Battery charging questions

[DougT]

I was trying to charge a large "commercial use" 12v battery with an old Honda 1000 generator and an old Sears 10amp battery charger. I've heard that some battery chargers don't work well with generators.

Questions:

The battery measured 12.21 volts the charger was putting out 10.58v Doesn't the charger have to put out more than 12v to charge a 12v battery?

When I hooked the 10.58vcharger output to the battery, the battery read 12.58v. Is this Possible?

I'm sure this battery needs to be equalized. Does anyone know of a modlel and brand of charger that can perform the equalize function and run efficiently from this small generator?

Thank you for your help

[ghurd]

The charger is probably an older and cheaper design.  The meter was reading kind of an average DC from the pulses.  This kind of charger works fine with generators.

Many of the older and cheaper battery chargers will, basically, perform a crude equalization, because they don't actually regulate the finish charge voltage.  It can take a long while, and it will need babysitting.

Might try to find an old and simple 20A charger to speed it up a bit.

G-

[Experimental]

Hello Doug,

   Look closely at your generator, most Hondas have a 12 volt battery charging function, built in !!

Yours might not, but most do.....Bill H.......

[DougT]

Actually, this generator does have a 12v charging system, but it doesn't put out any voltage at all. I tried looking for a blown fuse or something but haven't been able to find the problem. any insights?

[snowcrow]

 Hi Doug, your generator may have an auto reset built in, and it maybe just burned out. If it is a newer 12 volt system generator, with reversed pole protection it will read 0 volts, if read open! These chargers will only apply voltage to the leads when a battery is present.

 I own a coleman 1800 watt and the 12 volt system is really only good for bring your car battery up enough to start. The open voltage on my generator's 12 volt system is 13.6 volts and will not fully charge even a car battery.

 You need 16.5 to 18 volts minimum open voltage for charging. (unless you are using the reversed pole protection kind, in which case you can't read open voltage). If the 10+ volts is open voltage on the sears charger, you need to buy a new one!

Blessings, Snow Crow

[ghurd]

I am curious why you believe he needs a new one when the old one works like it was designed to work?

The "You 16.5 to 18V minimum open voltage for charging" part has me wondering too, but it does show how a cheap and simple battery 'ruiner' can perform a crude equalization, right before it kills the battery.

G-

[AbyssUnderground]

13.6v will charge the battery eventually. It will just take a very long time. Ideally you need 14.5v to charge the battery fully and properly which when fully charged should then drop to 13.6-13.8v.