Battery charging/ meter problem.

[weaselorlando]

My son in-law sent me this information on our G19 cart. I am on a trip and will try some trouble shooting tomorrow. I have a replacement digital volt meter on order. Does this sound like it is related to the meter or something else? Looking for some trouble shooting tips. Thanks

We took the golf cart out for a drive and it ended with roughly 1/4 charge left. Plugged cart into charger as normal and it showed no faults.

Later that night I went back to check to make sure the cart was still charging as it has stopped on a few occasions and I have had to restart the cycle. This time the cycle seemed to be running normally.

I checked on the golf cart in the morning and the charger showed full charge. I checked the charge meter and it showed no change, this has happened before. The "fix" for that is to remove the charge meter and reattach the wires and it updates. This time it did not update, so I plugged the cart back into the charger and it started the cycle over in the beginning. I had this same thing happen earlier in the week.

After 45 minutes the charger showed 60% charged and the cart charge meter showed full.

[kev2504]

you should check the battery pack voltage and see what it is. you can also check each battery separately to see what each one is at.

[weaselorlando]

That was definitely my first step. I will post results here tomorrow.

[Unsoshl]

Certainly check pack voltage after 12 hours off charger. 50.9 is full charge. Also, I hope you got a digital volt meter that has the actual voltage, like the one ScottyB sells (check site sponsors). Those other meters with the bars are completely useless, and I too have had them display 1/4 charge when cart is fully charged.

[weaselorlando]

I checked the batteries this morning.
Pack voltage 50.1
8.27
8.55
8.46
8.29
8.32
8.31

Pack voltage under a load: lowest momentarily value was 34.9. Stabilizing at 43.3.

Batteries 2 & 3 are 2016. The other 4 are 2009. So I would assume that I need to replace the 4 older batteries.

I have a new digital volt meter on order.
I still wonder why we were getting the strange behavior of the battery meter?

Why the need to disconnect the meter in order to get it to refresh and display the battery level?

Would you think the replace digital volt meter will solve this?

Will the digital volt meter install with the same wire configuration as the the battery meter we have now?

[kernal]

So the pack voltage at rest is 50.1. That is less than 85% charged. This indicates the capacity of the batteries as a pack is way down. Most likely because of the age of 4 of the batteries. They are at end of life. Also a 48v pack should not dip below ~ 42v under load. Another indication the batteries are gone. Probably why you are only getting 17mph out of that cart also.

You should never mix batteries of different ages. Batteries in series should be all the same age and capacity. A matched pack if you will. Here's why. As batteries age their capacity goes down. The 2009 batteries have way less capacity then the 2 2016 ones. The older batteries will charge faster then the newer ones. The charger doesn't know this. It is looking for total pack voltage to rise to a certain pre set peak then it shuts off. The older batteries are being chronically over charged and the newer batteries are being chronically under charged. You are killing the 2016 batteries. The newer batteries are quickly deteriorating (aging) to equal the older ones. It is best to replace all the batteries at once. Over the years I have found the best prices at John's golf cars or Big O's. Suggest you call around tho.

Regarding the meter. I don't know what meter you have but a very common one in PTC is the curtis model 906. It is the factory unit on many EZGO's, Club Cars and Yammies. It can be horizontal or vertical. It is a LED bar graph with a red segment that moves from right to left (or top to bottom) as the battery charge depletes. Works like a fuel gage. As the batteries charge the meter is looking for 2.35v per cell or 56.4v for 6 minutes on a 48v pack. Because of the poor state of you battery pack the charger is likely unable to bring the pack voltage that high so the meter never resets. If you disconnect one of it's leads the meter looses its' memory and assumes it's been connected to a fully charged pack. It doesn't have a good reputation on this forum but it is very common in PTC and has given me good service on several carts over 17 years. Odds are the meter in your cart is fine and will work normally with a new battery pack.

The digital meters are technically more accurate because they are displaying actual volts. The problem with them is they are near instantaneous and cycle while your driving. You also have to stop and let the battery pack stabilize for about 15 minutes to get an accurate reading of actual state of charge and then you have to memorize the chart or tape a copy to the dash or something. The women and house guests that use my cart object to it with enthusiasm.

Hope this helps.

[weaselorlando]

Thanks for the background info on batteries. Make perfect sense to change out all 6.

[cgtech]

Kernal, that was a very nice description of the meter, the batteries, and the merits of the "easy one" vs the accurate one. Try explaining the "volt meter" to someone who knows not a thing about a battey (good luck). If I were not facing that battle, every cart I sold would have a volt meter. But, they care not of the details of a lead acid battery, it just must take them everywhere they want to go, who cares about one crappy battery fudging up the mix.

[weaselorlando]

Can I have the best of both worlds? Anything preventing me from keeping the old meter and adding the digital one? Can I tap into the same wires going to the current meter?

[kernal]

Yup