Introduction; About This Manual; References - Danfoss VLT HVAC Drive Metasys N2 Manual

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VLT HVAC Drive Metasys N2

1.1.1. Introduction

The frequency converter control board is program selectable for use with the Johnson controls
Metasys N2 protocol. Metasys N2 is a master/slave control network. The physical layer is RS-485
compatible, half duplex 9600 baud shielded twisted pair. The N2 software protocol is designed to
be general in nature to accommodate the unique properties each device type may have. Every
device connection to the N2 network can be thought of as a small data manager. Data points in
the database are classified as analog I/O (floating point), binary I/O or integer data points - floats,
integers or bytes. Each data type has its own unique structure defined in the Metasys N2 system
Protocol Specification for Vendors.
The information in this manual is intended to provide you with comprehensive information on how
to install and set up the frequency converter for communication over a Metasys network.
For specific information on operation of the drive, refer to the
structions, MG.11.Ax.yy.

1.1.2. About this Manual

This manual is for both instructional and for reference purposes. This manual can also serve as a
guideline when you specify and optimize your communication system.
It is highly recommended that you read this manual in its entirety before initiating any program-
ming. It is assumed that the user has full knowledge of the capabilities and limitation of the
controller node in addition to full knowledge of the frequency converter.

1.1.3. References

In addition to this manual, the following two manuals should be consulted:
Operating Instruction, MG.11.Ax.yy
cation for Vendors, Johnson Controls number 04-3402-22, rev A
Johnson Controls METASYS N2 System Protocol Specifi-
and
MG.11.G1.02 - VLT ® is a registered Danfoss trademark
1. Overview
VLT ® HVAC Drive Operating In-
VLT ® HVAC Drive
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