Yaskawa MP930 - Manual (Page 233)

Absolute Position Detection
7.1.2 Structure of Absolute Position Detection
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7.1 Structure of the Absolute Position Detection Function
This section describes the Absolute Position Detection Function in the MP930.
7.1.1 Description of the Function
The Absolute Position Detection Function detects the position of the machine even if power
is turned OFF. This allows it to set the machine coordinate system automatically and to begin
operating automatically without having to return to the zero point after power is turned ON.
The following are features of the absolute position detection system.
D Eliminates the need to return to the zero point after power is turned ON.
D Enables the Stored Stroke Limit Function immediately after power is turned ON.
D Eliminates the need for a zero point dog and overtravel limit switch.
One of the following operating systems can be selected from parameter settings with this func-
tion.
D Incremental detection system using an incremental encoder.
D Absolute position detection system using an absolute encoder.
D Incremental position detection system using an absolute encoder.
7.1.2 Structure of Absolute Position Detection
J
Basic Terminology
The following explanation for basic terminology used in this chapter is provided to ensure ba-
sic understanding.
Absolute Encoder
Absolute position detection is generally performed in a semi-closed loop using an absolute en-
coder built into a Servomotor. The detector is comprised of an encoder that is used to detect
absolute position within one rotation and a counter that is used to count the number of rotations.
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