Allen-Bradley ControlNet Compact GuardLogix 1769, Руководство пользователя, Страница: 14 / 100

Chapter 1 ControlNet Overview
Table 3 - Bridges from an EtherNet/IP Network
Destination
Network
Modules for a 1768
CompactLogix System
Modules for a 1769
CompactLogix System
Modules for a
ControlLogix Chassis
Modules for a 1769
CompactLogix Packaged
Controller System
ControlNet
• 1768-L43 or 1768-L45
controller
• 1768-ENBT module
• 1768-CNB(R) module
Not applicable
• 1756-CN2 module
•
1756-CN2R module
• 1756-CNB module
•
1756-CNBR module
• 1756-ENBT module
•
1756-EN2T module
• 1756-EN2TR module
• 1756-EN3TR module
Not applicable
DeviceNet
• 1768-L43 or 1768-L45
controller
• 1768-ENBT module
• 1769-SDN scanner
• 1769-L32E or 1769-L35E
controller
• 1769-SDN scanner or 1788-
EN2DN module
(1)
• 1756-DNB module
• 1756-ENBT module
• 1756-EN2T module
• 1756-EN2TR module
• 1756-EN3TR module
• 1769-L23E-QB1B controller
• 1769-L23E-QBFC1B controller
• 1769-L23-QBFC1B controller
• 1769-SDN scanner
(1) Can serve as a dedicated standalone bridge from an EtherNet/IP network to a DeviceNet network.
Exchange Information on a
ControlNet Network
ControlNet communication modules use a message-based protocol that
implements a relative path to send a message from the producing module in a
system to the consuming modules. This protocol also lets you communicate
between devices on a ControlNet, DeviceNet, or EtherNet/IP network without
writing additional application code.
With unscheduled data, the device from which a message originates, such as a
Logix5000 controller, contains the path information that makes sure the message
reaches its consumers.
For a full explanation of unscheduled and scheduled data, see Network Update
Time (NUT ) on page 16 .
Because the producing module holds this information, other modules along the
path simply pass the information along and do not need to store it. The
significant benefits include the following:
•
You do not need to configure routing tables in the bridging module, which
greatly simplifies maintenance and module replacement.
•
You maintain full control over the route taken by each message, which
enables you to select alternative paths for the same end module.
Scheduled data in Logix-based systems use the producer/consumer networking
model instead of a source/destination (master/slave) model. The producer/
consumer model reduces network traffic and increases transmission speed.
14 Rockwell Automation Publication CNET- UM001E-EN-P - June 2016