Lipo-powered E300 does not start

[jotto]

Sorry for cross-posting this, but I got no reply on the stand-up forum.


I have a new Razor E300. I'd like to see better hill climbing, so I'm experimenting with various lipos. Apart from the batteries, everything is stock.

6S works fine (but with no additional power). With 8S or 9S, however, the motor does not start. I can just hear a click from the controller when I twist the throttle.

What can cause this? According to various forums, the stock controller should handle 36V without problem.

[kfong]

Not sure, I replaced the original controllers on two e300 with ones that had real throttle control. If you burned out the controller I can send you mine, just send $7 for shipping. PM me for details.

[jotto]

Not sure, I replaced the original controllers on two e300 with ones that had real throttle control. If you burned out the controller I can send you mine, just send $7 for shipping. PM me for details.

Thanks for your kind offer! I don't think the controller is fried though -- it still works with the SLA batteries and with 6S lipos. Which controller did you replace it with?

[kfong]

http://tncscooters.com/index.php?route= ... uct_id=177

You will have to replace the throttle if you go this route.

[jotto]

Thanks! Price is not too bad. Then I just need to find a throttle that fits the E300, too.

[kfong]

Any of the hall throttles will work since the handle is the same as a bike. Much better control vs. the on-off of the original.

[jotto]

Ok, so this one would work? http://tncscooters.com/index.php?route= ... duct_id=86

[kfong]

http://tncscooters.com/index.php?route= ... duct_id=82

This was the one I used. But I believe they all operate off the 5 volts.

[jotto]

Did you use the stock motor? What battery configuration?

[kfong]

I kept the stock motor. The voltage I kept at 24volts because both scooters were for my nieces, ages 11 and 13. I really did not want them to go fast. I also found these scooters to be very unstable at high speeds due to the short coupled steering. I also made a custom fuel gauge so they could tell how much capacity was left using my smart switch. It also does a power down if they forget as well as protect the batteries.

Some info on the fuel gauge here
viewtopic.php?f=2&t=22675&p=525604&hilit=+Jeremy+fuel+gauge#p525604

[jotto]

Cool, thanks (again)

[buzzfirst]

Hello, I would recheck the polarity of the 8s and 9s packs. If the controller sees reverse voltage it will shut down. Dont ask how I know.

[jotto]

Hello, I would recheck the polarity of the 8s and 9s packs. If the controller sees reverse voltage it will shut down. Dont ask how I know.

It's checked and double checked, but thanks

[SamTexas]

I don't think the controller is fried though -- it still works with the SLA batteries and with 6S lipos.

Have you tried 7S?

It sounds like your controller can detect too high voltage and prevent power from going to the motor. I have seen this behavior with two wheelchair controllers. They both run on 24V SLA. I swap the SLA with a 6S (25.2V max) and they work fine. Also worked fine with 7S (29.4V max), but would not work with 8S (33.6V max). So I partially discharged the 8S pack until the voltage hit 30.0V and it worked.

[jotto]

I don't think the controller is fried though -- it still works with the SLA batteries and with 6S lipos.

Have you tried 7S?

It sounds like your controller can detect too high voltage and prevent power from going to the motor. I have seen this behavior with two wheelchair controllers. They both run on 24V SLA. I swap the SLA with a 6S (25.2V max) and they work fine. Also worked fine with 7S (29.4V max), but would not work with 8S (33.6V max). So I partially discharged the 8S pack until the voltage hit 30.0V and it worked.

No, I haven't tried 7S. I don't have the batteries to make that configuration. The overvoltage detection theory makes sense, though. This is a brand new E300, so perhaps they started adding overvoltage detection in the newer revisions.

Seems like a 36V controller is the way to go. Can the tnc scooter throttle controls be used on a brusless controller? I'm planning to convert to brushless some time in the future. For this season, I will stick to the stock motor.

[jotto]

Ok, I just placed an order on a 36V controller and a throttle. Looking forward to testing it! =)