6
MG.60.N1.22
- VLT is a registered Danfoss trademark
VLT
®
5000 / VLT
®
6000
HVAC / VLT
®
8000 AQUA
LON
Concept
LonWorks
Overview
Applications
LonWorks is both an existing standard and
hardware developed by Echelon Corporation.
Echelon's stated goal is to establish a com-
modity solution to the presently daunting
problems of designing and building control
networks.
The result is LonMark Interoperability which
makes it possible for independent network
devices to operate together over a
LonWorks network. The LonMark program
was developed to address interoperability
issues. As a result, the LonMark
Interoperability Association Task Groups
(LonUsers Groups) were developed. The
task groups determine that each device on
the network has an object definition, create
The LonWorks communications structure is
similar to that of a local area network (LAN)
in that messages are continually exchanged
between a number of processors. A
LonWorks system is a determined local
operating network (LON). LON technology
offers a means for integrating various
distributed systems that perform sensing,
monitoring, control, and other automated
functions. A LON allows these intelligent
devices to communicate with one another
through an assortment of communications
media using a standard protocol.
LON technology supports distributed, peer-
to-peer communications. That is, individual
network devices can communicate directly
with one another without need for a central
control system. A LON is designed to move
sense and control messages which are
typically very short and which contain
commands and status information that
trigger actions. LON performance is viewed
in terms of transactions completed per
second and response time. Control systems
do not need vast amounts of data, but they
do demand that the messages they send
and receive are absolutely correct. The critical
factor in LON technology is the assurance
of correct signal transmission and verification.
An important LonWorks benefit is the
network’s ability to communicate across
different types of transmission media. The
N
EURON
chip is the heart of the LonWorks
system. The N
EURON
chip's commu-
nication port allows for the use of
transceivers for other media (such as coax
and fiber optic) to meet special needs.
LonWorks control devices are called nodes.
Physically, each node consists of a N
EURON
chip and a transceiver. With proper design,
the nodes become building blocks that can
be applied to control a variety of tasks, such
as lighting or ventilating, integrating a variety
of communications media.
The tasks which the nodes perform are
determined by how they have been
connected and configured. Because
hardware design, software design, and
network design may be independent in a
LonWorks-based system, a node’s function
can be programmed to accommodate the
networks in which it will be used.
standards and models to be used by
particular applications and create a common
platform for presenting data. A standard
network variable type (SNVT) facilitates
interoperability by providing a well defined
interface for communication between
devices made by different manufacturers.
The VLT Adjustable Frequency Drive
supports the node object and controller
standard object definitions of LonMark
Interoperability.
Customers are currently using LonWorks for
process control, building automation, motor
control, elevator operation, life safety
systems, power and HVAC distribution and
similar intelligent building applications.
