The Museum of HP Calculators

HP Forum Archive 13

 How long should I charge the batteriesMessage #1 Posted by Arnaud Amiel on 5 Nov 2003, 1:33 p.m. I have rebuilt my 45 battery pack and used 650mAh NiCad. I believe the original was 450mAh and had to be charged for 14h. Am I right in thinking I should charge mine for 20h. Thanks for your input Arnaud

 Re: How long should I charge the batteriesMessage #2 Posted by Bill (Smithville, NJ) on 5 Nov 2003, 1:49 p.m.,in response to message #1 by Arnaud Amiel I've always used the following for NiCds: (1.5) times (battery capacity) divided by (charger capacity) = hours Assuming the HP-45 charger is 50 ma, then 1.5 x 450 / 50 = 13.5 hours 1.5 x 650 / 50 = 19.5 hours So, 20 hours should be about right.

 Re: How long should I charge the batteriesMessage #3 Posted by David Smith on 5 Nov 2003, 3:42 p.m.,in response to message #1 by Arnaud Amiel Most of the original HP packs were 600 maH. Some very early ones were 500.

 Re: How long should I charge the batteriesMessage #4 Posted by JasonG on 8 Nov 2003, 2:55 p.m.,in response to message #1 by Arnaud Amiel Aha! Charge them all the way to the end, right from one end to the other. Anything else leads to a big bulge at one end and then it won't fit into the battery compartment. Wooooooooha! JasonG... PS: Sorry for the frivolity...it's just a wild reaction against a very crap week...

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