ABB ACS 400 User manual

User’s Guide
N2 Protocol
ACS/ACH 400 AC Drives
A
BB Drives

Direct N2 Bus Interface
For ACS/ACH 400 AC Drives
User’s Guide
ACH400-N2-US-04
3AUA489002B5856 R0101 Rev B
Effective: 11/1/01
Supersedes: 6/30/00
Copyright © 2001 ABB Inc. All Rights Reserved.
3AUA489002

ACS/ACH 400 Direct N2 Bus Interface iii
Safety Instructions
Overview This chapter states the safety instructions that
must be followed when installing into a network
and operating the direct N2 Bus interface.
The material in this chapter must be studied
before attempting any work on, or with, the unit.
Warnings and Notes This manual incorporates two types of safety
instructions. Warnings are used to inform of
conditions which can, if proper steps are not
taken, lead to a serious fault condition, physical
injury and death. Notes are used when the
reader is required to pay special attention or
when there is additional information available
on the subject. Notes are less crucial than
Warnings, but should not be disregarded.
Warnings Readers are informed of situations that can
result in serious physical injury and/or serious
damage to equipment with the following
symbols:
Dangerous Voltage Warning: warns of
situations in which a high voltage can cause
physical injury and/or damage equipment. The
text next to this symbol describes ways to
avoid the danger.
General Warning: warns of situations which
can cause physical injury and/or damage
equipment by means other than electrical. The
text next to this symbol describes ways to
avoid the danger.
Electrostatic Discharge Warning: warns of
situations in which an electrostatic discharge
can damage equipment. The text next to this
symbol describes ways to avoid the danger.

Safety Instructions
iv ACS/ACH 400 Direct N2 Bus Interface
Notes Readers are notified of the need for special
attention or additional information available on
the subject with the following symbols:
General Safety
Instructions WARNING! All electrical installation and
maintenance work on the drive should be
carried out by qualified electricians.
The drive and adjoining equipment must be
properly grounded.
Do not attempt any work on a powered drive.
After switching off the main power, always
allow the intermediate circuit capacitors 5
minutes to discharge before working on the
frequency converter, the motor or the motor
cable. It is good practice to check (with a
voltage indicating instrument) that the drive is
discharged before beginning work.
The motor cable terminals of the drive are at a
dangerously high voltage when main power is
applied, regardless of motor operation.
There can be dangerous voltages inside the
drive from external control circuits even when
the drive’s main power is shut off. Exercise
appropriate care when working with the unit.
Neglecting these instructions can cause
physical injury and death.
WARNING! There are several automatic
reset functions in the drive. If selected, they
reset the unit and resume operation after a
fault. These functions should not be selected
if other equipment is not compatible with this
kind of operation, or if such action can create
a dangerous situation.
CAUTION! Caution aims to draw special attention to a
particular issue.
Note: Note gives additional information orpoints out
more information available on the subject.

Safety Instructions
ACS/ACH 400 Direct N2 Bus Interface v
More Warnings and Notes are printed
throughout this manual where applicable.

Safety Instructions
vi ACS/ACH 400 Direct N2 Bus Interface

ACS/ACH 400 Direct N2 Bus Interface vii
Table of Contents
Safety Instructions
Overview.............................................................................iii
Warnings and Notes ...........................................................iii
Warnings........................................................................iii
Notes............................................................................. iv
General Safety Instructions................................................ iv
Chapter 1 – Introduction
How To Use This Manual.................................................1-1
Intended Audience...........................................................1-2
Conventions Used In This Manual...................................1-2
Analog Inputs ..............................................................1-2
Analog Outputs............................................................1-2
Binary Inputs ...............................................................1-2
Binary Outputs.............................................................1-3
Change of State (COS)...............................................1-3
N1LAN.........................................................................1-3
N2Bus..........................................................................1-3
On-Line / Off-Line........................................................1-3
Terminal Block.............................................................1-4
Related Publications........................................................1-4
Chapter 2 – Overview of the N2 Connection
Introduction......................................................................2-1
Metasys Integration..........................................................2-2
Device Type.....................................................................2-3
DDL File......................................................................2-4

viii ACS/ACH 400 Direct N2 Bus Interface
Chapter 3 – Installation
Introduction......................................................................3-1
Controlling the drive....................................................3-1
Feedback from the drive.............................................3-2
Hardware Installation.......................................................3-2
Wiring..........................................................................3-2
Connections................................................................3-2
Grounding and Termination........................................3-3
Chapter 4 – Programming
Programming of the Drive................................................4-1
Supported Features.........................................................4-1
Analog Input................................................................4-2
Binary Input.................................................................4-2
Analog Output.............................................................4-2
Binary Output..............................................................4-3
Communication Setup.....................................................4-3
Output Point Configuration ..............................................4-6
Analog Outputs...........................................................4-6
Binary Outputs............................................................4-7
Fault Queue.....................................................................4-8
Faults..........................................................................4-8
Chapter 5 – Fault Tracing
Fault Diagnostics.............................................................5-1
Normal operation ........................................................5-1
No Metasys station on line..........................................5-2
Duplicate station .........................................................5-2
Swapped wires............................................................5-2
Oem Application Fault.................................................5-2
Intermittent off-line occurrences..................................5-3
Metasys Commissioning.............................................5-3
Summary .........................................................................5-3
Appendix A – I/O Point List
Parameters......................................................................A-1
Appendix B – DDL File for NCU
ACH_400.DDL.................................................................B-1

