LINK Systems LinkNet II - Manual (Page 11)

Section 2 Installation
LinkNet is connected to each piece of equipment in a bussed arrangement commonly called “daisy
chaining”. The means that the communications cable goes from the computer to the first machine, from
the first machine to the second, from the second to the third, and so on as shown in Figure 2.1.
The “Drop Boxes” shown in the figure are small boxes that contain plugable terminal strips. The
boxes mount on the press and serve as junctions for the network wire to come in to the machine, go out
to the next machine, and drop to Link equipment. In addition, the boxes can contain circuitry (called a
repeater) to enable the network to work with extremely long cable lengths or with more than 32
machines. At the computer, an RS232 to RS485 converter is necessary. This converts the standard
serial port on the host computer to a differential serial port suitable for electrically noisy industrial
environments. Link makes an RS232 to RS485 converter specifically for this purpose with termination
resistors built in that provide for reliable communications.
The computer that runs the network should be capable of running Windows 98, Windows ME,
Windows NT 4.0 (service pack 4 or higher), or Windows 2000.
Windows 2000 is the preferred platform for LinkNet 2. LinkNet 2 will run on the
other Windows version mentioned above, but Windows 2000 has proven to be far
more stable!
The network wiring should be Belden 8103 or equivalent (three twisted pairs and a shield) and
should not exceed 4000 ft (unless using a repeater).
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Drop
Box In Out
Unit
Figure 2.1: LinkNet Wiring Overview
Manual Version 1.1 10/28/2001 2.1