Significance of AH and volts when recharging.

[golfcarts]

I'm trying to figure out the cost of recharging. I deplete my golf cart batteries approximately 30% everyday and charge it every night.

What is the typical AH rating for 36V batteries?
How much energy is my Wall Charger drawing, and costing me?

I want to know what is a good equation to figure out how much the wall charger is drawing out in relation to the AH it takes to recharge a 30% depleted battery.

[scottyb]

....... where is an electrical engineer when you actually need one?

[dougmcp]

Originally Posted by golfcarts

I'm trying to figure out the cost of recharging. I deplete my golf cart batteries approximately 30% everyday and charge it every night.

What is the typical AH rating for 36V batteries?
How much energy is my Wall Charger drawing, and costing me?

I want to know what is a good equation to figure out how much the wall charger is drawing out in relation to the AH it takes to recharge a 30% depleted battery.

Your question is nearly impossible to answer in a simple format or equation.
Here are some factors:
GC-2 batteries are typically rated around 220AH, but not all (Trojans are 225AH for the T-105's)
Your amp hours are only as good as the weakest battery.
Your charger typically draws between 14 amps and 2 amps at 120VAC depending on where it is in the charge cycle.
Your battery condition determines how long the battery charger is at different stages.
A 3 stage charger has a different amp draw than a ferro resonant charger.
The KW cost changes during the season and sometimes between peak and non peak hours.

The only true way to find this out is to put an recording energy meter (Watt/Hour Meter) in line with your charger and multiply it's reading with the cost of a KW in your area.

[eflyguy]

I have such a meter, but have my electrics removed while I work on the speed control mount plate - once I get it back together I will put it on charge and see what it draws. 20A @ 38V is 760W, which is only 7A or so from the AC source (of course there are losses) - if you wanted to fudge it, round up to 1kW, and see how many hours it charges for. Ours doesn't seem to need more than an hour or two, so that's about 2kWh, or $0.20.. :)
..a

[eflyguy]

Got my bracket tapped and re-installed, so we ran it up and down the driveway (1/4 mile, 400' elevation change) and then put it on charge. Jumped to 20A on the charger, and my meter reads 8.5A / around 1000W - so "fudging it" turned out to be right on.

This is for 36V, of course..
..a

[golfcarts]

[QUOTE=dougmcp;231365]
Your charger typically draws between 14 amps and 2 amps at 120VAC depending on where it is in the charge cycle.
Your battery condition determines how long the battery charger is at different stages.

[golfcarts]

Thanks for the response. If I was only charging my batteries for the final 30% till top off. How much amps would the 120V charger be drawing? 2? 5? and how much time do you think it takes to top them off?

the batteries all read above 6V, the system reads 38V, so they are all well maintained batteries. 36V golf cart system.

[eflyguy]

Did you read my post?
..a

[oxfordlawn]

this may help answer your question--read this thread

http://www.buggiesgonewild.com/elect...ht=cost+charge