YASKAWA SGD7S-xxxDA0 series, Product Manual

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11.3 Parameter and Object Settings for Fully-closed Loop Control
11.3.5 External Absolute Encoder Data Reception Sequence
11-8
Related Parameters
Note: The maximum setting for the encoder output resolution is 4,096.
If the resolution of the external encoder exceeds 4,096, pulse output will no longer be possible at the resolu-
tion given in

Feedback Resolution of Linear Encoder on page 6-44.
11.3.5 External Absolute Encoder Data Reception Sequence
Refer to the following section for details.
7.9.4 Reading the Position Data from the Absolute Linear Encoder on page 7-42
With fully-closed loop control, the same sequence as for a Linear Servomotor is used.
11.3.6 Setting Unit Systems
Refer to the following section for details.
6.14 Setting Unit Systems on page 6-42
With fully-closed loop control, the same setting as for a Linear Servomotor is used.
11.3.7 Alarm Detection Settings
This section describes the alarm detection settings (Pn51B and Pn52A).
Pn51B (Excessive Error Level between Servomotor and
Load Positions)
This setting is used to detect the difference between the feedback position of the motor
encoder and the feedback load position of the external encoder for fully-closed loop control.
If the detected difference exceeds the setting, an A.d10 alarm (Motor-Load Position Error Over-
flow) will be output.
Note: If you set this parameter to 0, A.d10 alarms will not be output and the machine may be damaged.
Pn52A (Multiplier per One Fully-closed Rotation)
Set the coefficient of the deviation between the motor and the external encoder per motor rota-
tion.
This setting can be used to prevent the motor from running out of control due to damage to the
external encoder or to detect belt slippage.

Setting Example
Increase the value if the belt slips or is twisted excessively.
If this parameter is set to 0, the external encoder value will be read as it is.
If you use the default setting of 20, the second rotation will start with the deviation for the first
motor rotation multiplied by 0.8.
Pn281
(2281h)
Encoder Output Resolution
Setting Range Setting Unit Default Setting When Enabled Classification
1 to 4,096 1 edge/pitch 20 After restart Setup
Position
Pn51B
(251Bh)
Excessive Error Level between Servomotor and Load Positions
Setting Range Setting Unit Default Setting When Enabled
Classifica-
tion
0 to
1,073,741,823
1 reference unit 1000 Immediately Setup
Position