Yaskawa FSP Amplifier - Manual (Page 92)

FSP Amplifier User’s Manual Chapter 5: Parameter Settings and Functions
5-25
5.2.5. Using the Electronic Gear Function
The electronic gear function enables the servomotor travel distance per
input reference pulse to be set to any value. It allows the pulses generated
by the host controller to be used for control without having to consider the
equipment gear ratio or the number of encoder pulses.
When the electronic gear
function is not used
When the electronic gear
function is used
Payload Payload
Ball screw pitch: 6 mm (0.24 in) No. of encoder pulses: 2048
To move a payload 10 mm (0.39 in):
1 revolution is 6 mm. Therefore,
10 ÷ 6 = 1.6666 revolutions
2048 x 4 pulses is 1 revolution.
Therefore,1.6666 x 2048 x 4 = 13653
pulses are input as reference.
The equation must be calculated at the
host controller.
Equipment conditions and reference
units must be defined for the electronic
gear function beforehand.
To move a payload 10 mm (0.39 in):
Reference unit is 1μm. Therefore,
10 mm
1 μm
= 10000 pulses
„ Setting the Electronic Gear (for Reference Pulses)
Calculate the electronic gear ratio (B/A) using the following procedure, and
set the values in parameters Pn202 and Pn203.
1. Check equipment specifications related to the electronic gear:
• Deceleration ratio
• Ball screw pitch
• Pulley diameter
Ball screw pitch
Deceleration ratio
Encoder Type
Number of Encoder Pulses
Per Revolution (PPR)
13-bit 2048
16-bit 16384
Incremental encoder
17-bit 32768
16-bit 16384
Absolute encoder
17-bit 32768
Note: The number of bits representing the resolution of the applicable encoder is not the same as the number of
encoder signal pulses (A and B phase) output from the servo amplifier.