IAI America ERC3 - Manual (Page 265)

Chapter 4 Operation
4.3
Operation in Pulse
Train Control Mode (How to Operate
Pulse
Train Control
Type)
255
„ Examples of electronic gear calculations:
When operating ERC3 with 3mm lead length ball screw in 0.01 (1/100) mm of the movement
per unit
(Encoder pulse of ERC3 = 800pulse/rev)
The electronic gear numerator (CNUM) is calculated as 8, while the electronic gear
denominator (CDEN) is calculated as 3. Based on these settings, the travel distance per
command pulse train input pulse becomes 0.01mm.
Caution:
Ɣ The fraction has to be completely reduced so both the electric gear numerator
(CNUM) and electric gear denominator (CDEN) can be 4096 or less and make them
to be integral numbers. (Do not stop reducing the fraction on the way.)
Ɣ CNUM and CDEN on the line axis have to satisfy the following relative formulas.
Ɣ Do not set the minimum movement unit out of the encoder resolution ability. If this
setting is conducted, the actuator would not start moving until enough command
pulse is stored in the encoder resolution error.
Ɣ Pay attention not to exceed the specification limit when setting the velocity,
acceleration and deceleration.
=No. of Encoder Pluses [pulse/rev]
Ball Screw Lead Length [mm/rev]
u Unit Travel Distance [deg/pulse]
=
800
3
u
1
100
=
8
3
Electronic Gear
Numerator (CNUM)
Electronic Gear
Denominator (CDEN)
2 31 t
Stroke Length [mm]
Ball Screw Lead Length [mm/rev]
u No. of Encoder Pluses [pulse] u CNUM
2 31 t
Stroke Length [mm]
Ball Screw Lead Length [mm/rev]
u No. of Encoder Pluses [pulse] u CDEM
Encoder resolution [mm/pulse] =
Ball Screw Lead Length [mm/rev]
No. of Encoder Pluses [pulse/rev]