Alltrax controller

Um, Alltrax makes controllers rated for 48 volts and for 72 volts. While the Xebra owners are sometimes running their 72 volt alltrax controllers at 84 volts, I'd be leery of going past the rated values. What I understand from the Xebra owners is the FET's used in the 72 volt alltrax are actually rated for 100 volts. So an 84 volt pack (nominal voltage) would have a fully charged voltage near 95 volts. And while that's less than 100 volts, engineers like to put in safety margins in case the actual widget is under or overperforming in some way. To maintain safety margin engineers usually use components rated well over the expected range, just in case the specific component in the specific widget is weak (or becomes weak).

That means you might be able to take a 48 volt controller and run it at 60 volt (nominal) but it's probably not a good idea to do so.

As for me ... I've been having very poor luck with high power controllers. I've built a few vehicles at "low" power, often using the 4QD controllers. But I have two alltrax and one curtis controller where, during hookup, there was a loud spark, and now the controllers are nonresponsive.

- David Herron, http://davidherron.com/

Hi Amp_head,

I'm only using an Alltrax at 24 volts but sure haven't had any problems with the controller, at all.
Mine is the AXE4824 and it works sweet!
I do wish it were a bit smaller, but that's not a performance issue and may not be practical.
The ability to program it gives it a lot of flexibility.
I emailed Alltrax when I first got it to ask a question about my particular application and they responded immediately and answered my question.
So far, I'd recommend Alltrax highly.

So, I wish I could answer your question, I can't, but wanted to at least comment on my impression of their controllers.
I would not worry in the slightest, as long as you stay within the rated specifications.

Reikiman,
When you connected the lead and got the loud spark, you must have had something turned on that was drawing a fair sized load. Either that or the capacitor(s) were charged way up and discharged upon connection.
I had an unusual situation where I was checking my battery voltage and the meter indicated there was full voltage where I knew there shouldn't be any. :? When I kept the meter attached, I noticed it going down in voltage slowly then realized that it must be capacitors discharging ...
I know that Alltrax recommends a diode be placed across the coil of the solenoid. I'm not using a solenoid but if I were, I would have added one where they suggest in Quick Installation Guide. An ANN type fuse is also recommended.

Dave

MB-1-E
Electric - Bridgestone MB-1 Mountain Bike

The problem is that the wiring diagram delivered with the alltrax controller is very sketchy. It doesn't mention a diode, nor capacitor, etc. So the last one I bought (a 72 volt unit) I hooked it up (no solenoid etc) for a quick test, and was met by that loud spark. Hurm.. I afterwards went to the alltrax website and they've greatly improved the documentation since the previous time I'd looked a couple years ago. In addition to the sketchy manual that comes with the controller, there's an extremely detailed wiring guide in the documentation library. I really wish they'd delivered that with the controller!!!

- David Herron, http://davidherron.com/

Hi Reikiman,

I'll drop Alltrax an email and explain the importance of this and point out that some retailers may not be including the proper documentation. I received the infomation with my purchase, but it may be that some retailers are just not including it.
Electric Vehicles USA Inc. did include this information, as it should have, and I'm very happy with their service.

I realize that this won't help your situation, but perhaps save a future customer from having problems.
I'm sorry to hear that you had this happen, the Alltrax company seems to be a very responsive and caring business, IMO.
Have you asked them for a possible warranty replacement?

I bet that they will respond positively and insure that retailers include all relevant information.
I'll keep you posted on their response.

Dave

MB-1-E
Electric - Bridgestone MB-1 Mountain Bike