Installation guide

Glossary
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N.C. contact normally closed contact. A relay contact pair that is closed when the relay coil is de-
energized and open when the coil is energized.
N.O. contact normally open. contact. A relay contact pair that is open when the relay coil is de-
energized and closed when the coil is energized.
NEMA National Electrical Manufacturers Association.
network cycle
time
The time that a master requires to complete a single scan of all of the configured I/
O modules on a network device; typically expressed in microseconds.
NIM network interface module. This module is the interface between an island bus and
the fieldbus network of which the island is a part. The network interface module’s
built-in power supply provides 5 V logic power to the Advantys STB I/O modules as
well as 24 V source power, as needed, to the support I/O modules. The NIM also
has an RS-232 interface that is the connection point for the Advantys configuration
software.
NMT network management. NMT protocols provide services for network initialization,
error control, and device status control.
object dictionary Sometimes called the "object directory," this part of the CANopen device model is a
map to the internal structure of CANopen devices (according to CANopen profile
DS-401). A given device’s object dictionary is a lookup table that describes the data
types, communications objects, and application objects the device uses. By
accessing a particular device’s object dictionary structure through the CANopen
fieldbus, you can predict its network behavior and, therefore, build a distributed
application that implements it.
open industrial
communication
network
A distributed communication network for industrial environments based on open
standards (EN 50235, EN50254, and EN50170, and others) that allows the
exchange of data between devices from different manufacturers.
output filtering The amount that it takes an output channel to send change-of-state information to
an actuator after the output module has received updated data from the NIM.
N
O