
B–63833EN/03
9. CONNECTION TO FANUC I/O Link
164
Calculate the maximum allowable length of the cable for the manual pulse
generator, with the method described below.
Manual pulse generators are supplied with 5 VDC power. The drop in
voltage due to cable resistance must not exceed 0.2V (on 0V and 5V lines
in total).
0.2y
0.1 R 2L
m
Where
0.1 : Power supply current for the manual
pulse generator = 0.1 A
R : Wire resistance per unit length [Ω/m]
m: Number of 0–V wires (= number of 5–V wires)
L : Cable length [m]
Therefore,
m
R
Lx
Example: When cable A66L–0001–0286 is used
This cable consists of three pairs of signal lines and six power wires
(20/0.18, 0.0394
Ω/m).
When these three cables are used for 0V and 5V lines, the cable length is:
3
0.0394
Lx
=76.75[m]
Thus, the length is 76.75 m. (Because of the applicable regulation of
FANUC, however, the length is limited to 50 m.)
For two units, the cable can be extended to 38.37 m.
For three units, it can be extended to 25.58 m.
If the cable A66L–0001–0284#10P is used,
the cable can be extended to 12.88 m for one unit,
6.44 m for two units, and
4.29 m for three units.
Make sure that the following conditions are satisfied when manual pulse
generators other than those made by FANUC are used.
The relations between the HAn and HBn signals and the pulses issued to
the CNC are as shown in the figure below. The period of the pulses T
1
must be 200 µsec or greater and T
1
/4 must be 50 µsec or greater.
HAn
HBn
+ direction pulse
– direction pulse
Reverse direction rotation
Direction reverse
Click
point
T
1
4
T
1
4
T
1
4
T
1
T
1
Forward direction rotation