OPTO 22 SNAP PAC R SERIES, Руководство пользователя

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CHAPTER 3: SYSTEM INFORMATION
SNAP PAC R-Series Controller User’s Guide 23
NOTE: Make sure you put 3 and 6 on the same pair, or you may experience noise and distance limitations. Also, make
sure to include all pairs, since they are required for 100 Mbps.
Attaching the Controller to an Existing Ethernet Network
The first rule in attaching SNAP PAC R-series controllers to an existing network is to work closely with your
system administrator, who must determine network topology and hardware. Be sure to consider the impact
on your existing network of adding the controllers.
In addition, make sure the system administrator understands that each controller must have a fixed (static) IP
address, whether or not a Dynamic Host Configuration Protocol (DHCP) server is used on the network. For
more information on IP addresses, see the
PAC Manager User’s Guide .
If you are using SNAP PAC R-series controllers for data acquisition, you can place the controller anywhere on
an existing Ethernet network. If you are using the controller with control applications, however, the network
segment design will depend on the number of hosts, the number of data transactions, and issues of data
security. With fewer hosts and fewer data transactions, data packet collisions are less likely and system
performance improves. If collisions are a problem, and especially if you need high throughput and predictable
response times, it’s best to put the controller on a separate switched network segment. We recommend
switches, not hubs. For best performance, use a 100 Mbps network.
Segmenting the Control Network
NOTE: This implementation requires PAC Project Professional. For more information, see the SNAP PAC R-series data
sheet (form 1594) and the SNAP PAC S-series data sheet, form 1584). You may also consider using a router, network
switch, or other gateway device.
If you need to segment the control system network from the main network backbone, you can use the two
Ethernet interfaces on either the SNAP PAC R-series or an S-series controller. One interface can be connected
to the enterprise network, and the other used for the control system. See the diagram on
page 27 .
NOTE: If you are using Wired+Wireless models, one of the segmented networks can be a wireless LAN.