Motors ...for beginners - please keep it simple

[Ed Anderson]

If he is going to start changing propellers he should check it with a wattmeter.  The advice you just received is to go from a 9X4.5 to an 11X6.   That is a big prop jump.    

That might be OK or it might overload the motor, the battery or the ESC.    Once you stray from the MFG recommendations you must check with a wattmeter.    

I have seen too many crashes and too many buned up components due to people bumping up the voltage or changing the prop and burning something out as a result.   They cry foul and blame the components until I put my wattmeter on and find they are pulling 40 amps against a 25 am ESC and a motor rated for 30 amp.   

Poof and all the magic smoke comes out, assuming it doesn't start a fire.

 

 

 

 

Edited By Ed Anderson on 20/08/2016 21:24:38

[Peter Miller]

I know he hasn't got one. Maybe someo has one he can borrow, we do have some other electric flyers in the club.

[Tim Mackey]

It had already been stated in the o/p that his friend didnt have a meter. The thead title is motors for beginners keep it simple.
Im SIMPLY saying a 9" prop on 72" plain model is too small. Without knowing the exact motor specs - especially max current capabilities Its impossible to be sure. However, most decent sized 950 kv motors ive used or got are fine on a 12"prop and 12v.
Mind you - what do I know 😄

Edited By Tim Mackey on 21/08/2016 01:53:27

[Ed Anderson]

 

Whether the friend has a Wattmeter or not, if he is going to play around with props he should be checking the power with a wattmeter. Don't have one?

If he doesn't want to get one he should stay with the MFG recommended, which, in this case is a 9X4.5 as reported in the post.

 

 

 

 

Edited By Ed Anderson on 21/08/2016 02:46:04

[Peter Miller]

Thanks I will pass on both comments. As I have said, I know nothing about electrics, nor does my friend. Hence the original question.

I shall suggest thathe stays with the original prop and then try bigger ones if the performance is lacking.

[Ed Anderson]

That is a good approach.

 

Wattmeters are an essential piece of kit for electric flyers who are moving away from Ready to fly or bind and fly packages.   As you change props or battery voltage you change the power curve of the motor.   As a result you can overload something leading to component failure.  So you check with the wattmeter to insure that you are not overloading the motor, the ESC or the battery.

They are not expensive.   I have two.

Here is an example of a wattmeter from HobbyKing.

http://www.hobbyking.com/hobbyking/store/__14624__HobbyKing_PO_Wattmeter_100A.html

 

 

Edited By Ed Anderson on 21/08/2016 14:51:19

[kc]

A wattmeter will save it's cost the first time it saves an ESC!

[Tim Mackey]

Posted by kc on 22/08/2016 12:43:42:

A wattmeter will save it's cost the first time it saves an ESC!

Yup