Magic Pie 4 dual driver

[Vipermn]

Hello. I am kinda new to this forum so if this is the wrong place to be please let me know. I have a problem  I hope somebody can help me with. I have a 48v dual drive on a Trek full suspension MB. When I go up a hill then stop, if I twist the throttle too fast to take off my battery shuts down and I need to turn the key off then back on again to restart the battery any idea what causes that?

[Bikemad]

The combined power demand from both motors under full load is simply too much for the single battery to deliver, and this is overloading the battery's BMS and causing it to shut down.

If you have the USB programming lead, take a screenshot of the existing settings for each controller before gradually reducing the "Battery drawn current" and/or "Rated phase current" until the cutting out stops.

I would suggest setting the front wheel current settings lower than the rear, in order to reduce the chance of wheelspin on poor or slippery surfaces.

As the cutting out only occurs during hard acceleration on a hill from a standstill, reducing the "Acceleration" setting alone might be all that is necessary to eliminate the cutting out problem.

Alan
 

 

[Vipermn]

Hi Alan. Thanks for the help. When I Try to read the stats with my laptop running Windows 7 the com ports do not show up. I installed the usb drivers but device manager says that "USB Serial CH340(COM4) has a yellow flag and when I read the properties it says that it might have a corrupt file blablahbla.

[Vipermn]

Hi Alan. I read the post "Programming Vector Controller " however I do have 2 usb 5pin cables sent with the motors but I can't get the drivers to install. The error says"Windows can not find the correct digital signature" or something like that. Is there another driver for that cable?

[Bikemad]

Try downloading the driver direct from the GM website and extract the CH341SER.EXE program from the USB-Driver.RAR file and place it on your desktop.

With the USB cable plugged into the PC, go to device manager and right click on the USB-SERIAL CH340 port and then "Uninstall" it, making sure you check the option to "Delete the driver software for this device." before clicking the "OK" button. You may have to reboot the PC to complete the removal.

When it has been completely uninstalled, unplug the USB cable and then run the CH341SER.EXE program from your desktop before plugging the USB lead in again and hopefully Windows will then be able to install the driver correctly.

The cable will hopefully be recognised and the COM port should then be selectable from the drop down menu within the program software, even if the cable is not connected to the controller.

Please let me know if removing and reinstalling the driver software solves the problem.

Alan

[Vipermn]

Hi Alan. Man, it sure is great all the support you contribute! Thank you very much! Now Before I read your most recent reply I switched laptops and everything went just like it was supposed to so now I am at a point where I need to know what how much I should attempt to adjust first. If I ride conservatively no problem, but I ride full throttle for a while when I come to a stop and then twist the throttle full on power drops out-hill or flat ground. If I twist the throttle slowly no problem. So which should I adjust first and how much? Thanks for the help Also when you say adjustments are saved does that mean to export them?

[Bikemad]

If you start by reducing the acceleration on the front motor by 20-40% you may find that this will completely eliminate the cutting out.

If the battery then starts cutting out after the first few seconds of acceleration, you will have to reduce the  "Battery drawn current" and/or "Rated phase current" on a trial and error basis until you find the settings that work best for you. It might be better to try reducing just the front motor settings instead of both, as this will ensure you still have maximum power on the rear wheel where maximum grip is available due to the weight distribution.

What you are basically trying to achieve is preventing both motors from drawing peak power at the same time. By reducing the "Acceleration setting on the front motor you will delay the power going to the front motor, which should allow the bikes speed to increase (which will automatically reduce the power going to the rear motor) before the front motor reaches its full power settings.

Also when you say adjustments are saved does that mean to export them?

To save the settings to the controller you must click on the "Download" icon, as the "Export" icon only saves a file to the laptop's harddrive, and I haven't had much success reloading (Importing) saved files.

Alan
 

[Vipermn]

 Hi Alan. Well you were right on the money. I worked my way down to 60 on Acceleration and  now I have an unbelievable bike. Thank you so much for your help. You are truly THE expert on these motors. I have a question off subject- If I wanted a little more top speed what is the best approach.....Thanks again for your help.

[Bikemad]

The speed is usually controlled by the battery voltage, and as you are already using a 48V battery, the only way to easily increase your speed would be to replace your existing front wheel with a high speed MP4, this should give you more speed but slightly less torque than you have at the moment.

Alan