Losi five-T brushless with custom body panels (T-Rexx)

[othello]

Thanks guys. It is a blast to drive. Despite the weight it is still a very sturdy platform. Not much to wrench since around 28 runs. Only the bearings in the rear wheel carrier can get stuck when i drive in the wet ... aside from that nothing.

I have now protected the bearings. Let's see if that helps.


I have made a small upgrade to my motor cooler


I have replaced the 0.8W and 1.2W fans with two 2.5W Sunon fans which has improved air flow significantly. Both fans are now better protected against stones and stuff. Since there is a lot of amps/power displaced by the castle 2028 motor (between 1.7 to 2.5kW average during a run) i'm trying to keep the motor in its comfort zone. I don't really know how efficient this motor is but let us assume it's averaging 85% then there is still a loss of 255-375W in heat which has to be removed.

This setup (with 8s) really is only for fun driving and i'm mostly driving with a short brake during a run (after 4-5 minutes) to check temperatures and giving the components the opportunity to cool off somewhat.

[Pdelcast]

Originally Posted by othello

Thanks guys. It is a blast to drive. Despite the weight it is still a very sturdy platform. Not much to wrench since around 28 runs. Only the bearings in the rear wheel carrier can get stuck when i drive in the wet ... aside from that nothing.


I have replaced the 0.8W and 1.2W fans with two 2.5W Sunon fans which has improved air flow significantly. Both fans are now better protected against stones and stuff. Since there is a lot of amps/power displaced by the castle 2028 motor (between 1.7 to 2.5kW average during a run) i'm trying to keep the motor in its comfort zone. I don't really know how efficient this motor is but let us assume it's averaging 85% then there is still a loss of 255-375W in heat which has to be removed.

This setup (with 8s) really is only for fun driving and i'm mostly driving with a short brake during a run (after 4-5 minutes) to check temperatures and giving the components the opportunity to cool off somewhat.

The 2028 at those power levels is around 88% efficient. (assuming that's the older 2028 -- the newer version of the motor is quite a bit more efficient.)

Thanks!

Patrick

[othello]

Thanks for clearing that up. Bought the motor feb 2014. How to differentiate between the old and new version?

Any thoughts about optimising cooling of the xl2? Is a higher voltage version of the xl2 still on your roadmap?

A bigger 2028er would also be an interesting option. Not much choice for big 4wd cars.

[othello]

I synced the xl2 log data (imported them into the eagletree software) with a new running video of the losi.

Preview picture


The data inserts are partially in german but i think everything is self-explanatory
-> Drossel = Throttle
-> Strom = current

Enjoy the additional inserts while watching the Losi (69mb mp4 video)

XL2 Log viewer graph of this run


Temperatures collected after this run (outside temperature: 32°C // 89°F)
- Motor: depending on the measured part of the motor: 62-74°C // 143-165°F
- SLS battery packs: hottest point 53°C // 127°F
- Turnigy uBEC: 52°C // 125°F
- Center Diff and outdrives: 52-60°C // 125-140°F