
4.HARDWARE CONNECTIONS V. CONNECTION B-63644EN/02
- 318 -
NOTE
1 The ground between PC/HUB side and machine
system side must be separated. If it is impossible to
separate the ground because there is only one
grounding point, connect the ground cable for each
system to the grounding point independently. (Refer
Fig.1)
The resistance for grounding must be less than 100-
ohm (Class D). The thickness of the ground cable is
the same as the thickness of AC power cable or
more. At least thickness of 5.5mm
2
is necessary.
2 Note that the number of allowable hub-to-hub
connections depends on the type of hub.
3 There is possibility that noise makes the obstacle of
communication even if the ground is separated using
the 100BASE-TX. In the case of using the Fast
Ethernet board under the worst environment, please
separate between the PC/Trunk line side and
machine system side completely using the
100BASE-FX (Optical fiber media).
Ground wire on
machine s
stem
Note 2
Ground wire on machine
system
Ground point
FG
Ground wire on personal
computer/HUB
HUB
FG
Fig.4.5.3(c) Wiring on a Single Ground Point