battery and charger questions/ issues

[JohnnieB]

Hopefully, you flipped Run/Tow switch to Tow before disconnecting battery.

Whenever the batteries are connected, there is a small amount of current flow due to the 250 Ohm resistor across the solenoid contacts. There are a bunch of filter capacitors in the controller and the charge on them bleeds off, the current flow through the resistor keeps them charged so the solenoid contacts don't arc as much when they close.

When the Run/Tow switch is in the Run position, some parts of the controller are active and additional current flows.

The combination of the two is still very low current, only a few Milli-amps, but enough to load the batteries ever so slightly. That is most likely why the voltages climbed slightly when the battery loop was disconnected.

A weak battery doesn't actually bring down the voltage of batteries connected in series with it, but the same current flows through all batteries connected in series, so it limits the rate current can be drawn from the pack and screws up how much the stronger batteries are charged.

It is a bit of a vicious circle. The charger assumes all 6V batteries are equal and shuts off when the average on-charge voltage is approximately 7.5V per battery, or about 45V for a 36V battery pack.
The net result is the battery with lower on-charge voltage is charged less and the others are charged more.

The trick is to get the batteries closely matched. Fortunately, lead acid wet cell deep cycle batteries aren't too picky about who they hang out with and slight differences can be smoothed out over time.

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Have you check the fluid levels in the batteries?

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Replacing the weak battery with a good used one might help, but I'm not sure if it will solve the problem.

I wish your cart was sitting in front of me right now. I'd put a known good charger on it and put the QE on a known good set of batteries.

[3ftover]

Ok quickie needed please. Found a reconditioned battery locally for $50. Not a match to what I have now trojan t-105 225A. She said this one is rated for 220A. Can't tell me brand. Should I? Batteries I have now are two years old so she said they put out 225A new but prob not anymore so it should be ok. Hopefully I get a response from some helpful person as I intend to head there at lunch today.

[3ftover]

Alright now I'm stumped!!!!! Bought reconditioned battery. Btw when I got to the battery place the bad battery voltage was 4.9. It was 5.8 this morning. Replaced battery. All readings on each battery well over 8v. Total pack over 48. Keep in mind this is a 36v pack. ??? Anyway, rode the cart thinking I could ride forever. Not so fast my friend. Rode about 3 miles, maybe 4. Cart power very low but battery.....voltage well above 7v. Total pack, 46v even. PLEASE HELP! I rode longer with the bad battery!!

[3ftover]

JohnnieB to answer you earlier question yes all fluid levels good

[pggroves]

Check your meter. A low battery in the meter can give false high readings.

[3ftover]

Are you kidding me. Agghhh! Well I learned something new. Thanks PG, that was it!!

[JohnnieB]

I got called away to batten down the hatches in anticipation of a visit by Sandy.
I'm getting wind & rain with some freezing rain & snow tossed in, but the blizzard conditions are mostly to the east of me.

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Ouch!!! - A bad battery in the DVM. I hadn't considered that possibility.

That means all the previous voltage reading are suspect, and you say you were getting more run-time with the "bad" battery in the cart.

Did the QE charger go all the way to a solid green LED when you charged the pack?

What are the battery voltages now that the DVM has got a fresh battery in it?

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Voltage aside, you mentioned your cart had low power after 3 or 4 miles.
That sounds like the batteries either aren't being charged or not holding a charge.
You ought to be getting more run-time/distance than that.

For example:
In Mild Hill PDS mode with 18.4" tall tires, ~500 pounds of driver and passenger, a set of T-105 batteries with a "L9" date code that were not well maintained before I got them, I routinely make a 10.2 mile (GPS) trip over a mix of paved & gravel roads and cross country with 100' long 30° upward incline and two 10° half mile upward inclines and my pack voltage is 37.6V (~80% SoC) when I get home.

IIRC, you've got taller tires, which take more amps to turn, but you should be getting something in that general vicinity.

[3ftover]

I'm live in S Louisiana so Hurricanes are a norm. Good luck to you.

LED was still blinking green this morning. I want know until I get home today the outcome.
I did check the voltage and all were at about 6.8 except the reconditioned one. It was at 7.1.

No I think all my readings were good up until the point I installed the reconditioned one. Just coincidence I guess. Readings after I changed the battery were consistent with before. It was dumbfounded for a few minutes though.

I do have 22" tires. My cart goes pretty fast. I need to clock the speed though and determine of any kind of a chip is in there though. I'll try a GPS this evening. This evening hopefully will be the first real test with hopefully a full charge.

[3ftover]

Well I had my wife check the charger. No dice. Blinking red. Three blinks which I have read means the charger timed out but it has not been 24 hours. Only 12 or 13. LED shows one bar shy of fully charged. I'll check the voltage when I get home but for the time being I had her unplug and replug. Blinking green again. Very frustrated. Cables seem to be fine but maybe that is my next step to replace.

[JohnnieB]

I had the "pleasure" of welcoming a Cat-5 hurricane named Camille onshore back in August 1969.
Fortunately, I'm about 300 miles inland for Sandy.

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Be sure to clean the connections in the charger plug and receptacle also. As well as the Black and white wires to the battery pack from the charger receptacle. If there is a 60A fuse in the white wire, be sure to clean that connection too.

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If at all possible, try a different charger.

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You can find out what chip you have by putting it into the diagnostic mode.
The text at the bottom of attached label tells you how and here is are charts with beep codes and the performance for the four PDS modes.

With 22" tires, your top speed will be ~22.5MPH. (With good batteries and high current cables. )