
B-63943EN/02 8.CONNECTION TO FANUC I/O Link
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NOTE
Calculate the MPG cable max. Length as refer to the
following calculation.
MPG needs a 5VDC power supply and the voltage must be less than
0.2V dropping. (the 0.2V dropping includes the resistance in the
cable.)
0.1×R×2L
0.2≥
m
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)
Because
M
L≤
R
Example: In case of cable A66L-0001-0286
It has 3 pairs signal wires and 6 power line wires (20/0.18, 0.0394
Ω/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.
3
L≤
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 200 µsec and 4/T
1
must be more than 50 µsec.
HAn
HBn
in the direction of +
in the direction of -
Normal wheel Reverse wheel
Reverse wheel
Click point
T
1
4
T
1
4
T
1
4
T
1
T
1