Hot controller

[MarkLyons]

Hello
I have a 10 kW motor in a dirt dike with a VEC500 controller.
After a 10-15 minute ride with the controller pulling 50-100 amps with 5-10 second bursts at around 200 amps it gets really hot. The aluminium base being too hot too touch.
How hot is safe.
Is the aluminium base solid, could drill holes for water cooling.

[MarkLyons]

I should also say the motor gets bearly warm under same conditions

[Bikemad]

Hi Mark,

The base of the controller may well be solid, but I suspect it will already be drilled and tapped in certain areas for the screws that secure the PCB and the plastic cover onto the heatsink.

I would suggest fitting a separate water cooled heat sink plate to the underside of the controller:


Perhaps the high controller temperature could be due to the motor being insufficiently geared down for the bike.

If the gearing is too high, the controller and motor could be severely overloaded at low speed, resulting in excessively high current draw causing the high controller temperature.

If the controller gets too hot, I would expect it to cut out with an 11 blink/beep error code also being displayed.

Alan
 

[MarkLyons]

Thanks Alan
The gearing feels about right.10t front 57t rear. 18” wheel. Top speed is 100 kph, really strong to 85-90.
Just did a 15klm run around a steady 80 kph and heat was ok. Think I’ll try some finned heat sinks.