TECO JSDG2S-75B-E - Page 278

5-153
When the external encoder or optical ruler is used to control full-closed loop, it is necessary to set
Pn348 (resolution corresponded to one cycle of full-closed loop Encoder) first. The following is an
example when using the screw with optical ruler:
Pn348
󰇛
ResolutioncorrespondedtoonecycleoffullclosedloopEncoder
󰇜

ScrewPitch
Resolution

1m
0.1um
 10000󰇛pulse󰇜  2500󰇛ppr󰇜
After setting full-closed Encoder resolution, the user can set operation direction along with
Pn349 (full-closed operation direction setting) or with Pn347 (full-closed loop maximum error) to set
the maximum range of actual and external encoder and use Un-52 (error between external and motor
encoder) to monitor the error between these two systems. When exceeds the range, AL.022 alarm
signal will occur (excessive pulse error between motor and load) and the servo stops operation. Lastly,
set Pn346 (full-closed loop function diving selection) according to the requirement.
Push manually (no excitation); calculate the total move distance of motor count according to Un-14
(motor feedback-pulse number in one rotation) and Un-16 (motor feedback-rotation number).
Compare the total position of this motor with Un50 (external encoder pulse number) to check if the
directions are the same? Is the proportion of both values close to motor resolution and Pn348?
If the platform is like what shown in Fig. 1, ignore the effect of backlash. From status display
parameter, the user will know Un-50 (external encoder pulse number) is 2500, and Un14 is 32768.
The value of Pn348 (resolution corresponded by full-closed loop encoder one cycle) can be calculated
accordingly:
Pn348
󰇛
Externalencoderresolution
󰇜

1
4
Un50
131072
󰇛
Motorencoderresolution
󰇜
Un14

1
4
2500
131072
Un14
 2500ppr