ABB ACS320 series, User Manual

Page: 302 / 442

302 Fieldbus control
N2 protocol technical data
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Overview
The N2 fieldbus connection to the ACS320 drives is based on an industry standard
RS-485 physical interface. The N2 fieldbus protocol is a master-slave type, serial
communication protocol, used by the Johnson Controls Metasys® system. In the
Metasys architecture the N2 fieldbus connects object interfaces and remote
controllers to Network Control Units (NCUs).
The N2 fieldbus can also be used to connect ACS320 drives to the Metasys
Companion product line.
This section describes the use of the N2 fieldbus with the ACS320 drives’ connection
and does not describe the protocol in detail.
Supported features
In the N2 fieldbus protocol the ACS320 drive appears as a “virtual object”.
A virtual object is made up of:
• Analog Inputs
• Binary Inputs
• Analog Outputs
• Binary Outputs
• Internal values for Floating point, Integer, and Byte values.
The ACS320 drive does not support N2 fieldbus communication “internal values”.
All of the Analog and Binary I/O objects are listed below, starting with N2 analog input
objects below.
ACS320
Analog Inputs
Binary Inputs
Internal values, Float, Integer, Byte
Analog Outputs
Binary Outputs
Virtual Object
Metasys
Note: Metasys inputs are drive outputs and
drive inputs are Metasys outputs