Allen-Bradley controllogix 1756-L55M12, User Manual

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Publication 1756-UM001G-EN-P - January 2007
30 Communicate over Networks
Connections over DeviceNet
The ControlLogix controller requires two connections for each
1756-DNB module. One connection is for module status and
configuration. The other connection is a rack-optimized connection
for the device data.
The 1756-DNB module has fixed sections of memory for the input and
output data of the DeviceNet devices on the network. Each device on
your network requires either some input or output memory of the
scanner. Some devices both send and receive data, so they need both
input and output memory. The 1756-DNB module supports up to:
•
124 DINTs of input data.
•
123 DINTs of output data.
Additional Resources
For more information, consult these publications:
•
DeviceNet Modules in Logix5000 Control Systems User Manual,
publication DNET-UM004
•
Logix5000 Controllers Design Considerations Reference Manual,
publication 1756-RM094