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Old Dec 30, 2008, 05:52 PM
hmmm...
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Difference between sensorless and non sensorless brushless motor?

what is the difference?


I heard people saying sensorless brushless motors being more fragile or prone to breaking in crashes then non sensorless brushless motors, is this true?
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Old Dec 30, 2008, 08:47 PM
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Well sortof. THe reason they are more prone to breaking is the sensor cut or torn. The only difference is that the sensored ones always knows where the core is so the motor will never cog.
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Old Dec 30, 2008, 11:55 PM
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In brushless MOTORS & ESC you have 2 different types, SENSORED & SENSORLESS. Sensored motor as a sensor to help the sensored ESC know the orientation of the motor shaft.

You can used both SENSORED & SENSORLESS motor with a SENSORLESS ESC.

But you can only use a SENSORED motor with a SENSORED ESC. When using SENSORED ESC & motor, the 3 motor to esc main wires have a VERY DISTICTIVE way to connect to each other and there is also a additional smaller tab of wires that connect both of them.

When using SENSORED motor with SENSORLESS ESC, you simply plug the 3 main motor to esc wires and leave the other smaller wires unpluged.

This is what can go wrong with a sensored motor, the sensor its self is something else that can break or malfunction.

SENSORED setup will have no COGGING of the motor, cogging is what happens when a SENSORELESS ESC is trying to findout the motor shaft orientation.
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Old Dec 31, 2008, 12:26 AM
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but cogging doesn't always happen on a sensorless esc
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Old Dec 31, 2008, 07:13 PM
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which is better?

I know some races don't allow sensorless setup.
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Old Jan 01, 2009, 03:32 PM
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imo sensorless is better. I'm just glad my track embraces Castle products.
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Old Jan 01, 2009, 11:20 PM
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Quote:
Originally Posted by mtfly2000
imo sensorless is better. I'm just glad my track embraces Castle products.
Yes, That's why I asked. I also use Castle stuff only. I am used to them and they're fairly easy to use and maintain
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Old Jan 02, 2009, 07:14 PM
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BETTER in what sense, better for you, or better in general ( specs ). A sensored system is better in that the esc knows the orientation of the shaft and start delivering power better. ( virtualy no cogging ) BUT in sensored motor, more stuff can go wrong or break.
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Old Jan 14, 2011, 12:22 AM
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Sensorless Motors are just as good and more robust

Quote:
Originally Posted by freechip View Post
BETTER in what sense, better for you, or better in general ( specs ). A sensored system is better in that the esc knows the orientation of the shaft and start delivering power better. ( virtualy no cogging ) BUT in sensored motor, more stuff can go wrong or break.

I beg to differ here. Sensorless motor drives actually use complex Clarke and Park transforms to determine the shaft positions. These are used to START a real aircraft turbine. I don't believe they would be using them there if cogging were to really happen.

Motor drive algorithms are getting more interesting with their complexity also on the rise. Sensored motor drives have the problem of "physically locating" the sensors. Any reason the placement of the sensor goes inexact, you lose efficiency of driving the motor. Sensorless systems are advanced enough to determine to a much better resolution, the position of the shaft, which in case of a sensored one, would require multiple sensors to determine the shaft position. Moreover, the sensors are most effective when the shaft begins to turn, while their static readings can be interpreted in multiple ways. Good for small load drives. Not for large systems.

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