ACS/ACH 400 Direct N2 Bus Interface 1-1
Chapter 1 – Introduction
This chapter describes the purpose and
contents of this manual, describes the intended
audience, explains conventions used in this
manual, and lists related publications.
How To Use This
Manual The purpose of this manual is to provide you
with the information necessary to install, start-
up, and program an ACS/ACH 400 Adjustable
Frequency AC Drive for the direct Johnson
Controls N2 Bus connection. This manual also
gives recommendations for external
connections, wiring, routing, and cable sizes.
Chapter 1 - Introduction, the chapter you are
reading now, introduces you to the ACS/
ACH 400 N2 Bus Installation & Start-up Manual
and conventions used throughout the manual.
Chapter 2 - Overview of the N2 Bus connection
gives an overview of the direct N2 serial
communication implementation for the ACS/
ACH 400 drives. This chapter describes all the
different services provided by the network.
Chapter 3 - Installation describes planning for
the network installation. This chapter also
includes the requirements and connections for
the serial interface wiring.
Chapter 4 - Programming describes how to
program the ACS/ACH 400 drives for the N2
Bus. This chapter also lists all the new and
modified parameters, which are required for the
serial communication network.
Chapter 5 - Start-up Procedure describes
safety, installation inspection, how to check and
setup the communication parameters.
Chapter 6 - Fault Tracing describes
troubleshooting procedures through fault
counters, fault queue, and tracing faults to their
origins.

Chapter 1 – Introduction
1-2 ACS/ACH 400 Direct N2 Bus Interface
Appendix A – Point List lists all the N2 points
from the ACS/ACH 400 drive with the units and
scaling.
Appendix B – DDL File for NCU lists the Data
Definition Language file for the ACS/ACH 400
drive that can be used with the Network
Controller Unit.
Intended Audience The audience for this manual has:
• Knowledge of standard electrical wiring
practices, electronic components, and
electrical schematic symbols.
• Minimal knowledge of ABB product
names and terminology.
• Previous experience in installing,
operating, and programming the
ACS 400 or ACH 400 drives.
The audience for this manual will install, start-
up, and diagnose the drives for the N2 Bus
installation.The audience will also program and
setup the ACS/ACH 400 drives for the
communication network.
Conventions Used
In This Manual Listed below are terms and language
conventions used in this manual. These terms
and conventions are defined here to help you
understand their meanings and applications
throughout this manual.
Analog Inputs Analog Input points are real number values
which are inputs to the Metasys. In the ACS/
ACH 400 drive, the analog input values include
the actual values, and the fault queue entries.
Analog Outputs Analog Output points are real number values
which are outputs from the Metasys. In the
ACS/ACH 400 drive, the analog output values
include the set point values.
Binary Inputs Binary Input points are boolean values which
are inputs to the Metasys. In the ACS/ACH 400
drive, the binary inputs include the drive status
information.

Chapter 1 – Introduction
ACS/ACH 400 Direct N2 Bus Interface 1-3
Binary Outputs Binary Output points are boolean values which
are outputs from the Metasys. In the ACH 400
drive, the binary outputs include the drive
control for start and stop, direction, and fault
reset.
Change of State (COS) On the N2 Bus it is possible to define High and
Low Warning and Alarm limits to analog input
points, and alarm states for binary Inputs.
When a point goes to a Warning or Alarm state,
or returns back from it, the drive will report this
change of state back to the Metasys. This
Change of State (COS) is reported only if this
function is required by the Metasys. This
feature allows fast recognition of changes to
non-normal states, and the subsequent returns
back to normal.
N1LAN N1LAN is the communications backbone for
Metasys. It allows the functions of multiple
Network Control Units and Operator
Workstations to be integrated into a facility-wide
control and information network.
N2Bus The N2 Bus connects point interfaces and
remote controllers within an equipment room, or
within occupied spaces of your facility, to
Network Control Units (NCUs).
On-Line / Off-Line OntheN2 Bus,anode can beeither On-Line or
Off-Line. Immediately after the power-up, every
station is in the Off-Line state. The Metasys
system will then poll all the Off-Line stations.
Once the ACS/ACH 400 has properly
responded to this poll, it is placed into the On-
Line state. In this state the Analog and Binary
points can be read and modified.
When the drive does not respond to the
Metasys for three polls in a row, the drive is
placed into the Off-Line state by the Metasys.

