Datasheet

IDUINO for Maker’s life
Rotary Encoder Basics
A rotary encoder has a fixed number of positions per revolution. These positions
are easily felt as small “clicks” you turn the encoder.This module has thirty of
these positions.
On one side of the switch there are three pins. They are normally referred to
as A, B and C.
In the case of the SE055, they are oriented as shown.
Inside the encoder there are two switches. Once switch connects pin A to pin C
and the other switch connects pin B to C.
In each encoder position, both switches are either opened or closed. Each
click causes these switches to change states as follows:
If both switches are closed,turning the encoder either clockwise or
counterclockwise one position will cause both switches to open
If both switches are open,turning the encoder either clockwise or
counterclockwise one position will cause both switches to close.
The illustration below is representative of how the switch is constructed.