Help! ESC and motor compatible?

[Friaar]

Hey guys, i realise this is a very newbie question but i just want to be sure. I crashed my apprentice and the motor is bust, so i want to buy a new motor that's compatible with the 30amp esc and im wondering if this motor would work: https://hobbyking.com/en_us/turnigy..._en_us_products_hbk_price_stock_7_group_0_asc

Im not sure as on the site it says esc between 30-35 is it safe to use with a 30 amp?

Also, do this (or most) motors fit with most motor mounts? as i cant find the specs of the apprentice motor mount.

 

[Merv]

Yes, I think it will be fine. The idea is to use a prop that will not exceed the 30a limit of your ESC
If you look at the prop data, it’s drawing 19.5 amps with a 11x4.5 prop on 3S. The question is what prop are you using and what battery cell count are you using?

A lot of motors use the same mounting hole pattern, can’t say for sure about your situation. You may need to drill new holes.

 

[Friaar]

Yes, I think it will be fine. The idea is to use a prop that will not exceed the 30a limit of your ESC
If you look at the prop data, it’s drawing 19.5 amps with a 11x4.5 prop on 3S. The question is what prop are you using and what battery cell count are you using?

A lot of motors use the same mounting hole pattern, can’t say for sure about your situation. You may need to drill new holes.

Im using a 3s, and already got an 11x8 prop, but i could just change it. Is there a way to calculate the amp draw for a specific prop or do you think it would be fine with an 11x8?

 

[FDS]

You look at the motor data sheet, it has power draw by prop size. A steeper prop pitch will draw more amps peak.

 

[Friaar]

You look at the motor data sheet, it has power draw by prop size. A steeper prop pitch will draw more amps peak.

Yeah but it only has these values:

Test Data @ 11.1v:
9x5 - 8.6A - 650g Thrust
10x4.7 - 11.5A - 860g Thrust
11x4.7 - 19.5A - 1140g Thrus

 

[FDS]

Then it doesn’t recommend a steeper prop pitch for that motor. It will probably get too hot with a steeper pitch.

 

[Merv]

Looks like the HK motor is rated up to 28a. My guess, it will work but I cannot guarantee that it will.
The stock motor was working on a 30a ESC. I’m guessing the larger prop will draw less than the 28a rating of the motor.

What Kv is the stock motor? Is it lower Kv than the HK 850 Kv motor? If the HK motor is higher Kv, it will spin faster and make the prop draw more amps.

 

[quorneng]

That motor is rated for 28A max so it should be ok just! with an 11x8 but it would depend on how well the motor (and the ESC) are cooled.

Of course by far the safest way to find out what the Amp draw is to get a Watt meter. They are not expensive and will pay for itself instantly if it stops you 'frying' something!

 

[Sero]

Should be fine with the 11x8, but if you're ordering the motor why not grab some different sized props with it? Also with Hobby King read through the reviews to see what props others are using with the motor your looking at. Lots of info on the motor your considering in the reviews.