IDTECK Star FINGER006, User Manual

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7.2.3 Grounding System for Communication Cable
We recommend using proper grounding system on the communication cable. The best
method for grounding system is to put the shield wire of the communication cable to the 1
st
class earth grounding; however it is not so easy to bring the earth ground to the
communication cable and also the installation cost is raised.
There will be three grounding points where you can find during installation;
1) Earth Ground
2) Chassis Ground
3) Power Ground
The most important point for grounding system is not to connect both ends of shield wires
to the grounding system; in this case there will be a current flow through the shield wire
when the voltage level of both ends of shield wire is not equal and this current flow will
create noise and interfere to communications.
For the good grounding, we recommend to connecting ONLY one end of shield wire of
communication cable to the grounding system; If you find earth ground nearby, then
connect one end of shield wire to earth ground; If you do not have earth ground nearby,
then find chassis ground and connect one end of shield wire to chassis ground; If you do
not find both earth ground and chassis ground, then connect one end of shield wire to
power ground. (GND of FINGER006)
Note that if the chassis ground is not properly connected to the earth and floated from the
ground level, then grounding to the chassis ground will give the worst communication; in
this case we recommend to using power ground instead of chassis ground.
Figure: Grounding System