Temp ?s

[tiqueman]

I recently tried a new set up in a BJ26 since I burned my BJ components quite some time ago. I was running a china motor, 2045 on 3S, 60A esc and a 637 prop and it was only gps slower than the stock BJ set up on a 642. Visually, I couldnt tell a difference. Anyway, 2 days ago I swapped it w/ a Turnigy 3656 1800KV motor and put it back on 4S using a Turnigy 120A esc. I left the 637 on it for testing purposes. I set the timing at 0 degrees.

After one run of maybe 3 minutes, Batteries were at 96F and 101F, ESC was 103 and motor was 148F. Whats the general cause of only a motor running hot? I bumped the timing to the next interval which is 3.75 and it brought the temps down about 10 degrees. Am I on the right track doing this? Should I go to the next interval of 7 degrees?

Also, and ironically, This afternoon I got my Genesis back in the water after some minor mods and swaping the shaft out to .150. Im running it on an Etti 150 OPTO, 4S, 0 degrees timing and am using the stock 8XL motor. Temps were common from my BJ run. Batts were 101 and 102F, ESC was 112 and motor was 137F. A bit of smoked puffed out and she smelled a bit. I know its not the choice of motor but its what I have to use for now. Oh this was on a X440 prop and it ran teriffic!

I just want to find out if high motor temps when nothing else is warm is a timing issue or is it cheap motors?

Thanks,
Scott

[Rumdog]

Never use 0 degrees timing. try 7 degrees. I may want even more than that.

[tiqueman]

Coll Rum, thanks. Its amazing the difference of what is often read in literature compared to real world advice. I shall try 7 in the BJ tomorrow and bumb the Etti in the Genesis up to whatever the next setting is and go from there.

So is timing then more than likely the culprit of only the motor being hot?

[ReddyWatts]

Know the max watt rating of your motor and design your setup to stay within it. The batts and controller are running well within their max rating and staying cool.

[m4a1usr]

So as not confuse the new guys reading this post,......... 0 deg timing is quite fine on certain motors. If you own a Neu "D" winding, 0 is perfectly fine. Actually recommended. On "Y" winding motors you will need more. For more information as well as "the words from Steve Neu himself" search RRR and do not confuse what works on certain motors as the only way to set timing values for all ESC/MOTOR combinations. Its a very confusing topic that needs to be seen in the right light. DO your home work so you get the best performance.

John

[BakedMopar]

IMO when you don't load the motor enough it will run hot.

[tiqueman]

Specs for the motor in the BJ
TURNIGY brushless Inrunner

Spec.
Kv: 1800rpm/v
Power: 460W
Turns: 6
Resistance: 18
Idle Current: 1.9
Esc: 60
Battery Config: 3-5S
Length: 57mm
Width: 36mm
Shaft: 5mm
Weight: 260g

So 460W, what do I do from that info? What formula am I looking for?

[tiqueman]

IMO when you don't load the motor enough it will run hot.

I was wondering that as well and forgot to ask.


For John, Thats where Im going w/ this.. "doin my homework" I figure I can poke around w/ timing and find what works best, mostly Im curious about the abnormal temp difference compared to the other components.

[Fluid]

For more information as well as "the words from Steve Neu himself"

As far as that, here is what Steve wrote to me several years ago:

D winds : 0 - 4.75
Y winds : Normal {9.0 to a max of 15.0 }
You can use up to 20 degrees but keep a eye on the temp of motor and controller. The higher advance will give a bit more speed at the expense of higher current.

Here is what was posted on the NeuMotors site:

In general the "Y" wind motors work best with mild to medium timing. PWM rate can be pretty much any setting. "D" wind motors should always use the mild timing settings for better results.

The OP's experience with "0" timing is typical and exactly as expected. With no timing advance on most common BL motors the efficiency is very poor - that's why the motor gets hot. Like John says, you need to understand your motor's design and thus its needs.


.

[ReddyWatts]

Spec.
Kv: 1800rpm/v
Power: 460W
Esc: 60 amps max
Battery Config: 3-5S


So 460W, what do I do from that info? What formula am I looking for?

Watts / Volts = maximum AMPS to keep motor cool - recommended by manufacturer.

460 watts / 11.1volts = 41.4 amps max

460 watts / 14.8 volts = 31 amps max

460 watts / 18.5 volts = 25 amps max

[tiqueman]

Watts / Volts = maximum AMPS to keep motor cool - recommended by manufacturer.

460 watts / 11.1volts = 41.4 amps max

460 watts / 14.8 volts = 31 amps max

460 watts / 18.5 volts = 25 amps max

Thank you

[08gtrking]

what temp reader you guys use?

[tiqueman]

Ive got the blue Duratrax one.