DC to AC conversion

[Capt. Lenny]

I have a 2003 EZGO TXT series cart that I converted from 36 to 48 volts and am looking for more speed. You can see the cart details in my signature. Currently getting 27mph on flat ground with 2 people and a long straight away. I have not found where anybody has done this with a series cart so my questions are: is it possible to convert a series cart to an AC system? What can I expect for a top speed with an AC conversion?

[2K6TBSS]

I also have an 03 series cart and have been looking into the same thing.

I believe we would have to re-wire the cart with a PDS harness to go AC.

[ojo]

For a AC Drive you'll need at least a AC motor and AC controller, right?

[kernal]

This can be done and has been done. There are several carts in my area that were done years ago, long before the RXV or Navitas systems. As I recall they were expensive, $3K plus installation. One of these carts I have personal knowledge of. Know who owns it and see it periodically. Been running trouble free for years far as I know. Speed in the mid thirties on standard height tires. Its a Club Car DS and I don't know what the original drive system was but probably "series" because I think this was before IQ was introduced (about 2004).
I want to say these carts have HPEVS systems but I can't remember for sure. Don't see a kit from Navitas specifically for EZGO series drives but you might want to call them.

[bronsonj]

Your 225/35/12 tires should have an outside diameter of about 18.2" (if you can trust the manufacturer's numbers and if my math is correct). So 27.1 mph would be 6,000 rpm. Did Plum Quick say what the max rpm of their motor is?

According to the .pdf I see on the navitas motor it is good to 6,800 rpm or 30.7mph.

If your sole purpose is speed then the hassle doesn't seem (to me) to be worth it for 3 extra mph. If you just want AC or need the hill climbing abilities then it makes more sense.

[Capt. Lenny]

My math gave me 6064RPM which is close enough to yours. PQ said 6500 Max and you are correct, it's not worth the money for 3 MPH.

[Fairtax4me]

Look into the Silverwolf AC kit. Their motor runs 9,000 rpm.
Costs about $2k for the motor and controller, you would likely need wire harness and some switches, new cables, solenoid, etc. I'd think you could do the whole thing for under 3k if you did it right.

[Capt. Lenny]

Thanks. I did look briefly at the Silverwolf but that's a little too pricey for my budget at the moment. That 9000 RPM would really get the juices flowing!

[Capt. Lenny]

Did some more checking into Silverwolf and it doesn't look like they build motors for EZGO at the present time.

[Imapled]

Originally Posted by Capt. Lenny

I have a 2003 EZGO TXT series cart that I converted from 36 to 48 volts and am looking for more speed. You can see the cart details in my signature. Currently getting 27mph on flat ground with 2 people and a long straight away. I have not found where anybody has done this with a series cart so my questions are: is it possible to convert a series cart to an AC system? What can I expect for a top speed with an AC conversion?

Navitas TAC2 traction inverter and Navitas AC induction motor is the most common drop-in setup. 10's of thousands of installs. There are about 5-8 posts on the Golf Carts Modified forum on Facebook of people receiving and installing their kits.

I have done a pile of them. I have lost count. Easy drop in install on an E-Z-GO 95-current model.

From 95-TXT48 it is best to install a new wire harness. So if you have a series, DCS or PDS drive system on your TXT it is best to install a new main wire harness. The Navitas TAC2 traction inverter is only sold in the TXT48 main wire harness adapter configuration.

Now to your question: Top Speed

The 440 and 600 versions of the TAC2 traction inverter (aka Controller) will get you to the same top speed. The major difference is coupling current capability. Take off will be better on a 600 over the 440 and will get you to max RPM faster but, both will make it to the max RPM.

A Navitas AC inductive motor is safe to operate to 9000 RPM. Navitas will qualify this and does about 10 times a day on Golf Carts Modified and their Navitas forum on Facebook. Question is asked daily and answered daily.

Top speed depends on a number of factors:

1. Rolling resistance and reducing it.
2. Voltage of your battery setup and the weight of your battery setup.

For #1 to reach the maximum performance you need to insure that your brakes are not dragging, your wheels and various moving parts are spinning properly and your differential is not full of molasses for oil. Your roof, front windscreen and horrible and useless clay baskets will all impact the top speed. (I hate clay baskets.)

Now for #2 on a 48VDC nominal lead acid setup with #1 addressed you can expect to see between 33-35mph on 9000 RPM max on 23" tires.

To go to the 40-50 range you need a proper battery. See, the Navitas TAC2 traction inverter supports both 48VDC and 72VDC nominal configurations. That is a nice bonus that you don't get with other OEM traction inverters.

So, with say a 72VDC nominal lithium (at around the 80VDC fully charged mark) and with #1 considered and resolved you can hit around 50mph. Now, this is a lithium battery that is capable of 300a+ constant current with a max burst of 500a for 60s.

Cheers,
Greg