Troubleshooting MP3 new build

[TomP]

To the MP3 bright minds,

Hoping someone might be able to shed some light on this one... I posted about a dozen messages below this with topic 'Extending cable on MP3'. I've since gone and extended the cable using j45 serial cable as instructed from motor to connecting hub and connected everything up. Indicator lights on throttle light up and show full, as do indicator lights on LiFePo4 battery pack but when I push down throttle lever nothing happens. Battery is fully charged. I don't have cruise control function plugged in but I'm guessing that's not a problem. I bought the motor secondhand, the previous owner demonstrated it working when I bought it. I haven't opened up the throttle mechanism or motor to check controller as I'm hesitant to do so as a newby with all this stuff.

Attached a couple of pics (still a work in progress just impatient to see the wheel go around!)

Any tips, advice most welcome.

Thanks

Tom

[Aliasssss]

Hello mate.

In the last picture it seems to me that the left brake lever is in the ON (squeezed) position. It couldn't be that simple could it? Keep in mind that for the regenerative breaking to kick in you anly need to squeeze the lever about 1cm from the free position, depending on your setup and breaking cable length. Try lifting the rear tire off the ground and try rotating it. Does it rotate freely or you encounter some resistance when turning? Once you spin the wheel it should rotate freely for a few seconds if it's not then the regenerative breaking is ON.

To test the motor you don't need to have any of the breaking handles connected. Try throttling the motor up without connecting the breaks. If it works then the problem is most likely one of the break levers. While disconnected try measuring the break levers wires with an Ohm meter. If there is continuity between the 2 pins then the break lever is most likely squeezed (brake is ON). If the lever is not visibly squeezed then there is a problem with the internal contact.

If nothing works try disconnecting everything and reconnect again. First connect ONLY the throttle plug. Then connect the DC motor plug to the battery. There will be a big spark every time you connect the main power plug to the battery. Do not worry, that spark is normal because the internal capacitors are charging very FAST, hence the big spark!

If that doesn't work you need to check the controller setting. If using the internal one I hope you do have the USB connecting cable and you need to use the GM software. There you need to check the voltage to which the controller is set to work. It can be 24v, 36v or 48V. I'm not sure what is the voltage of your LiFePO4 battery? If you have the controller set to work on 48v and you only have a 24v LiFePO4 battery then the motor wont spin up ... I think. Not sure, because I only use a 48v (53.6v fully charged) battery and thus my controller is only set to use 48v.

Hope this helps.

Please do keep us posted. Cheers mate!

[Bikemad]

Tom,

It won't be the controller voltage setting as you is using a 48V battery, and the motor should run with the controller set to 24V, 36V, or 48V with that battery.

As Aliasssss has already mentioned, both of the brake levers need to be fully released for the motor to work, and because you don't have any brake cables fitted, both of your levers have the cable attachment pieces stuck between the lever and the lever mounting bracket, which is preventing the levers from releasing fully.
This will definitely cause the brake switch contacts to close and the motor will be unable to run until both brake switches are open (lever fully released).

I would strongly recommend testing the motor with the rear end of the scooter placed on blocks to keep the wheel off the ground, just in case there is an intermittent problem with one of the throttle connections and the motor decides to suddenly start.

Wanting to see the wheel go round is understandable, but watching the scooter suddenly take off at full power on its own might not be quite so satisfying. 

Alan
 

[TomP]

Jeez you guys are good!

Thanks a bunch for the tips. The brake lever solution makes perfect sense. Hopefully that's all it is. I'll check it when I'm back on the mainland in a couple of weeks where the scooter is.

Alan, I did have the back wheel of the ground about half an inch when trying to get it going. It was resting on a crappy old pot which didn't look very photogenic!

Thanks again you guys. Hopefully I can repay the favor to others starting out one day once I get my head around it a bit more! I'll keep you posted.

Tom
Sumatra, Indonesia.