SPX Cooling Technologies CS4000 manual Using a 485 Network using Sdlc

CS4000 Mini Controller with Ethernet

Using a 485 Network using SDLC

In a 485 network, the controller is linked to a LAN, via cable between the first controller’s RS-485 connector and the port for the Synchronous Data Link Control (SDLC) card installed on the host computer. Each controller in the 485 network is connected to the next in a daisy chain fashion. The computer is connected to the first controller, the first controller is connected to the second controller, and so on until the network terminates with the last controller. See Figure 1-2. In this mode of operation, you can have as many as 32 TCMs attached and running from a single supervising computer.

This type of network requires:

•Pentium class computer (500 MHz or above).

•Microsoft Windows NT, version 4.0 or above.

•At least 128 MB RAM.

•Installed SDLC card.

•Visual Supervisor installed on the computer in permanent mode.

•RS-485 cable and connector.

In this configuration, the computer permanently connected to the network runs Visual Supervisor which now takes on the role of supervising all of the controllers on the LAN for both data and parameter set information, as well as being the connection point for the LAN. To set up a 485 network, refer to Chapter 6. Setting Up the 485 Network.