Glossary – Rockwell Automation 1440-RMA00-04RC XM-440 Master Relay Module User Manual
Page 89
89
Rockwell Automation Publication GMSI10-UM009D-EN-P - June 2011
Glossary
alarm
An alarm alerts you to a change in a measurement. For example, an alarm can
notify you when the measured vibration level for a machine exceeds a
pre-defined value.
alarm list
An alarm list is a set of alarms (from XM measurement modules) that will be
monitored by a relay in the XM-440 Master Relay module. Each XM-440 relay
has its own alarm list.
Automatic Device Replacement (ADR)
A means for replacing a malfunctioning device with a new unit, and having the
device configuration data set automatically. The ADR scanner uploads and
stores a device’s configuration. Upon replacing a malfunctioning device with a
new unit (MAC ID 63), the ADR scanner automatically downloads the
configuration data and sets the MAC ID (node address).
baud rate
The baud rate is the speed at which data is transferred on the DeviceNet
network. The available data rates depend on the type of cable and total cable
length used on the network:
The XM measurement modules’ baud rate is automatically set by the bus
master. You must set the XM-440 Relay module baud rate. You set the
XM-440 Master Relay to 125kb, 250kb, 500kb, or Autobaud if another device
on the network has set the baud rate.
bus off
A bus off condition occurs when an abnormal rate of errors is detected on the
Control Area Network (CAN) bus in a device. The bus-off device cannot
receive or transmit messages on the network. This condition is often caused by
corruption of the network data signals due to noise or baud rate mismatch.
Maximum Cable Length
Cable 125K
250K
500K
Thick Trunk Line
500m (1,640ft.)
250m (820ft.)
100m (328ft.)
Thin Trunk Line
100m (328ft.)
100m (328ft.)
100m (328ft.)
Maximum Drop Length
6m (20ft.)
6m (20ft.)
6m (20ft.)
Cumulative Drop Length
156m (512ft.)
78m (256ft.)
39m (128ft.)