YASKAWA Sigma-II Series, User Manual

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10.3 Additional Functions
10-7
10
Upgraded V
ersions
10.3.2 Improvement of Dividing Output Resolution
The upper limit of PG dividing pulse (Pn201) is 16384 [P/R] that is decided for 16-bit encoder. However, direct-
drive servomotors are equipped with 20-bit encoder as standard. Therefore, the parameter Pn212 is added to
adapt the dividing pulse setting for 20-bit encoder.
For the PG dividing pulse setting, either the existing Pn210 or the newly added Pn212 can be used.
Select Pn201 or Pn212 by the switch for parameters. The factory setting is Pn201.
• Dividing pulse is set in the resolution 16-bit or less, use Pn201.
• Dividing pulse is set in the resolution 17-bit or more, use Pn212.
For the setting method of dividing ratio for 17-bit or more resolution, refer to (2) Setting PG dividing ratio of 5-
digit or more on the next page.
(1) Related Parameters
Parameter Description
Pn207 n. † 0 †† Uses the parameter Pn201 (For 16-bit or less) as the dividing ratio (Factory setting).
n. † 1 †† Uses the parameter Pn212 (For 17-bit or more) as the dividing ratio.
Pn201
PG Dividing Ratio (For 16-bit or less)
Setting Range Setting Unit Factory Setting Setting Validation
16 to 16384 1 P/rev 16384 After restart
Pn212
PG Dividing Ratio (For 17-bit or more)
Setting Range Setting Unit Factory Setting Setting Validation
16 to 1073741824 1 P/rev 2048 After restart
The setting range of Pn212 differs depending on the encoder used.
The upper limit of dividing output frequency is 1.4 Mpps because of the restrictions on the hardware. Therefore, setting a
high number of pulses limits the motor speed.
The following table shows the setting conditions when Pn212 is used.
For settings higher than 16384 P/R, pulses must be set in the following increments.
The setting error alarm A.09 (dividing ratio setting error) will occur if the setting is outside the allowable range or does not
satisfy the setting conditions. The overspeed alarm A.51 will occur if the motor speed exceeds the upper limit.
When setting the pulse dividing ratio using a digital operator or panel operator, the display of the number of pulses incre-
ments as shown in the above table and the upper limit will not increment above the resolution of mounted encoder.
When Pn212 is set without connecting a servomotor to the SERVOPACK, the upper limit is automatically set to 2
30
(=1073741824: the maximum output value of the SERVOPACK) since the encoder resolution of the servomotor is
unknown.
Therefore, it is recommended to set Pn212 after connecting a servomotor.
Speed Position
Torque
Speed
Position
Torque
Encoder Resolution
(Bits)
Number of Encoder Pulses
per Revolution (P/R)
Setting Range (P/R)
13
16
17
20 2048
16384
32768
262144
16 to 2048
16 to 16384
16 to 32768
16 to 262144
Pn212 needs not
be used.
PG Dividing Ratio
Setting (P/R)
Increments
(P/R)
Motor Speed Upper Limit (min
-1
)
16 to 16384
16386 to 32768
32772 to 65536
65544 to 131072
131088 to 262144 1-pulse
2 -pulse
4 -pulse
8 -pulse
16 -pulse
No limit (up to the motor maximum speed)
82
×
10
6
/Set value