Dead batteries, won't charge

[movin-on]

Can't you just bypass the relay on the charger to get it to turn on...
http://www.buggiesgonewild.com/elect...s-charger.html

yes ... if you have the old powerdrive charger

[Sergio]

FYI, this is the jumper procedure for the PowerDrive 3:



With the batteries that low jumping the charger will likely damage the OBC or the charger.

Your best bet is the 12v charger.

Disconnect the pack negative cable so the OBC resets while You perform the individual battery charging.

Charge 2 batteries at the time first since the individual voltages are too low, then each battery individually.

You will most likely need new batteries.

As mentioned before, You either left the lights/accessories ON or You have a wiring problem.

The batteries cannot self-discharge that low in that short period of time.

[PingEye3]

I have to tell this story. I had a friend who bought a cart which had 1.5 year old batteries but had not been charged or driven in a year. Total pack voltage was 18V about 3V per battery. Of course the charger would not start. I used a set of jumper cables and jumped from a good 48V pack cart to this pack and plugged in the charger. I left the cables connected for about 5 minutes. When I lifted the jumper cables from the fully charged cart), the charger continued on. The next day after an all night charge, the cart was driven 2 miles to the course, I followed with a tow rope expecting it to die on the way there. But, it did fine and the new owner played 27 holes that same day with no problems. The batteries came back up to the 50.9V fully charged level. They lasted about 2 more years. I am still amazed at that one.

Any thoughts on jumping from 48v pack to 48v pack with jumper cables? Very convenient and it worked beautifully. Done it this way several more times.

[Sergio]

I think as a general rule, it is a very high risk procedure.

The main reason is if you have a shorted cell, a regular charger will stop at less than 20 amps if by-passed and much less if properly monitoring the output.

A jumper from another pack can discharge upwards of 500 amps in an uncontrolled manner.

if You checked the batteries personally, know the age of the batteries and conditions that caused the discharge, You can take a chance on that procedure, but without a doubt it carries a bigger risk than using a charger.

You should also reset the OBC anytime the batteries are charged without using it.

[PingEye3]

I can assure you that I was cautious and knew the history of the batts as well. Self discarged after sitting for a year or so. The initial connection of the packs was my biggest concern. However, being a retired electrician and also ex navy elect. working on small boats and batteries on a submarine tender gave me the confidence to do it that way.
Thanks for your insight.

[_ogre]

Originally Posted by jondrew

Finally, I put a volt meter across the batteries (4 - 12 V Trojan batteries, still wired to the cart). They all read between 1.5 and 2 volts.

for the record: the relay inside the charger is 48 volt and controlled by the obc
not enough voltage to pull in the relay, thus the relay bypass or charging each battery works

Originally Posted by _ogre

for the record: the relay inside the charger is 48 volt and controlled by the obc
not enough voltage to pull in the relay, thus the relay bypass or charging each battery works

get new batteries

[jondrew]

Originally Posted by crash test dummy

get new batteries

Got new batteries

Next question is, for the way I use this cart, what's my best strategy for keeping these in good shape? As I said before, this is our "Disney" cart. We got it because it was such a hassle reserving carts at Disney Ft Wilderness, and off property carts were a pain because Disney wont let the companies drop off on property.

So we really only use it a couple of times a year. The rest of the time it sits in the garage. Someone in a previous response asked why I didnt leave the cart plugged in all the time. I guess I was just afraid of a possible explosion/fire in my garage. Maybe that's not a real problem, I don't know.

The other thing I was thinking was when I am not going to use it for an extended period, just give it a good charge and disconnect the cables. Then maybe charge/drive it once a month.

Opinions welcome (I'm sure there are plenty)

[NoleFan4Ever]

The OEM charger will kick on automatically in 14 day increments.

Some aftermarket chargers that are used in place of your OEM have float modes (trickle charge) but the OBC is removed or bypassed.

You can easily purchase a trickle charger/battery maintainer that will sustain your batteries while not in use so it is ready when you are. What you do not want to do is just let it sit with nothing for long periods of time as that will ruin the batteries over time. Even if you disconnect the pack, the batteries will still self discharge over time. Now there are a lot of variables that play into all these scenarios, ie: duration, pack condition, usage, frequency, etc. etc.

If it were mine and I was using it as you are, I would let it charge as normal on my powerdrive charger and then hook up a battery maintainer to keep everything topped-off while sitting in waiting.....