Setting For The Encoder Divided Pulse Output - YASKAWA SGD7S Product Manual

Encoder Divided Pulse Output When Using a Linear
Servomotor
If you will use a Linear Servomotor, set the encoder output resolution (Pn281).
Encoder Output Resolution
Pn281 Setting Range
1 to 4,096
Note: The maximum setting for the encoder output resolution is 4,096. Pulse output at a linear encoder resolution
of 4,096 or higher is not possible.
Set the encoder output resolution for the encoder pulse output signals (PAO, /PAO, PBO, and
/PBO) from the SERVOPACK to the host controller.
The number of feedback pulses per linear encoder pitch is divided by the setting of Pn281
(after multiplication by 4) inside the SERVOPACK and then the resulting number of pulses is
output. Set the parameter according to the system specifications of the machine or host con-
troller.
The setting range depends on the Servomotor's maximum speed (Pn385) and the Linear
Encoder Scale Pitch (Pn282).
following formula.
Linear Encoder Pitch*/100
Upper limit of Pn281 =
*
The value depends on whether a Serial Converter Unit is used.
Using a Serial Converter Unit
Not Using a Serial Converter Unit (when the lin-
ear encoder and SERVOPACK are connected
directly or when a linear encoder that does not
require a Serial Converter Unit is used)
When the linear encoder pitch is 4 μm, the maximum motor speed is limited to 1 mm/s
Information
because of the maximum response frequency of the Serial Converter Unit.
If the setting is out of range or does not satisfy the setting conditions, an A.041 alarm
(Encoder Output Pulse Setting Error) will be output. If the motor speed exceeds the upper
limit for the set encoder output resolution, an A.511 alarm (Encoder Output Pulse Overspeed)
will be output.
The upper limit of the encoder output resolution is restricted by the dividing specifications of
the Serial Converter Unit.
Setting Example
Example
Correct setting for a linear encoder pitch of 20 μm and a maximum motor speed of 5 m/s
(Pn385 = 50): Pn281 = 28 (edges/pitch)
Incorrect setting: Pn281 = 29 (edges/pitch) (An A.041 alarm would be output.)
Pulse Output Example
Example
When Pn281 = 20 (20-edge output (5-pulse output) per linear encoder pitch)
Phase A
Phase B
Setting Unit Default Setting
1 edge/pitch
*
You can calculate the upper limit of the setting of Pn281 with the
72
Pn385
Setting of Pn282
The linear encoder pitch is automatically detected by the SERVO-
PACK, so the setting of Pn282 is ignored. You can use the monitor
functions of the SigmaWin+ to check the linear encoder pitch that
was automatically detected.
Linear encoder pitch
6.5 Encoder Divided Pulse Output

6.5.2 Setting for the Encoder Divided Pulse Output

Speed
When Enabled
20 After restart
Position Force
Classification
Setup
6-25
6