First ride in my cart

[70oldsracer]

Well, I finally finished up all the wiring on my 1995 medalist and took it for a ride today. I filled the tires to the proper specs, 20 psi and the battery pack was showing 52 volts on Scotty's digital volt meter. I drove down my driveway and went about 400 feet and the cart wouldn't go over 6 mph and the voltage was already below 48 volts. I'm using four 12 volt 75ah batteries. The cart has no power at all. I'm guessing either the batteries are shot or are just not right for this set up. I was hoping to get some run time out of them, but I'm lucky if I drove for 2 minutes. Right now (about an hour later) the pack voltage is 51.5 volts and each battery is showing just over 12.8 volts. Do you think by discharging the batteries and charging them a few time, it might bring some life back into them? Do you think it could be something else? Any help would be greatly appreciated.
Just took it for another ride and tried it in reverse and it's way more powerful in reverse. Can I have something hooked up wrong?

[70oldsracer]

Okay, I didn't know that the FWD/REV switch is actually opposite of the way I thought. When the switch is in FWD, it feeds the bottom terminal and visa versa. I had it wired up backwards, so the controller was thinking the cart was in reverse and only sending 1/2 speed. I switched the wires and all is good. Feels like it has really good torque and I'm getting a top speed of about 16 mph. I was hoping to see more like 18-19mph, could the cold weather be effecting the mph or is this right around where it should be?

[dundeebarnbuggy]

How cold?

[70oldsracer]

Originally Posted by dundeebarnbuggy

How cold?

40 degrees, with wind chills in the 30's right now.

[dundeebarnbuggy]

Batts don't care about windchills. At 40f you will notice a decrease in performance, don't know about 4 mph though. How many amps are you drawing at speed?

[70oldsracer]

Originally Posted by dundeebarnbuggy

Batts don't care about windchills. At 40f you will notice a decrease in performance, don't know about 4 mph though. How many amps are you drawing at speed?

I'm going to try to hook up the lap top today and go for another ride to get some readings. Then i'll be able to tell you the amp draw. What would you say is an expected top speed for my set up. It has a stock 36 volt GE motor and everything else is in my sig line. I'm guessing it should be between 14-18, which is exactly where I am, but I would like to be around 20 if possible and still have the same torque. I know that it's usually either speed or torque, not both, but I was hoping with a top speed of only 20, I could still manage to keep the torque.

[BobBoyce]

Originally Posted by 70oldsracer

I'm going to try to hook up the lap top today and go for another ride to get some readings. Then i'll be able to tell you the amp draw. What would you say is an expected top speed for my set up. It has a stock 36 volt GE motor and everything else is in my sig line. I'm guessing it should be between 14-18, which is exactly where I am, but I would like to be around 20 if possible and still have the same torque. I know that it's usually either speed or torque, not both, but I was hoping with a top speed of only 20, I could still manage to keep the torque.

It takes more current to make more torque. As long as your torque demand is low, you'll get more speed. But when you come upon a hill or more demandng terrain, you will slow down because the batteries or cables have reached their limit.

[70oldsracer]

Originally Posted by BobBoyce

It takes more current to make more torque. As long as your torque demand is low, you'll get more speed. But when you come upon a hill or more demandng terrain, you will slow down because the batteries or cables have reached their limit.

Thanks Bob. With what I have, is 16 mph pretty much where I should be? Although my sig line says 2 gauge cables, all of my cables are 2/0, except the 3 cables wiring the batteries in series and the one cable going from the battery pack + to the solenoid. I know my batteries are lacking in the AH department, but does that just effect my run time or will that also effect my speed and torque?

[BobBoyce]

Originally Posted by 70oldsracer

Thanks Bob. With what I have, is 16 mph pretty much where I should be? Although my sig line says 2 gauge cables, all of my cables are 2/0, except the 3 cables wiring the batteries in series and the one cable going from the battery pack + to the solenoid. I know my batteries are lacking in the AH department, but does that just effect my run time or will that also effect my speed and torque?

It affects everything, speed/torque/run time. I am suprised that you can get to 16 MPH... You must have really low rolling resistance!

Bob

[70oldsracer]

Originally Posted by BobBoyce

It affects everything, speed/torque/run time. I am suprised that you can get to 16 MPH... You must have really low rolling resistance!

Bob

Well, I put the recommended 20 pounds of air in my tires and I went through my brakes to make sure there was no unneeded drag. So, the cart does role pretty freely. Like I had said earlier, I plan on hooking up the lap top and going for a ride. How long should I drive it for and will it tell me if my batteries are lacking in power?