The Precise pseudo absolute encoder has an embedded pattern that can uniquely determine the absolute position of an axis. To read this pattern, an axis only has to be moved a very short distance, typically just a few hundred encoder counts. The procedures for homing an axis equipped with this encoder are defined in the following table.
Method# |
Description |
Use |
---|---|---|
Method -5 | Moves axis in the positive direction and stops when a pattern is detected. If the upper hard stop is encountered, moves axis in the negative direction and stops when a pattern is detected. | These methods are normally employed on linear encoders or very high resolution rotary encoders where unique patterns exist along the entire length of the axis. |
Method -6 | Moves axis in the negative direction and stops when a pattern is detected. If the lower hard stop is encountered, moves axis in the positive direction and stops when a pattern is detected. | |
Method -7 | Moves axis in the positive direction until the upper hard stop is encountered. Then moves the axis in the negative direction and stops when the next pattern is detected. | These methods are normally employed on rotary encoders where patterns are unique within a single turn of the encoder but the encoder rotates several revolutions for the entire travel of the axis. |
Method -8 | Moves axis in the negative direction until the lower hard stop is encountered. Then moves the axis in the positive direction and stops when the next pattern is detected. |