Rockwell Automation 20-750-DNET PowerFlex DeviceNet Option Module User Manual
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Rockwell Automation Publication 750COM-UM002B-EN-P - October 2012
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Glossary
Option Module
Devices such as drives, controllers, and computers usually require a network
communication option module to provide a communication interface between
them and a network such as DeviceNet. An option module reads data on the
network and transmits it to the connected device. It also reads data in the device
and transmits it to the network.
The 20-750-DNET DeviceNet option module connects PowerFlex 750-Series
drives to a DeviceNet network. Option modules are sometimes also called
‘adapters’, ‘cards’, ‘embedded communication options’, and ‘peripherals’. On
PowerFlex 750-Series drives, option modules can also be I/O modules, encoder
modules, safety modules, and so forth.
PCCC (Programmable Controller
Communications Command)
PCCC is the protocol used by some controllers to communicate with devices on
a network. Some software products (for example, DriveExplorer and
DriveExecutive software) also use PCCC to communicate.
Ping
A message that is sent by a DPI product to its peripheral devices. They use the
ping to gather data about the product, including whether it can receive messages
and whether they can log in for control.
Polled I/O Data Exchange
A device that is configured for polling I/O data exchange sends data immediately
after it receives a request for the data. For example, an option module receives a
Logic Command from the scanner and then sends back the Logic Status of the
connected PowerFlex drive.
PowerFlex 750-Series (Architecture
Class) Drives
Allen-Bradley PowerFlex 750-Series drives are part of the PowerFlex 7-Class
family of drives.
Producer/Consumer Network
On producer/consumer networks, packets are identified by content rather than
an explicit destination. If a node needs the packet, it will accept the identifier and
consume the packet. Therefore, the source sends a packet once and all the nodes
consume the same packet if they need it. Data is produced once, regardless of the
number of consumers. Also, better synchronization than Master-Slave networks
is possible because data arrives at each node at the same time.
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.
RSLogix 5000 Software
RSLogix 5000 software is a tool for configuring and monitoring controllers to
communicate with connected devices. It is a 32-bit application that runs on
various Windows operating systems. Information about RSLogix software can be
found at
. See also Studio 5000
environment.