of 5 > 8 amperes for 4 hrs with the caps off.

Is that all or any other detail I need to bear in mind?

Customer comes to me with a flat battery wanting warranty, first I charge it up. Then take the surface charge off with a load tester, then check the voltage and gravity of each cell.....
O.K. so one cell is fizzing, so its gone down. How can I determine it is genuinely a fault with the battery and not that they've boiled it dry and thrown in more electrolyte?
What happens if all cells are down on gravity, is that just detrioration ?


thanks in advance for any pointers [or good web-links] on getting the text book procedure.

best regards
Jim





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Fri 20 Oct 2006 12:28
Battery testing - Number_Cruncher
Not Exide specific, but this looks to contain generic sensible advice to me;

www.yuasa-battery.co.uk/automotive/technical.asp

Number_Cruncher
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Sat 21 Oct 2006 06:08
Battery testing - Jimmy67
Many thanks Number Cruncher. A very useful website.

all the best
Jim
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Sat 21 Oct 2006 10:51
Battery testing - wemyss
Disconnect the live-connector second. If a CMS is used, the connector will still remain live after it has been disconnected. To prevent the connector shorting against the car, place an insulator such as a rubber glove over the connector.

"Quote from the above site" What is a CMS ?

wemyss
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Sat 21 Oct 2006 21:29
Battery testing - Number_Cruncher
Physically, it's a small battery (and all important diode) that you put in the cigarette lighter socket. It keeps a live supply accross things like the radio while the main vehicle battery is removed. Obviously this is only helpful if the cigarette lighter is normally live with the ignition off.

The reason for the diode is to make sure the small battery is not harmed or overloaded when the main vehicle battery is also connected. I don't know how true this is, but I remeber being told a story about a mechanic in the nearby Ford garage who ruined the leather interior of a new Granade by using a home made memory saver without the diode.

Number_Cruncher
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Sat 21 Oct 2006 22:35
Battery testing - jc2
F3 in the article explains it-Computer Memory Saver.
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