hallsensor: how fast?

[Lip]

Hi,
I would like to know the max fequency of hallsensors. In the description it say´s that hallsensoors are slower than magnetic sensors. But how fast are they?

My intention is to use a trigger wheel on the crank. The engine goes up to 8.000 rpm.
Is it possible to use a hallsensor
- triggered by a whell with 36 teeth = 4.800hz @ 8.000rpm
- or also triggered by a whell with 96 teeth = 12.800hz @ 8.000rpm?

Does anyone know?

Thanks

Philipp

[killerbee]

The one Hall sensor that I am familiar with is the Honeywell GT101. The specs are listed in the following links:

http://sccatalog.honeywell.com/pdbdownl ... t101dc.pdf

http://dkc3.digikey.com/Media/PDF/Data% ... 0ERIES.pdf

In the second link the maximum RPM quoted is 3600. There are some other limitations quoted on the spec sheet that you should look at.

[Lip]

Hi Killerbee,
thanks very much for reply.

This sensor seems to have an operating speed of 100khz in case you consider the other specs like tooth width and tooth spacing. Thats what I need.

Thanks for information an best rergards
Philipp

[MarkMc]

Hi Philipp,
You are correct in saying the tooth spacing and shape will come into the equation. I would not use a GT101 on a 36-1 or 36-2 setup if you are planning to rev to 8000rpm. Some of the new engines coming out these days can have high tooth counts and Hall sensors, like the newer Chev V8s which have a 60-2 crank trigger with a Hall sensor. I think you would need to be very careful about tooth size and shape.

My recommendation would always be for a magnetic sensor as they are much more reliable.