JohnsonMfg said:
Thanks for that link. I had already found & read it, but being a non-technical person, don't really understand it. I was looking for more layman's instructions on the settings for my type of batteries.
Hi JohnsonMfg,
I think you need _9_, not 6 batteries to multiply by 8V to give 72V. It has been done, I found some threads in the old yahoo GEM group:
http://autos.groups.yahoo.com/group/NEVs/ but I couldn't find what they did with the charger. Try to get in touch with Ricky there, might be your best bet.
Maybe you're lucky and have this funky rotary switch, look at this site: http://gemcar.blogspot.com/2008/10/2002-e825-charger-update.html
But that is only basic Gel/Flood, it won't be the exact right charge curve for your usb, and it will probably time out before the bigger capacity 8V's are full. You might be able to workaround that by using a simple plug in timer (like a Christmas light timer) to re-start the charger.
USB floodies have different charging recommendations than the Trojans. Best to look up on the usb site with the model you want to buy... or maybe better to get Trojans instead, as you're more likely to find the right chip. Trojan T875 are the cheaper, most common ones, and what people have converted GEM's to.
To select a different algorithm in the charger, you need to first find out if your chip version has the right algorithm, and which jumpers to put on to select it. There might not be a selection for usb and might not be a selection for 8V's (higher capacity.)
You might be best off with advice from a GEM dealer. You could try to get something out of Greg McCrea or his employees at www.zivanusa.com But good luck. Greg has awful service. Once I bought a brand new $1800 NG3 from one of his dealers, and emailed to ask for a pinout of the temp probe. He replies back with just "Who are you?" Huh! my email told him exactly who I was, and that i had just bought one of his chargers. Why doesn't he just have this stuff on his website?! And he names his chips with cryptic codes instead of just printing synopsis of the algo's on them. Even when dealing with him from a company, he never gets back to you, then sometimes you just get lucky and he tells you on the phone. Instead of just implementing the manufacturer's recommendations, he always comes up with some aglo that is different for his own reasons. Every time we ordered a batch of chips, Greg gave us a yet another different version, with some unclear story. Greg is the worst thing about Zivans. Too bad Zivan went with him as their American rep.
Anyway, to find out what algorithms are available to you without buying a new chip, you need to open your case and look at the code on the chip. You just poke the center of the 3 little black pops on the aluminum side, then push out the X part. Then pull up the case on the side opposite the grey output connector first. Then push the case towards the output end to slide it out free of this connector. The chip is on the daughter board, and in our case the codes were always written in black sharpie, like "Y1.9" or something. Obviously this tells you nothing, so then call a GEM dealer with the code, cross your fingers, or try to google it.
Good Luck,
John
