Title: Hardware Installation Guide.pdf
The signal ground (SG) provides a common mode signal reference for the communicating devices. Each device must connect its SG to the cable shield drain wire. Failure to use the SG connection may cause communication errors. If the environment is known to be noisy, an additional wire may be used for the signal ground. The shield can then be grounded at one end only (to prevent ground loops) as a signal ground.1.5.3Device to Device ConnectionCommunication cables for RS-485 should be laid out in a daisy chain. Long stubs (T connection) should be avoided because they create discontinuities and degrade signals. DO NOT connect devices in STAR configuration unless using the LNL-8000 Star Multiplexer. STAR connection creates long stubs and causes difficulty in cable termination.1.5.4Cable Termination