# Brushless Hall sensor frequency calculator

The following formcalculates the angular velocity of a motor based on the Hall
effect sensor signal and vice versa. See below for more details about the online
calculator.

## Signals

The folloging figure illustrates the signal of the Hall effect sensors (H1, H2 and H3).
The combination of the three sensors is also illustrated. This last one (F2 or T2) allows
high rate angular velocity measurement since it is three times faster than a single
Hall effect sensor.

## Formulas

The following formulas are used in the previous form. This one describes how
the frequency F1 (or period T1) can be calculated:

$$ F1_{Hz} = N_{rps} \times N_{poles} $$

The following describes how the frequency F2 (or period T2) can be calculated:

$$ F2_{Hz} = 2 \times N_{rps} \times N_{poles} \times N_{phases} $$

## See also

Last update : 06/26/2018