Samsung SSA-R2010/EXP manual EARTH-GROUNDING the Communication Cables, Host PC

installation and external connection

EARTH-GROUNDING THE COMMUNICATION CABLES

It is recommended to use a proper grounding system for the communication cables.

The best grounding method is to earth-ground the shield wire of the communication cable. However, the earth-grounding of the communication cable is not easy, and it also causes an increased installation cost. There are three grounding points available for installation:

1.Earth Ground

2.Chassis Ground

3.Power Ground

The most important thing about the earth-grounding does not lie in connecting either end of the shield wire to the grounding system; This will cause a current flow through the shield wire when the voltage level of both ends of the shield wire is not equal and this current flow will introduce some noise and interference to communications.

It is recommended to connect ONLY one end of the shield wire of the communication cable to the grounding system. If you can locate an earth-grounding point nearby, connect one end of the shield wire to that point.

If you could hardly locate an earth grounding point nearby, connect one end of the shield wire to the chassis ground point. If you could locate neither of an earth or chassis grounding point nearby, connect one end of the shield wire to the power ground point (GND).

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 yield the worst communication performance. If this is the case, use the power ground point rather than the chassis ground.

RS-485/RS-232

RS-232 ConverterCommunication

Wires

Connect ShieldWire Open

HOST PC

Earth Ground

or Chasis Ground or Power Ground

	RS-485	RS-485	RS-485
GND	GND	GND	GND

12_ installation and external connection