3 ESC (VESC) Mounting Questions

New Guy Doing New Build Question:

3 questions regarding mounting of the ESC for my first electric mountainboard build (MBS 95 Board with 9" wheels, dual Flipsky 6374 motors, belt drives, 12s4p battery mounted in pelican case, Flipsky Dual Big FESC 6.6, 190 pound rider):

  1. Does the ESC need to be rubber mounted to isolate it from vibration?

  2. Can the ESC be place inside a sealed waterproof pelican case with no ventilation or should it be mounted where it receives air circulation?

  3. How close does the ESC have to be to the motors (e.g.: can it be mounted inside the pelican case in the middle of the mountainboard or is there a reason most ESC are mounted on the tail of the skateboard, just inches from the motors)?

Bonus Battery Question: Should I ventilate the pelican case holding the battery pack (I estimate the interior temperature of a sealed black pelican case in direct sunlight on a hot 100 degree fahrenheit summer day would be around 135 to 150 degrees)?

I appreciate input from anyone with experience addressing these operational and engineering challenges.

Thanks in advance,

New Guy

Welcome.

Some good questions.

  1. No it doesn’t need to be rubber mounted, but over engineering can’t hurt… Assuming the larger non smt parts on the pcba, that can vibrate, have a glob of glue on them to mechanically support them it should be robust in high vibration environment.

  2. Yes, it can be fully sealed. However it is definitely going to cool faster if there is airflow. A really well designed, large mass, heat sink can suffice. Can’t be sure the flipsky falls into that category. Focbox unity should handle it ok as i have personally seen them working very well in high power MTB boards like lacroix and kaly, bioboards etc.

  3. Technically it should work, however there are some losses the longer they are. Aesthetically, really long phase wires are just bulky and annoying, especially if you also have 6/12 sense wires in the same bundle. It also opens the door for more issues/faults, also wire is heavy and adds cost. My advice, Make them long enough that there is enough strain relief between the esc when at maximum turning radius, but as short as possible. Hence the rear-mounted design so common in most builds.

Don’t leave your battery in the sun, try to keep it in a cool place when possible. If your battery is getting too hot during discharge you need to lower your current draw or make a bigger pack.

A dedicated vent in the box is probably not worthwhile but nor should you try to create a total air lock. Some ability to vent is good, as long as you dont create a hole for liquid ingress. Find a balance between the two.

Onloop,

I appreciate all your answers and suggestions; they were very helpful. It should be an interesting challenge to balance the operating environment of a mountainboard (heat-loads, water-resistance, vibration, impacts, dust, mud, etc.) against the delicate-nature of the available electronics and batteries.

Cheers,

New Guy