EZGO TXT Lithium Upgrade

[PingEye3]

Jon Brendle - 2006 EZGO TXT - Lithium Pack Replacement
This cart has an Alltrax XCT 48400 PDS controller, Plum Quick Bandit upgrade motor, 20.5” Tires and Ausco Disc Brakes to stop it. It will squeal the tires and top out at 32mph. (Pic 1)
Pack assembled on the bench, power and charger connections (Pic 2)
Pack assembled on the bench, BMS and connections (Pic3)
Battery tray ready to receive the Lithium pack (Pic4)
Final Pack installation with On-Board charger. To the right is the 48-12V Converter and LED fuse box for cart lights and accessories. Original charger receptacle replaced with Marinco boat male shore receptacle with cover. Connect with extension cord. (Pic5)
More to follow:

[PingEye3]

Final installation of controller with solenoid mounted remotely for better access to plugs on controller, especially the USB printer connection. (Pic 6)
Dash mounted bicycle speedometer, very accurate. Distance traveled, Avg Speed, Max Speed, Travel Time. (Pic 7)
New dash plate with Voltmeter installed. (Pic
The best thing of all, NO MORE ACID TO DEAL WITH!!!!

[Volt_Ampere]

Nice!! What BMS and what Charger? I have a 14 module 120AH Lithium Setup in my Yamaha. I have been running mine for about 6 months now.

[PingEye3]

Hello VA,
The BMS is what Nick is now providing with his packs from HAC.
SD Technology Pt. No. BML-14 v1.03. We now have 5 packs running around our club. Three are 7 modules, mine is 14 modules like yours only split 6-8 (06 Precedent), the last one is 10m/5c paralleled for 41.2V fully charged. It is on a bone stock 36V TXT. Still only goes 20mph but has great range with the double pack and less weight. It is quite peppy and rides so nice when you get the LA battery weight out of the cart.
Gary

[scottyb]

Looking good.

205/40-12 tires convert to 18.5" tall so if my math is correct 12.44:1 stock gear ratio, 32 mph would be about 7250 rpm.

Does that sound right?

[PingEye3]

OOPS - Error on my tire size 215/40-12 need to change that. My cart is Precedent with the 12.3 ratio. Next week installing new 10.3 transaxle and Executioner motor. Isn't the 12.44 ratio EZGO. Earlier question: Charger is one of those Chinese models that Nick likes to use.

[PingEye3]

ScottyB,
Back to tires on TXT upgrade. They are 205/65-10 for the 20.5" tire and the 12.44 axle. That would be 525 axle rpm @ 32mph. Thus a motor rpm of right at 6500 if the calculator I use is correct.

[JohnnieB]

Originally Posted by PingEye3

OOPS - Error on my tire size 215/40-12 need to change that. My cart is Precedent with the 12.3 ratio. Next week installing new 10.3 transaxle and Executioner motor. Isn't the 12.44 ratio EZGO. Earlier question: Charger is one of those Chinese models that Nick likes to use.

Even 215/40-12 tires only work out to 18.77" tall. However, the numbers on the sidewall are very approximate and can be off by an inch or more in either direction.

So is the 20.5" tires mentioned in your first post the actual measured height of the tires on the EZGO 2006 PDS you put the lithium batteries in?

If so, the motor spins at 6527 RPM at 32 MPH.

The XCT logs motor RPM (they call it speed in the data log) as well as Field amps, so what is the field amps when you are running at about 6500 RPM in the log?

If it is dipping below 2A, you might want to start monitoring the motor temperature.

[PingEye3]

Yes JohnnieB, the EZGO tires are 205/65-10 so you are right on the 6500rpm. We will be doing some more monitoring soon and I will check that out. It is still on Turbo with the Bandit motor so we could be close to low end on field. In all of the high speed test runs 4 ga cables got warm (all high amp runs) but motor temp around 120°F even a few minutes after the runs.

[JohnnieB]

Originally Posted by PingEye3

Yes JohnnieB, the EZGO tires are 205/65-10 so you are right on the 6500rpm. We will be doing some more monitoring soon and I will check that out. It is still on Turbo with the Bandit motor so we could be close to low end on field. In all of the high speed test runs 4 ga cables got warm (all high amp runs) but motor temp around 120°F even a few minutes after the runs.

I forgot you lost 200 pounds or more in battery weight.
Apparently your motor isn't working all that hard at high RPM, so increased motor temperature due to aggressive field weakening may not be much of an issue with your setup.

When you record some log files I'd love to see some of them.
(Preferably in CSV format so I can load them into the Quattro-Pro spreadsheet I use.)