1986 CC 36v conversion to 48v

[killsumptin]

That's SSSSwwwwweeeeetttt! I love a good deal!

My batt.s alone are going to run $200.

I did get a deal on some heavy cable on ebay. The cable was a bit larger than I wanted but I'll make do.

[scottyb]

$200 is new battery prices. If your existing battery pack is more than 1 to 1 1/2 year old it may not be a good idea to introduce new batteries.

[napalaz]

check out gornomans post on how to wire the charger so you dont have to disconect the wires to your additional bats to charge supper easy

[Nate]

1986 CC is a good year, they have the Yamaha diffs. 1982, 1983 and some 1984's you want to avoid (Fuji diff). 1975 to 1981 with the Terrell diffs are excellent built carts. Ride a bit rough and need 16 spline motors but built to take some power and they have 8:1 gears!

“Nate shunt” is not correct; I don't recommend shunting a series motor. Amps go unchecked and things burn up.

Some chargers can be connected in series without issues. I have in the past used six 12V chargers to charge each 12V battery individually without disconnecting them from each other. The key is to use chargers with isolated outputs. How do you tell? That is not quite as easy a question to answer. I can tell you this, if they are not isolated you will know immediately when something burns up in a big way!

[napalaz]

Nate I don't understand I thought current output was Isolated by the negative flow if you connect a meter to 36v pack on the first and last it will read 36v if you connect to first and second it will read 12v and if you connect a 12v charger to the first bat and second the circuit is closed at 12v and not 36v

[Nate]

Naples said "if you connect a meter to 36v pack on the first and last it will read 36v"
This is correct

"if you connect to first and second it will read 12v"
For 6V batteries this is also correct.

"if you connect a 12v charger to the first bat and second the circuit is closed at 12v and not 36v"
Correct again. You do have a good understanding so I am not sure what it is you missed. Looks like I missed something.

[scottyb]

Does someone have a link to Gorno's charger diagram handy? I'd like to see it.
Makes sense to me that you could hook a 36v charger to first six as normal and also hook up a 12v charger to the remaining two batteries since each charging system would only work between it own pos and neg connections....

[napalaz]

Thanks Nate I just wanted to make sure I understood what u were explaining

[Nate]

Transformers by nature are isolated devices but on occasion the manufacturer will make the DC negative the same potential as the AC ground.

If you got hold of this type of chargers (both would have to be non-isolated) there would be a conflict at the battery pack

Example:

36V charger hooked to first six batteries like normal. The negative post on the pack is at the same potential as AC ground. No issues.

Hook a 12V charger that also shares the negative pole with AC ground and hook it to the last two 6V batteries. Let's say the extra two batteries are on the positive side of the 36V pack. Batteries 1-6 are the 36V pack and batteries 7 & 8 are the 12V boost. As soon as you hook the negative 12V lead to the negative side of battery 7 there would be a conflict since it is connected to the positive post of battery 6. The 12V charger and the 36V charger have their negatives at the same potential, AC ground. Your 36V pack positive side would have a current path through the 12V negative lead to the AC ground then back into the 36V charger negative lead and back to 36V negative pack.

I have yet to find a non-isolated transformer in the golf cart or automotive world but they can exist.

[scottyb]

I sounds risky to share common grounds with ac and dc. If a short occured in the ac unit , it could potentially fry your dc. NO?