Working temperature of SS

[brushless]

In RCCarAction July issue, there was an article concerned about super sport brushless system.

The author used SS with 6.9:1 gear ratio in his TC3, the working temperature of the ESC was 240 F and the motor was 200 F.

He concluded that the gear ratio was likely the upper limit, as any further push may end up with break down of the system.

I use gear ratio of 6.5:1 in my Barracuda without any problem, and interestingly, although the ambient temperature in my local track was up to 36 C, the temperature of my ESC was < 80C and the motor was <70C, after unit conversion F = 9/5 C + 32, they were still significantly lower.

Also, based on my tragic experience for breaking down of the system ( 2 set already ), those coded temperatures were very dangerous indeed.

Any one want to share the experience in these aspect.

P.S. I use on-board digital thermistor with max temp recording capability and infrared gun thermometer to measure the temperature

[mcquto]

I use an infra red gun and I usually get about 180 to 200 on the speed control and about 150 to 170 on the motor. Thats running the reccomended gear ratio in a B4 buggy. This is after a 5 min. race, not a total battery dump. I would assume that after a total batt. dump with a 3000mh batt. it would be slightly higher but I have never had it thermal out on me. As far as your having 2 units go bad on you, I have bought 2 units that were bad right out of the box and had one go bad after 3 runs. The hobby shop replaced the 2 that were bad from the box and the third I sent to Novak for repair and they had it back to me within 6 days of my sending it! They compleatly replaced the speed control and I havent had a problem since. I have 2 Novak SS systems in my XXX4 and My B4 and they work great. Novak really stands behind their product.

[crono man]

i got 240F after a full 3000 pack dump on a tight track were i used the reverse alot,now mind you because of the tight fit between the body and the chassis in a xxx buggy theres ZERO air-flow inside a buggy.So i made a small air scoop right above the heatsinks and now i get in the low 160F.
my ratio is about 9,5;1

[cpb]

Here's what I got from emailing Novak back on 3/27/03. Things may have changed since then, so use at your own risk.

"Normal operating temps in the Un-Limited modes is close to 170F. In the limited mode the ESC gets "A Lot" hotter. We do not have the temperature data for the Limited mode available right now. We've brought ESCs off the track at up to 200F and had them continued operating properly. Get too much above that and parts start to fail."

edit: Those temps are at the ESC heatsink. The motor temp shouldn't matter per se, since there's not friction except for the bearings.

[atm92484_3]

If I can still grab the heatsink after a run and it is barely past 100 degrees, is it safe to assume that I can still go up a few teeth on the pinion?

[brutesparkfist]

Originally posted by atm92484_3
If I can still grab the heatsink after a run and it is barely past 100 degrees, is it safe to assume that I can still go up a few teeth on the pinion?

probably. 100 degrees F is not very hot.

[k_sw31]

I have found a small computer fan is the best thing for cooling down rc electronics.

I installed one on my hacker master competition...before hand I beleive it was running at probably 200 degrees or so; it wasn't hot enough to boil water. After the addition of a cooling fan, I would be suprised if it is above 100 degrees after a full 3000 mah dump, running a basic 5300. Even running 8 and sometimes 10 cells, it isn't all that warm.

Keep in mind I don't need the fan, but I feel a hell of a lot better about it. It's basically 12$ insurance on a 260$ controller.

Probably the best 12$ I'll even spend at radio shack...I'm also considering making a custom mount to run one on my motor...keeping EVERYTHING cool, making for back to back pack runs a breeze.
http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F011%5F002%5F007%5F002&product%5Fid=273%2D240