Battery drain

[reinman88]

A month or so ago you guys helped me out when I was trying to figure out if I had a battery problem or a charger problem. I have an 08 drive with 4 12 volt batteries that are one year old.

In the end we felt the batteries were fine, so I hooked my voltmeter to the pack and leave it there so I can keep track of voltage.

Everything had been going fine and voltage was usually about 51.5 after a charge. Voltage under load was usually around 46.6 on a flat gravel drive, and after a few miles that voltage may be 45.8 give or take. I'd usually charge batteries at 49.5 volts when rested.

It's been raining all week so I haven't gone anywhere with the cart of any distance. Back and forth to my kids house a few times and down the drive to pick up my granddaughter after school. I last charged the cart on Saturday night, and it was at 51.5 volts on Sunday after the charge. I have probably used it a 1/2 mile or maybe 1 mile at most. It is now Thursday and when I went down to get the mail I flipped on the voltmeter, and going down the drive I was at 42.5 volts. I let it sit about an hour after getting to the house, and the pack voltage was 48.5.

I have nothing hooked to the batteries. All lights and other stuff come off a 5th battery. When parked overnight I do not always shut off the switch, kind of got used to that with my gas cart. Is leaving the key on draining my batteries? Dropping to 48.5 volts in 4 days with little use seemed like a big drain to me.

[rib33024]

How long after a full charge does it take the battery pack to get down to 51 volts at rest?. after a full charge, you need to hook your meter to each battery and see if any one or two batteries drop lower than the others, you could have one bad battery or two

[Volt_Ampere]

With the pack at 48.5, I would measure all of the batteries one at a time. You may have a failing battery that is self discharging much faster than the others.

[reinman88]

I tend to doubt a bad battery. The reason I say this is last month when I thought I had a bad battery I was doing extensive tests on all batteries. Checking voltage on each battery under load, then later checking pack voltage at rest and each battery at rest. I'd do this again after maybe 3 miles of driving, and then do it all over again after about 5 miles. Each time testing pack voltage under load and at rest, then doing the same to each battery. In all cases all the batteries where about the same.

Now that being said, could one battery drain down over 4 days while the other 3 didn't is possible. My other tests were after one day of driving so there was no long period of time between charges. Right now I have the cart back on the charger. Tomorrow I expect to see 51.5 volts. My plan is to let it go 4 days without charging and this time watch each battery daily over those 4 days. I will use the cart about the way I did the last four days. This should tell me if one battery drains down over a period of time as you have suggested.

My concern was leaving the key on and that draining my batteries.

I'd also like to say 2 answers very quickly, and I didn't even have to write HEY REDNECKS in the title line.

[cgtech]

Leaving key on is likely a drain.

[reinman88]

Thanks, I'll try to make sure I shut it off each time from now on.

[Soul Searcher]

Greetings reinman88,

Just asking for my own Knowledge Bank. Are the Batteries, Sealed Lead Acid , or with caps, to add Water? After you charge the Batteries, are they warm to the Touch? Are you using a Digital Volt Meter, to check the Voltage? Thanks,

[reinman88]

The batteries are 12 volt Trojan and yes you add water. Can't say I've ever touched them to see if they are warm after charging.

I'm using a digital voltmeter, but not a built in one. Actually the voltmeter I had was bad so I bought a new one. The leads from the old one fit and worked on the new one, so I cut the ends off and added some wire. I ran the wire under the floorboard and came up in the dash where are there some golf ball holders. I put the voltmeter in there for now.

This way I could continue to test the voltage for the full pack, and I could still go under the seat, swap the leads around, and check each battery individually. I'm letting it go this way for a while so I can keep an eye on the batteries.