EZGO Txt Upgrade cont

[JohnnieB]

Here are examples of the Throttle's Linearization, Speed and Torque curves that tell the controller to go to 100% duty cycle when pedal is less than flat on floor.

[IRwynn]

Johnnie and Scottyb,
Attached is the monitor log from this morning, I performed a test last night and the log file was corrupted , by that time is was dark and the cart has no lights yet so I waited until this morning.
A couple of things I noticed.
1) The batter voltage shown on the controller is less then the measured voltage from the pack, for example the monitor showed 47.5 volts but the pack measured 49.7 volts. 2)With the cart on jack stands, the pedal at full throttle the led turns orange after several seconds (sometimes). I try not to keep full throttle on the stands for long.
3) While monitoring on the street this morning at full pedal the monitor showed 85% throttle the speed at 85% was 16mph. Once I briefly saw 100% but it did not hold and I did not see the mph.
4) the cables S1 and S2 did get warm at the F&R switch after running the cart for a short time. No other cables got warm.

Last evening I took apart the rotary portion of the F&R and cleaned the contacts on both sides. The was no appreciable dirt or corrosion visible.

I really appreciate the help and advice from you both

Richard

[JohnnieB]

1. There is a 470Ω resistor between the solenoid's large terminals, so when the solenoid contacts are open the voltage on the controller's B+ terminal will be a few volts less than the voltage at the battery pack. Only after the solenoid clicks (contacts close) do the voltages at the battery pack and controller become equal.

2. & 3. Try clearing the throttle's auto cal. (see attached)

4. Clean the cable connections.

5. The zip file is empty!

[IRwynn]

I used 7z, try this one. Will clear and let you know

[JohnnieB]

That one came through.

Your handheld DVM might be reading a bit low (replace battery). The log shows 48.2V before solenoid clicked the first time and 50.8V after it clicked.

The first throttle entry was 92%, but only for one line and never got over 88% after that and only two lines of 88%.

In the two time periods over three seconds in length the throttle settled into the 74% to 77% range (mostly at 76%) during the first and in the 82% to 85% (mostly 83%) range during the second.

First run:
7:48:12 to 7:48:21 (9 seconds)
Took 2 seconds for throttle to stabilize at about 76%
Throttle erratic. 48% to 8% to 43% to 40% to 47% to 57%. Should have increased smoothly to max.
124.5A max battery amps. Better, but still low.
Battery voltage nulled to 44.7V


Second run:
7:48:41 to 7:48:57 (16 seconds)
Took 1 second for throttle to stabilize at about 84%
Throttle ramped up smoothly.
217.3A max battery amps. Probably be 300A or more if throttle went to 100%.
Battery voltage nulled to 41.3V

I'm seeing throttle issues (erratic up ramping and not going to 100%) and battery issues (9V drop when 217A drawn).

[IRwynn]

JohnnieB, Cleared the Auto cal as suggested. Looking at the monitor I still only got about 85% throttle while riding. I changed the throttle setting so at 85% throttle I would get 100% speed. Now on a flat road I get 18/19 mph.
Checking battery, motor and F&R connections after running and nothing seems to be getting warm or hot.

[JohnnieB]

Still something flakey about the throttle. Don't know if it is the ITS sensor, controller or the wiring.

However it is going to 100% now and you're getting ~19MPH, which is a little slower than expected for your setup. Maybe something mechanical is holding cart back. Dragging brakes, dry wheel bearings, dry bearings in motor or differential?

[handtools]

you're getting ~19MPH, which is a little slower than expected for your setup

Just as a reference, my series cart is set up very similar and top speed is 17-18.

[JohnnieB]

Originally Posted by handtools

you're getting ~19MPH, which is a little slower than expected for your setup

Just as a reference, my series cart is set up very similar and top speed is 17-18.

Theory yields to reality.

I was basing my guesstimate on a 22% speed increase from the 22" tall tires and a 33% speed increase from upping the battery pack from 36V to 48V.

Stock is 14MPH, so tires ups that to 17MPH and batteries ups that to 22MPH.
The tires lost about 18% of the torque, but the batteries gained 33% in the torque department, so the net torque gain is about 15%, which ought to close the usual gap between theory and reality, but it appears that it doesn't.

[IRwynn]

Just a quick update, tried adjusting the slide tube and no effect, it was liightly short of the end of the ITS, no change. I replaced the ITS set my throttle curves back to standard. Now I get 100% throttle I expect. Speed is a bit better on the top end I hit 20mph.