Dumb battery charger ?

[vpracer]

Trying to charge up some dozer battery's. I have a century 200amp wheeled charger. When I plug in and begin charging, on the 40amp setting, it dawned on me to wonder whether the 15amp circuit I'm plugged into will produce more that 15 (ish) amps. So am I getting a 40 amp charge or a 15 amp charge. Or maybe the charger itself has the ability to hit the 40 amps. The amp meter on the charger reads zero, even after a couple hrs plugged in. Batteries are completely discharged maybe?

I'm an accountant not an electrician so go easy on me please!!!

 

[BillK]

vp,
40 amps at 12 volts is only about 4 amps at 120 volts

 

[BillK]

If you want a more technical explaination ........ Power(watts) = Voltage x Amps

So 40 amps x 12 volts = 480 watts

480 watts divided by 120 volts = 4 amps

That is in a perfect world and there will be some losses etc but close enough

 

[vpracer]

Oh yeah, the old 12 v vs 120 v deal. Ah ha. I knew it was simple, that you gents.

 

[theoldwizard1]

If you want a more technical explaination ........ Power(watts) = Voltage x Amps

True for DC. Mostly true for AC (not worth discussing at the power you are talking about).

 

[Lelandwelds]

Off topic, but, does anyone know where to get a dumb charger? Other than building one? Having a battery charger that only recharges "slightly discharged" batteries doesnt help when you have knocked Richard in the dirt.

 

[Racer_X]

Off topic, but, does anyone know where to get a dumb charger? Other than building one?

Any good old fashioned Schumacher or equivalent will have a manual setting.

http://www.batterychargers.com/ps-1022ma/

 

[apollo11]

Off topic, but, does anyone know where to get a dumb charger? Other than building one? Having a battery charger that only recharges "slightly discharged" batteries doesnt help when you have knocked Richard in the dirt.

estate sales

 

[jvitez]

Off topic, but, does anyone know where to get a dumb charger?

http://usabatterychargers.com/Portable_Chargers.htm

They have everything from a basic 6 amp manual to a 20 amp manual with 60 amp starter/boost feature which is the one I have. Heavy, well built, works well for deeply discharged batteries.

They also sell automatic chargers.

 

[jvitez]

...The amp meter on the charger reads zero, even after a couple hrs plugged in. Batteries are completely discharged maybe?...

Check the voltage of each battery. If the voltage is very low the batteries are probably in need of replacement (11.5 V gives about 10% charge, meaning a sulfated battery if it's been like that for a while).

Can you open the cells and check the specific gravity with a battery hygrometer or are the batteries fully sealed? Are they old?

You may want to leave the charger on overnight. A very discharged battery will accept minimal amperage until it starts to become partially charged, so it may read higher after 8-12 hrs.

 

[Ole Slewfoot]

Or hook some jumpers to your truck before turning on the 'smart' battery charger...

 

[Oldbear]

Or hook some jumpers to your truck before turning on the 'smart' battery charger...

I've used an extra battery hooked to the dead one with booster cables just to get my smart charger going - then disconnect the good battery after 10 minutes or so. Often enough to get things rolling.

 

[theoldwizard1]

Off topic, but, does anyone know where to get a dumb charger? Other than building one?

Buy a good 12VDC power supply like one of these. You will need a decent DMM to set the voltage.

A lead acid battery will not start charging until about 13.2V 14.0-14.5V is not unreasonable, assuming that the plates are fully covered in acid AND you have a timer on the power supply !

 

[Bert_]

Off topic, but, does anyone know where to get a dumb charger? Other than building one? Having a battery charger that only recharges "slightly discharged" batteries doesnt help when you have knocked Richard in the dirt.

I've never had trouble finding one

The main charger I use came from bomgaars, bought just a couple years ago. It's a schumacher 10/30/200 amp unit. Also have a 6/10 amp unit that I found a bunch of years ago.

 

[joe_padavano]

Off topic, but, does anyone know where to get a dumb charger?

Amen. Why are "smart" chargers not so smart? Thankfully, I still have my ancient "dumb" battery charger that's been working great since the 1970s. The "smart" charger I have usually claims that there's a fault if the battery is really discharged. No such problem with the old charger, and the allegedly "faulted" battery works just fine after charging.

 

[Dragfluid]

Dad got one in the early 60's. About 12"x12"x12". Weighed at least 20#. 6&12V on one switch, charge and boost on the other. We still had a couple tractors that had a single 6V, so it worked out well. Man, that thing would really get something cranking after a short while.

A couple years later, the folks got into a new grocery store, located in a 200 unit trailer park, about a mile from home. Dad made the mistake of borrowing the charger to one of the customers. Well, from that guy it went to someone else, and so on and,,,,,,,,,,,,,,. When dad finally located it, he got smart and took it home and then told people that it didn't work anymore.

I still used it for many years after, until it got to the point of it wanting to charge ME whenever it was plugged in.
So I finally had to say goodbye.