Rockwell Automation 20-750-PNET Profinet Single Port Option Module User Manual
Page 89
Rockwell Automation Publication 750COM-UM006A-EN-P - January 2013
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Glossary
Profinet Network
PROFINET is the open industrial Ethernet standard of PROFIBUS
International (PI) for automation. PROFINET uses TCP/IP and IT standards,
and is, in effect, real-time Ethernet. The Profinet network is designed for
industrial communications, where both I/O and acyclic messages can be
transmitted over the network to communicate with industrial automation
equipment. The number of devices that a Profinet network can support depends
on the class of network it is installed in. For example, a network with a Class C IP
address can have 254 nodes.
General information about Profinet standards and the Profinet specification are
maintained by PROFIBUS & PROFINET International (PI). See
Reference/Feedback
The Reference is used to send a setpoint (for example, speed, frequency, and
torque) to the drive. It consists of one 32-bit word of output to the option
module from the network.
Feedback is used to monitor the speed of the drive. It consists of one 32-bit word
of input from the option module to the network.
Scanner
A scanner is a separate module (of a multi-module controller) or a built-in
component (of a single-module controller) that provides communication with
option modules connected to a network. See also
SI (Serial Interface)
A next generation communication interface used by various Allen-Bradley drives,
such as PowerFlex 750-Series drives.
Status Indicators
LEDs that are used to report the status of the option module, network, and drive.
They are on the option module and can be viewed when the drive is powered and
its cover is removed.
Stop Action
When communication is disrupted (for example, a cable is disconnected), the
option module and drive can respond with a stop action. A stop action results in
the drive receiving zero as values for Logic Command, Reference, and Datalink
data. If the drive was running and using the Reference from the option module, it
will stay running but at zero Reference.
Subnet Mask
An extension to the IP addressing scheme that lets you use a single network ID
for multiple physical networks. A bit mask identifies the part of the address that
specifies the network and the part of the address that specifies the unique node
on the network. A ‘1’ in the subnet mask indicates the bit is used to specify the
network. A ‘0’ in the subnet mask indicates that the bit is used to specify the
node.
For example, a subnet mask on a network may appear as follows: 11111111
11111111 11111111 11000000 (255.255.255.192). This mask indicates that 26
bits are used to identify the network and 6 bits are used to identify devices on
each network. Instead of a single physical Class C network with 254 devices, this
subnet mask divides it into four networks with up to 62 devices each.