Carryall 2 Allied Lithium Drop-in OBC Bypass Problems?

[Rebelhoo]

Bump for any new thoughts…

[Pat911]

If you’re getting 14v per battery and pretty much 0v on any two or more series connected batteries then the connection between the batteries is faulty. Can you post a picture of how you’ve connected the batteries together please.

[Rebelhoo]

Here’s a pic from the front and back.

[Pat911]

Make sure all terminals are clean and ensure you’re measuring the voltage correctly. You should be getting 14v, 28v, 42v, 56v as you check the voltage on each positive terminal, keeping the meter negative on the main negative.

Also, and this is VERY important for lithium, DO NOT, UNDER ANY CIRCUMSTANCE TAP OFF 12V FOR ACCESSORIES. it seems that you have multiple connections to some terminals, implying you may be tapping 12v for accessories.

You’re going to have balancing issues as it is, tapping 12v off will make things much worse. You must use a 48v to 12v reducer for accessories.

Cheers
Pat.

[DaveMJ]

Originally Posted by Pat911

Also, and this is VERY important for lithium, DO NOT, UNDER ANY CIRCUMSTANCE TAP OFF 12V FOR ACCESSORIES. it seems that you have multiple connections to some terminals, implying you may be tapping 12v for accessories.

Agree with Pat.

What voltage do you get when you measure across all batteries with the charger plugged in?

Monitor it for a minute or so an see if there's any fluctuation.

Keep meter in place and unplug the charger, what voltage does your meter now show.

[Rebelhoo]

Thanks. I am going to disconnect all auxiliary for now. I’ll let you know the test data when I can get back out there. I appreciate it.

[Rebelhoo]

With the charger unplugged, it measures .77 across the pack. That is messed up, so I tested the individual batteries with the charger unplugged, and I'm kinda baffled at the readings. The first battery (positive side of cart) shows 14.2, the second -13.8, the third 13.4, and the fourth -13.3. They seem to all be cancelling each other out. I think I have them all wired in correctly. Positive terminal to red of battery 1, negative of battery one to positive of battery 2, negative of battery 2 to positive of battery 3, negative of battery 3 to positive of battery 4, and negative of battery 4 going out to the back of the cart. Something is clearly messed up. What's making them alternate positive and negative? I guess I may unhoook them completely and see what the individual batteries show...

[Rebelhoo]

More interesting things to note... When i disconnect the red from the back side going in to the first battery in the series (or last, depending on your viewpoint), the whole pack measures correctly and the individual batteries start to behave normally. With the red disconnected, they measured battery 1: 14.15, battery 2: 10.6, battery 3: 13.4, and battery 4: 10.65. No more negatives... What's going on?!?