DATA-LINC GROUP

Appendix B

Line Conditioning

LCM100 User’s Guide

In some industrial installations, power lines must be conditioned to prevent the FSK signal from being shunted by distributed capacitance possibly associated with other loads connected to the line. Motors and transformers, for example, may have very high distributed capacitance.

Adequate communication in such circumstances may require: 1) installation of signal couplers at the power distribution panel to provide a low impedance path between different hot lines; 2) isolation of noisy equipment or equipment that presents a low impedance to high frequency signals, such as some power line filters commonly used with computer equipment.

Signal Couplers

One signal coupler is sufficient for all cross-phase communications in a signal phase system. See Figure 4 below:

DTE

DCE

FSK

A Phase

 

 

 

 

 

 

 

Signal

 

LCM100-1

 

RS-232C

Coupler

 

 

 

 

 

 

 

 

 

 

 

 

B Phase

Signal

Coupler

C Phase

FSK

LCM100-2

RS-232C

 

 

Neutral

Figure 4: Signal Coupler in Three Phase Systems

PN 161-09998-001A

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Omron LCM100 manual Appendix B, Line Conditioning, Signal Couplers