2010 CC Precedent Dies but comes back by removing/putting back Cart Negative

[CP241]

Please double check the voltages with a meter and let’s not rely on the SOC meter for now.

Mid 40’s SHOULD put the batteries BMS in protection mode. And if it’s dropping to the low 40’s pulling out of the garage under a light load, and assuming the cart is otherwise stock, something is wrong. And 3.3-3.4kw is a 65-75 amp load which is excessive pulling out of the garage under a light load.

To give a comparison, my 2008 DS has stock motor and controller with a speed magnet and allied lithium batteries. On flat pavement going full pedal accelerating from a stop it rarely goes above 70 amps. Going up a hill with an enclosure and kids in the back it’ll get up over 100. Cruising full speed pedal to the floor, flat pavement is rests around 40-50amps. Lightly accelerating in my driveway, pulling in/out of my garage I doubt it ever goes more than 15-20amps. This is all going off my renogy meter. Voltage off a fresh charge doesn’t drop below 50v under full load, and after about 20-30 miles it will drop to around 48v under full load. That’s when I know to go home

What kind of batteries are these? What is their amperage capacity? Do you have a spec sheet for them? Have you tried measuring the amperage draw manually with an amp clamp or something to confirm the meter accuracy?

Perhaps I’m overthinking it but if your meter is correct, unless you’re pulling out of your garage full bore pedal to the metal something isn’t right. Perhaps a motor or controller problem causing excessive draw? Or maybe your batteries aren’t really fully charged? If it’s dropping to the mid/low 40’s that’s definitely no bueno, especially for lithium.

[TNdave88]

I did know you meant pulling out of the garage, those Kw numbers were going full speed up a slight incline, that's the only time I looked. I have no idea what they are pulling out. The voltage could have been different. I just remember doing math in my head about Kw bc I had no idea the size of the motor, is the only reason I remember that. It seemed everything was working so wasn't worried. Battery voltages are tested with my Fluke meter I use at work, again just talked about the SOC as a general while driving and glancing down. No I haven't used a clamp meter while driving yet since I don't live there. They are Allied 60ah batteries and I'm not liking that company after reading too many bad things about them but when I did check voltages when I was there everything seemed in the range of normal, we went for a test ride and everything was fine. That was the last time I was there, the cutting out happened again afterwards and after using it multiple times/charging. I'm supposed to go back Sunday so I'll try and get my clamp meter on it, just never went there since it was "working"

[TNdave88]

Also I'm just curious because I'm not well versed on 12v dc, how would removing cart negative reset the bms in the battery? Seems like nothing changes voltage wise. Is it just sensing a load?

[Volt_Ampere]

Something is sensing a load or using battery voltage to maintain a state. Disconnecting allows all of the power supplies in electronics to drain down to zero and it's resetting some state somewhere. Some BMS work this way.

[CP241]

I would give allied a call. There’s been a few members here with the 4x12v setup that have had problems. It may take a little persistence but if you push them a bit, they’ve upgraded the other folks to the 48v 30aH packs to replace the problematic 12v setups.

I’ve had the 48v allieds for a little over a year now and absolutely love them. Not one complaint whatsoever. I recently picked up a 3rd battery for 90aH just to help spread the current load a bit in cold weather, but if I were in Florida still I’d probably never need more than the 60aH I originally purchased.