Magnetic against optical solution

[sensor123]

Hi,

maybe someone can help me with the following topic:

What are the pros and cons regarding optical sensors (infrared) compared to magnetic sensors (especially Hall sensors)?

Thanks in Advance

 

[sensor123]

Application is a Steering angle solution. Question now is, if the optical solution provides better handling opportunities than the magnetic one. There are deeper specification which are not needed for a general answer to this question.

 

[MikeHalloran]

Hall sensors are remarkably temperature sensitive. If the application is digital, it's not a problem, unless a little threshold drift bothers you.

ABS systems seem to universally use a permananent magnet and what I think is a reluctance sensor. It works well, until iron filings foul it.

Optical sensors are generally sensitive to infrared, so a nearby heat source (e.g. an exhaust manifold) might blind them. I've lost count of the number of times that my sparky friends have tried to use plastic tonewheels with optical interrupters, and eventually, after expending large sums of money and time, learned that most plastics are transparent to infrared. You need at least a thin layer of metal foil to stop the radiation. Really arrogant sparkys demonstrate that their chosen sensor works with platic interrupters, then are surprised when the next lot or next year's production model doesn't.


I don't know what you mean by "better handling opportunities", in the context of a sensor.



Mike Halloran
Pembroke Pines, FL, USA

 

[BobM3]

Optical sensors are sensitive to dirt.