New alltrax controller acting funny...please help

[afairweather]

Hey guys i need some help here. I have an 06 ezgo 36V pds and my curtis 300 amp controller burned up the other day. I went out and purchased a new alltrax 400DCX controller upgraded all my wires to 4 guage and replaced the solenoid with a white rodgers heavy duty 200 amp. When i purchased the controller i had the guy program it with high torque and had him enable the turbo setting. After i installed it the cart ran amazing and very fast about 26 mph per my gps, BUT...now comes the problem. After about 15 minutes of riding the cart slowed down on its own and kept moving about 10 mph and then after about 2 minutes went right back to top speed. This has happened now about 5 times and happens even after i let it cool down and recharge the batteries. I have checked all my connections and voltage. I am getting about 37.6 volts from the batteries. Did i end up with a faulty controller or could my motor be bad now also? I am so confused and i cant seem to find anything on this topic. Please help if you can!! Thanks

[JohnnieB]

Welcome to BGW!

It could be hitting undervoltage cutback or it might be overtemp problems.

37.6V is only about 85% SoC, and the under voltage trigger point can be as high as 30V, so the pack voltage could be dropping that low if you are pushing it hard.
(Like we all do when we've got new toys to play with )

How does it run with with fully charged batteries? (38.2V measured 12 hours after charger shuts off)

What are the pack and individual battery voltages when it is misbehaving?

[afairweather]

so i contacted the people i bought the controller from and the guy told me to jack up the cart and run it to try and get codes off the controller. I did that for a min. until i heard a weird noise and i felt like the tires were spinning too fast. When i let go of the gas the tires spun by themselves and then the controller smoked badly and obviously quit working. I called him back and he told me that he is positive the motor is bad because that just never happens to an alltrax controller. Do you think he is right, and do you think that i killed the motor by running it with no load on it or it was already bad? I was not prepared to replace a motor, i plan on taking it off tomorrow to look at it. How will i be able to tell it is bad? Thanks for your help!!

[Spawn]

This guy sounds like a hack. HE should have never told you to run it off the ground with no load. Ya your motor is toast becuase of what he told you to do. You over reved it. You saw smoke from the controller? Why didnt you install a 400 amp solenoid? you upgraded the controller and cables but not the solenoid. That may be the weak point after your upgrades but I bet you need some rear end work now after running it on jacks.

[scottyb]

Originally Posted by Spawn

This guy sounds like a hack. HE should have never told you to run it off the ground with no load. Ya your motor is toast becuase of what he told you to do. You over reved it. You saw smoke from the controller? Why didnt you install a 400 amp solenoid? you upgraded the controller and cables but not the solenoid. That may be the weak point after your upgrades but I bet you need some rear end work now after running it on jacks.

You should never run your motor WOT without a load like this, even a stock setup will grenade or burn out in this situation. You got some bad advice, too bad it cost you a controller, the question is what's this dealer going to do about it? It sounds to me like he needs to take the controller back and refund since his incorrect direction is responsible for your controllers demise. The motor was going out but you should know this is not good for a motor either, so if you were running it WOT alot, especially down hill while getting those 'amazing' gps readings then that is what killed the motor off.
The alltrax controller lets you hit higher speeds by removing the rpm governor. Caution (or restraint) should be exercised.
P.S.
Shawn, a 200 amp solenoid is perfectly fine with a 400 amp control, that 200a solenoid has an inrush capacity of 800 amps, that's more than it will ever see...

[afairweather]

Just took the motor off the cart. Like we assumed the motor is toast. By looking at it i am willing to bet that it was on its way out but i probably sped up the process by running it no load. The dealer told me he willing to replace the controller under warranty. I am a little upset with the guy for telling me to do that but i am also mad at myself for not thinking before i did it. Now that i know i need a motor, do we have any recommendations? I want to stick with the 36 volts cause i dont want the added cost of the 48 volt upgrade but i want something that i can get decent ground speed out of and also will hold up. Also even if i get a better motor should i have him turn down the controller that he replaces. I dont want to have to do this again. I am about to start doing the research for the best motor now so any help would be awesome. Thanks for your input so far!! Oh btw i am lifted about 6 inches with 22 inch tires...if that helps.