Ezgo pds '07 19mph?

[Conradconrad]

Originally Posted by JohnnieB

Glad I was able to have helped a little.

1. Next time you replace the batteries, go to 42V. You'll have more torque and about the same speed as the PO has with a 48V TXT.

2. If you end up with a motor that has a speed sensor, upgrade to a XCT-PDS controller. It incorporates motor RPM data into the field mapping algorithm and you get better performance as well as the safety feature of RPM limiting the motor to a max RPM of your choice, up to 8000RPM.

I know from personal experience that driving downhill with foot on floor to see how fast the cart will go, can take out the motor, which in turn takes out the DCX controller. Very expensive lesson learned.

1) I have already set my mind to that this am actually when a battery change is needed. I believe all I will need to get a DPI 42V charger and change the SW180 solenoid from 36V to a 48V.

I also dont see my "ezgo powerwise qe charger" green led turning off like the instructions say it will, which is a sign of completion of the charge cycle which worries me a little. It stays lit as solid green which mean 100% but "supposedly" is to turn off to show completion.

2) I think I will probably send the current DCS motor for a PQ bandit as really 25-26mph is about the fastest I want the cart to go. Not sure what the gains are from a PQ bandit for the DCS.
--Right now range>speed, at least now that speed is up


What do you think is the fastest I should let the DCS motor "coast" down hill to prevent damage since mph can relate to rpms.

Thanks again

[scottyb]

I vote against the bandit upgrade for Ezgo Sepex. I had trouble with it more than once. I lost a couple of motors and controllers before I learned my lessons.

See and save attached instruction on running a 36v solenoid in a 48v system.

[JohnnieB]

Charger voltage has to match battery pack voltage and the DPI Accusense not only is one of the most reliable chargers out there, it is also the best bang for the buck.

From what I've read about a Powerwise QE, the LED will stay steady green until it is unplugged.

I don't know if a 48V SW180 solenoid will work at 42V. Check with Scotty. (But I see he has attached how to run a 36V solenoid with a higher voltage battery pack)
I use a 48V MZJ400 (400A continuous/1000A peak), which works at 36V, 42V and 48V. I didn't know what voltage I would end up with when I upgraded to a DCX, so I got a solenoid the would work with anything I was likely to go to.

As Scotty mentioned, a PQ Bandit might not be the best choice for your setup. They have better performance than a stock motor, but they are still in a stock motor case and have roughly the same heat dissipation as a stock motor. Heat kills motors.

Range is determined by Watt-Hours (Pack voltage times AH of batteries) stored in battery pack, regardless of what the nominal pack voltage is. I got 30+ mile range from using seven 245AH 6V batteries for 42V. YMMV

The cart is a direct drive system, so MPH is determined by tire height, differential gear ratio and motor RPM whether your foot is on or off the throttle. You most likely have 12.44:1 gears, but I don't know your tire height. Stock is 18" and I suspect your tires are pretty close to that based on the ~22 MPH you are now getting.

If your tires are 18" tall, staying under 26MPH going downhill will keep the motor under 6000RPM, which is the max I would spin that old motor.

I was spinning my stock PDS motor over 8000 RPM going down a long hill with wide open throttle, but the armature didn't explode until I lifted my foot near the bottom and the regen braking kicked in, so the failure was caused by a combination of excessive heat and high RPM.

[Conradconrad]

Originally Posted by JohnnieB

but the armature didn't explode until I lifted my foot near the bottom and the regen braking kicked in, so the failure was caused by a combination of excessive heat and high RPM.

Is that when you put your fingers in your ears like in the pic on the side?

[JohnnieB]

Originally Posted by Conradconrad

Is that when you put your fingers in your ears like in the pic on the side?

That is when I squeezed finger prints into the steering wheel and left a brown stripe on the seat-cover.

The armature frame and field shoes became one, the motor seized and the cart slid to a stop.

Smoke and sparks were coming out of the DCX400 controller until I flipped the Run/Tow switch, but 250A fuse didn't blow.

[Conradconrad]

Originally Posted by johnnieb

that is when i squeezed finger prints into the steering wheel and left a brown stripe on the seat-cover.

The armature frame and field shoes became one, the motor seized and the cart slid to a stop.

Smoke and sparks were coming out of the dcx400 controller until i flipped the run/tow switch, but 250a fuse didn't blow.

holy moly!!!

[Conradconrad]

JohnnieB

Forgot to mention, as I have come to the loose conclusion that my motor is DCS. That would explain the lack of regen/ increase in battery voltage upon "regen" kicking in you were looking for correct?

If thats the case should I be leaving the brake current setting to zero?

[JohnnieB]

Originally Posted by Conradconrad

JohnnieB

Forgot to mention, as I have come to the loose conclusion that my motor is DCS. That would explain the lack of regen/ increase in battery voltage upon "regen" kicking in you were looking for correct?

If thats the case should I be leaving the brake current setting to zero?

All SepEx motors can produce regen braking, but there are lots of variables. Battery capacity. SoC at time. Battery health. Motor RPM at the time.

You are getting some increased battery voltage during regen braking, just not very much.

After about 90 seconds at 100% throttle, the battery voltage was 35.5V and 3 seconds after the throttle went to 0%, the battery voltage was 37.1V, or a 1.6V increase. When I was running a stock PDS motor and a DCX400 with a 36V battery pack, the pack voltage would climb above 40V. My motor was spinning faster, so I don't expect quite as much increase with your setup, but more than 1.6V.

You ought to be able to feel the regen braking slowing the cart. Adjust the Brake Current to what feels good to you.

[Conradconrad]

Ok that makes sense, thanks!