YASKAWA SVC - Σ-7-Series SERVOPACK Electronic Gear Ratio and MP3000 Settings

6.8 Precautions When Using Σ-7-series SERVOPACKs
6.8.2 Σ-7-series SERVOPACK Electronic Gear Ratio and MP3000 Settings
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Other Useful Functions
6.8.2 Σ-7-series SERVOPACK Electronic Gear Ratio and
MP3000 Settings
We recommend that you set the electronic gear ratio in the SERVOPACK to 1:1 when you use
the MP3000. However, if you use a Σ-7-series SERVOPACK that supports an encoder with 24-
bit resolution, the travel distances and deceleration times that you can specify will be restricted.
You can solve this problem by setting the electronic gear ratio in the Σ-7-series SERVOPACK to
16:1.
If the electronic gear ratio of the Σ-7-series SERVOPACK is set to 16:1, the motor will rotate
one rotation for 1,048,576 servo reference units (equivalent to 20 bits). To do this, set fixed
parameter No. 36 (Number of Pulses per Motor Rotation) to 1,048,576.
If greater resolution is required, set the electronic gear ratio of the Σ-7-series SERVOPACK to
1:1 and set fixed parameter No. 36 (Number of Pulses per Motor Rotation) to 16,777,216.
Σ-7 Electronic
Gear Ratio
Operation
16:1
(equivalent to
20 bits)
1:1
(24 bits)
If you set the electric gear ratio of a Σ-7-series SERVOPACK to 16:1, you will be able to use
an absolute encoder with an infinite-length setting only with the MP3000 with a version that
supports the Σ-7-series SERVOPACKs.
Reference unit selection = mm
Travel distance per machine rotation = 10,000 reference units
Motor gear ratio = 1
Machine gear ratio = 1
Number of pulses per motor rotation = 1,048,576
Pn20E = 16
Pn210 = 1
A 24-bit encoder is used.
MP3000 Σ -7
MECHATROLINK-III
Motor
If a movement of 10,000 reference
units is commanded, 1,048,576
pulses will be output.
The motor will rotate one rotation for a
reference of 1,048,576 servo reference
units.
Reference unit selection = mm
Travel distance per machine rotation = 10,000 reference units
Motor gear ratio = 1
Machine gear ratio = 1
Number of pulses per motor rotation = 16,777,216
Pn20E = 1
Pn210 = 1
A 24-bit encoder is used.
MP3000 Σ -7
MECHATROLINK-III
Motor
If a movement of 10,000 reference
units is commanded, 16,777,216
pulses will be output.
The motor will rotate one rotation for a
reference of 16,777,216 servo reference
units.
Information