Yaskawa MP940 Reference Manual - Manual (Page 310)

Absolute Encoder Usage Method MotionSuite™ MP940 Machine Controller Reference Manual
7-16
Absolute Encoder Usage Method
This section explains various cautionary items in absolute encoder usage, as well as
the zero-point setting method. The usage of the absolute encoder differs for linear axes
and rotary axes.
When Used with Linear Axes
Overview
The absolute encoder records the rotation from encoder zero-point into the
internal battery backup memory. Therefore, the coordinate system zero-point
may be obtained without executing a zero-point return operation after system
start. After system startup, the device operates in exactly the same manner as
an incremental encoder.
Because the rotations from the encoder zero-point can only be managed
within a range of -32768 ~ +32768 rotations, the rotations can be reset to "0"
when -32768~+32768 rotations are exceeded. The positions managed by the
MP940 before and after power ON differ if the system power is cycled in this
state.
A linear axis is an axis which has a range of motion using the absolute
encoder range of -32768 ~ +32767.
• Do not modify Zero-point Position Offset (OIxx06) while the machine is running in a linear axis.
This may result in damage to the machine or injury to personnel.
CAUTION
Reverse Limit Forward Limit
Zero
Point
Reverse Forward
0
(-32768)
Rotations
(+32767)
Rotations