Re: (ET) C-185 Battery Charging

["David Roden (Akron OH USA)" <etpost drmm net>]

On 21 Aug 2013 at 20:48, Ron and Dianes E-mail wrote:

> Batteries are full of water.

I hope you mean they are full to the split ring indicator inside the cell 
caps.  They should only be that full when they're at 100% charged.

> My hand held Volt meter reads 40 volts but my gauge on the tractor says
> 3/4 full. Should I continue charging( Too what voltage) or change the
> gauge? 

I wouldn't trust the ET gauge.  But then if you have a cheap Harbor Fright 
or similar digital voltmeter, you probably shouldn't trust that, either.

Also, if you're reading the voltage with the charger turned off, don't 
even 
bother measuring that.  Open circuit voltage isn't an accurate way to 
measure state of charge.  

You want to see about 43 to 44 with the charger running and with charging 
current holding at around 4-5 amps.  (Bummer that the ETs don't have 
ammeters for charging.)  That's more or less the definition of "full" with 
a 
fairly fresh battery.  

If you've been using the lift or lights, you might want to let it run a 
while longer to equalize the pack, though.

A much more accurate and reliable method is to measure the specific 
gravity 
of the battery electrolyte with a temperature compensated hydrometer.  A 
SG 
of 1.265 or more means 100% charged. At a SG of 1.225 you're at about 80%-
90% charged.

Also realize that as your battery ages, its "full" voltage and SG will 
decline.  The voltage and SG also change with the temperature of the 
battery, which is why a temperature compensated hydrometer is a good idea 
- 
as is a temperature compensated charger, which the stock GE charger is not.

Hope this helps!

d