Yaskawa MP920 Motion Module - Manual (Page 52)

2 Motion Control
2.3.1 Prerequisites for Position Control
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2.3 Position Control
This section describes the prerequisites for position control, and position control without using
motion commands.
2.3.1 Prerequisites for Position Control
With position control, the axis is moved to the target position, stops there, and holds that
position (servo clamp).
An incremental encoder or a Yaskawa absolute encoder is used as the position detector.
When a Yaskawa absolute encoder is used, the absolute position is stored, even when the
power for the machine (positioning device) is disconnected. Therefore, when the power is
turned ON again, the zero point return operation is not required.
There are two position control methods. One method uses motion commands (OW††20),
and the other method does not use motion commands.
Whether or not motion commands (OW††20) are to be used is set in the motion parame-
ters shown in the following table.
Note: When bit 7 (motion command code selection) of motion fixed param-
eter No. 14 (Additional Function Selections) is not selected for use
and bit 8 (motion command code enable/disable) of RUN Mode Set-
tings (OW††00) motion setting parameter is set to “1” (= enabled),
the axis is controlled without motion commands (OW††20).
The position control mode is available with all Motion Modules. However, it can be used for the SVB-
01 and PO-01 Modules only when motion command code is enabled.
The following table shows position control mode availability for each Motion Module.
Motion Parameter Motion Command
(OW††20) Not
Used
Motion Command
(OW††20) Used
Motion fixed parameter No. 14
Bit 7 of Additional Function Selections
(Motion Command Code Selection) 0 (= Not used) 1 (= Used)
Motion setting parameter
Bit 8 of RUN Mode Settings (OW††00)
(Motion Command Code Enable/Disable) 0 (= Disabled) 1 (= Enabled)
Motion
Module
Position Control Mode
Motion Command Code
Enabled
Motion Command Code
Disabled
SVA-01A Available Available
SVA-02A Available Available
SVB-01 Available Not available
PO-01 Available Not available
IMPORTANT