Shihlin electric SDP Series, Manual

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communication or DI/DO, the overall pulse number calculation is as follows.
Total pulse number = r (number of revolutions) x 4 pulse number (0~4194303).
If the motor has rotated 10 cycles with 50000 pulse, the total pulse number is as follows
according to the above calculation:
The total pulse value = 10 x 50000
= 41993040 (pulse)
Method of reading motor absolute position
(1)Read the absolute position with communication.
Generally, you can use parameters which is in the status monitoring communication parameter
table in section 9.4 to read the data, and it is recommended to use the "Motor Feedback Pulse
Number (before E-Gear ratio)". The following is a brief table.
Communication
address
Item
Data
length
0x0000 Motor feedback pulse number(after E-Gear ratio) [pulse] 2word
0x0024 Motor feedback pulse number(before E-Gear ratio)
[pulse] 2word
(2)Read absolute position by PLC DIO communication
Return the position through the DI/DO handshake communication between the PLC and the
drive, you can refer to the descriptions in sections 13.1 and 13.2.
(3) Returning position by parameter setting
By setting parameter PA30 with communication, the encoder status and motor absolute position
are updated. If PA30 is set to 1, the drive does not clear the error when reading the position
value. If PA30 is set to 2, the drive clears the error at the same time when reading the position
value.
The servo motor moves slightly forward and backward to correct its position even it is stopped.
To avoid the difference between the reading motor position and actual positions, you can set
PA30 to have the motor’s actual position updated to the servo drive, and clears the position
error at the same time. After encoder status and motor absolute position are updated, PA30 is
automatically reset to 0. It means the controller can access the parameter values.
When the encoder status shows “absolute position lost” or “number of revolutions overflow”, it
means the reading absolute position is invalid. In this case, the coordinate initialization or
homing must be performed again.