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New to RC World; question about motors

New to RC World; question about motors

Old 10-31-2018, 09:02 PM
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Default New to RC World; question about motors

Hi !!

i'm a brand new member of the RC world and i'm looking for any informations, especially on esc and motors.

About motors, i was looking a couple days ago the ROAR approval motor's list and there's a sign on the Excel sheet that i want you to explain to me :

uH*

What does this sign represent ??? Can you give me an explanation of why this measurement (i think (i think it's that...) can be found on the sheet ??
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Old 10-31-2018, 09:39 PM
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Found it. But it’s way too technical for me.

*NOTE: The minimum inductance spec figures in microHenries for each Stock or Super Stock motor have been listed for each motor manufacturer. These values directly correspond to the inspected number of turns on each slot of the particular stator design for that manufacturer. These values are provided for fast, accurate and simple field tech inspections, and do not reflect any performance differences between motor manufacturers.


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Old 11-01-2018, 01:37 AM
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uH stands for micro Henry. it is a main value of a coil like Ohm is a value for a resistor and Farad for a capacitor.

The value is made by the amount of windings, thickness of wire and the metal inside the coil.
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Old 11-01-2018, 07:56 AM
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Can we think that if a motor have a bigger resistance, it will take less amps to make the same watts and by the same way, the battery will last longer ???
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Old 11-01-2018, 08:06 AM
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I’m sure on of the electrical engineering guys will be able to give proper answer. And on the high level of racing there’s seems to be a quest for every bit of possible advantage. But for the average owner, basher or racer I don’t think we’d notice. Best way to extend battery runtimes are with better throttle control. I can take same car with same battery and get as short as 8-10 minutes running nothing but full throttle. Or actually driving and get close to 25-30 minutes or longer.

Its easier to just stop a change battery.
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Old 11-05-2018, 11:34 AM
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Originally Posted by TheRay57 View Post
Hi !!

i'm a brand new member of the RC world and i'm looking for any informations, especially on esc and motors.

About motors, i was looking a couple days ago the ROAR approval motor's list and there's a sign on the Excel sheet that i want you to explain to me :

uH*

What does this sign represent ??? Can you give me an explanation of why this measurement (i think (i think it's that...) can be found on the sheet ??

Head over to the reddit thread ELI5 (Explain like I'm 5) In the search bar type inductance. There is a good thread in there from 3 years ago, that explains indictance, so you can understand better how its is measured and maybe how it relates to our motors.
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Old 11-09-2018, 06:43 AM
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Comparing inductance to resistance, think of it like this:

You are riding a bike with weights bolted on the frame and a parachute behind you. The parachute represents resistance and it affects your top speed. The weights on the frame represent inductance and they affect how quickly you can get to top speed.

Electrons experience the same thing. The greater the resistance in a system, the lower your current flow will be. The greater the inductance of a motor, the longer it takes the electrons to get moving and the longer it takes the magnetic field to build up and collapse. However, with that higher inductance (typically) comes a stronger magnetic field in the same way a bike with weights on it has more kinetic energy.

Unfortunately, you can't equate inductance directly with efficiency. Slotless 4 or 8 pole motors have very low impedance, but can be very efficient. Typical 2 pole motors have a much higher inductance, but can also be very efficient. The speed control and how you are using the motor plays a big roll in their efficiency.

Narrowing it down just to spec motors like 17.5 or 13.5, the lower inductance motors as of late are trading efficiency for power.
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Old 11-13-2018, 06:12 PM
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are you wanting to race or bash?
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Old 11-13-2018, 06:28 PM
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Originally Posted by Rckstar759 View Post
are you wanting to race or bash?
i race on dirt ovals.

I'm an electro-technician in my job and first thing to do before repairs, it's understanding the problems!!!

I also ran Modlites over the past 8 years, winning the club's championship in 2011 and 2012. Understand all the stuff came from it too.
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