Rockwell Automation 20-COMM-K CANopen Adapter - Manual (Page 113)

Glossary G-5
20-COMM-K CANopen Adapter User Manual
Publication 20COMM-UM012B-EN-P
Life Time Factor
See Life Guarding.
Logic Command/Logic Status
The Logic Command is used to control the PowerFlex 7-Class drive (for
example, start, stop, direction). It consists of one 16-bit word of output to
the adapter from the network. The definitions of the bits in this word depend
on the drive, and are shown in
Appendix D .
The Logic Status is used to monitor the PowerFlex 7-Class drive (for
example, operating state, motor direction). It consists of one 16-bit word of
input from the adapter to the network. The definitions of the bits in this
word depend on the drive, and are shown in
Appendix D .
M Master-Slave Hierarchy
An adapter configured for a master-slave hierarchy exchanges data with the
master device. Usually, a network has one controller which is the master
device, and all other devices (for example, drives connected to CANopen
adapters) are slave devices. On a network with multiple controllers (called a
multimaster hierarchy), each slave device must have a controller specified
as a master.
N NMT (Network Management)
The NMT master of a CANopen network can transmit NMT messages
which forces the nodes to change to another NMT state. The CANopen state
machine specifies these states as Initialization, Pre-Operational,
Operational, and Stopped.
Node Address
A CANopen network can have as many as 64 devices connected to it. Each
device on the network must have a unique node address between 0 and 63.
Node address 63 is the default used by uncommissioned devices. Node
addresses are sometimes called “MAC IDs.”
Node Guarding
Node Guarding is used for error control to check that any CANopen device
is working properly. The mechanism used for guarding is based on the
master/slave relationship. The NMT master guards all of its NMT slaves
cyclically (cycle time = Guard Time) by using an RTR frame. Any
CANopen slave responds to this RTR frame to guarantee that the
application program is running.
NVS (Non-Volatile Storage)
NVS is the permanent memory of a device. Devices such as the adapter and
drive store parameters and other information in NVS so that they are not lost
when the device loses power. NVS is sometimes called “EEPROM.”