
B–63323EN/03
6. CONNECTION OF I/O UNITS TO
MACHINE INTERFACE
249
0.2w
0.1 R 2L
m
Because
0.1 : MPG power supply current 0.1A
R : Resistance per wire length (Ω/m)
m : Wire Number(Both 0V and 5V)
L : Cable length(m)
Lv
m
R
Example: In case of cable A66L–0001–0286
It has 3 pairs signal wires and 6 power line wires
(20/0.18, 0.0394Ω/m).
If the cable is used and each 3 wires are used for 0V and 5V power line,
then
max. cable length is as follows.
Lv =
3
0.0394
76.75(m)
The answer is 76.75m, if MPG unit is 1.
(But FANUC decide any cable must be less than 50m.)
The answer is 38.37m, if MPG units are 2.
The answer is 25.58m, if MPG units are 3.
And In case of cable A66L–0001–0284#10P
The answer is 12.88m, if MPG units are 1.
The answer is 6.44m, if MPG units are 2.
The answer is 4.29m, if MPG units are 3.
If the customer will use a some other vender’s MPG ,not FANUC’s MPG,
the electrical condition must be as follows.
HAn, HBn signals form MPG and CNC internal pulse are as follows. A
cycle of the HA/HB pulse T
1
must be more than 200µsec and T
1
/4 must
be more than 50µsec.
HAn
HBn
T
1
4
T
1
4
T
1
4
T
1
T
1
Click
point
Reverse wheel
Normal wheel
Reverse wheel
in the direction of +
in the direction of –