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Electronic Gear Ratio Calculation
Follow the Steps below:
1. Define the requirements of the positioning system
Establish the following:
Move distance per one revolution of load shaft.
Servo motor Encoder ppr (Pulse Per Revolution). (please refer to section 1-1-2 Servo Motor
Standards).
Motor / load Shaft deceleration ratio.
2. Move distance per one move command pulse.
Define the move distance caused by the transmission system as a result of, one move command
pulse from the host controller.
Ex: When 1 Pulse Command move = 1μm
If the Host Controller gives a move command of 2000 pulses, the transmission device will move by:
-
2mm1um/pulse2000pulse
(The Electronic Gear Ratio must be set correctly).
3. Calculate the Electronic Gear Ratio
Calculate the Electronic Gear Ratio according to the formula below:-
If the deceleration ratio between motor and load shaft is
m
n
(m = Motor Rotating number, n= Load Shaft Rotating Value), Then the formula for Electronic Gear Ratio is:
Warning!
The calculated Electronic Gear Ratio must be according to the conditions below, otherwise the
servo drive and motor will not function correctly.
020
020
1
eGearRatioElectronic
Encoder ppr ( Pulse Per Revolution) x 4 m
Electronic Gear Ratio = X
Move distance per load shaft revolution ÷ Move distance per command Pulse n
Encoder ppr ( Pulse Per Revolution) x 4
Electronic Gear Ratio =
Move distance per load shaft revolution ÷ Move distance per command Pulse