Chapter 1 – Introduction
1-4 ACS/ACH 400 Direct N2 Bus Interface
Terminal Block A terminal block is a group of wire connections
on a drive. This manual expresses specific
terminal blocks and connections as a letter,
usually X, a number, a colon (:), and another
number. The letter and number to the left of the
colon represent the name of the terminal block,
for example, X1. The number to the right of the
colon represents the terminal connection, for
example 4, on the terminal block. In this
manual, a terminal connection numbered 4,
located on a terminal block named X1, is
expressed as X1:4.
Related Publications For related information about the drive, refer to
the ABB User’s Manual for type ACS400
Frequency Cornverter from 2,2 to 37 kW or
ACH 400 AC Drives for Speed Control of 3 to
40 Hp, 230 Volt and 3 to 50 Hp, 460 Volt AC
Induction Motors User’s Manual.

ACS/ACH 400 Direct N2 Bus Interface 2-1
Chapter 2 – Overview of the N2
Connection
This chapter describes the general features of
the N2 Bus. For more detailed information on
the use of the N2 Bus, please consult the
appropriate Johnson Controls documentation.
Introduction The N2 Bus protocol is a master - slave type
serial communication protocol, used by the
Johnson Controls Metasys system. In the
Metasys architecture the N2 Bus connects point
interfaces and remote controllers to Network
Control Units (NCUs).
Also the N2 Bus can be used to connect ACS/
ACH 400 drives to the Johnson Controls
Companion product line.
This chapter is not intended to describe the
protocol in detail, it is intended to describe the
use of the N2 Bus with the ACS/ACH 400
drives’ connection.

Chapter 2 – Overview of the N2 Connection
2-2 ACS/ACH 400 Direct N2 Bus Interface
Metasys Integration Figure 2-1 “ABB and Metasys Integration”
shows the drives’ integration to the Johnson
Controls Metasys system.
Figure 2-1 ABB and Metasys Integration
N1LAN
NCU N2 Bus

Chapter 2 – Overview of the N2 Connection
ACS/ACH 400 Direct N2 Bus Interface 2-3
Figure 2-2 “ABB and Metasys Companion
Integration” shows the drives’ integration to the
Johnson Controls Metasys Companion system.
Figure 2-2 ABB and Metasys Companion Integration
On the N2 Bus each ACS/ACH 400 drive can
be accessed by the full complement of Metasys
FMS features, including Change-of-State
(COS) monitoring, alarm notification,
scheduling, trend, and totalization.
The ACS/ACH 400 drive has a pre-defined set
of Analog and Binary I/O points. A complete list
of these points is in Appendix A of this manual.
On one N2 Bus segment there can be up to 32
nodes while integrating ACS/ACH 400 drives
with Johnson Controls Metasys. This is less
than the 50 nodes which is the recommended
maximum by Johnson Controls.
Device Type For the Metasys and Metasys Companion
products, the device type for the ACS/ACH 400
drive is VND.
PC-Version
Converter
Panel Version/LTD
N2 Bus

Chapter 2 – Overview of the N2 Connection
2-4 ACS/ACH 400 Direct N2 Bus Interface
DDL File To simplify the definition of points for the NCU
unit, the ACH400.DDL file is listed in
Appendix B.

ACS/ACH 400 Direct N2 Bus Interface 3-1
Chapter 3 – Installation
This chapter describes the installationof the N2
network for the ACS/ACH 400 Drives using the
RS-485 connection. It describes the planning of
the network installation, required hardware
wiring, and programming considerations for the
drive.
Introduction The N2 Bus connection to the ACS/ACH 400
drives is based on an industry standard RS-485
physical interface. This chapter will not deal
with Johnson Controls N2 Bus performance or
feature capabilities, but will simply show how
the drives need to be physically wired to the
network.
Network planning should include the following
topics:
• Define the types and quantities of the
devices which will be connected to the
network.
• Define what control information will be
sent down to the drives.
• Define what feedback information will be
sent from the drives to the controlling
system.
During the planning phase, ensure that all NEC
and local code restrictions are followed.
Controlling the drive The drive can receive control through the N2
Bus connection by having the Metasys send
Analog and/or Digital output point values down
to the drive. The control location places must be
setup for COMM for the control information
which needs to be received from the Metasys.
Control actions which are available are
described in detail in Chapter 4 – Programming
of this manual.

Chapter 3 – Installation
3-2 ACS/ACH 400 Direct N2 Bus Interface
Feedback from the
drive The Metasys can read any Analog and Digital
Input point back from the drive.Each one ofthe
Input points on the drive has a predefined
meaning, which is described in Chapter 4 –
Programming in this manual.
Hardware Installation The N2 Bus network is based upon the
industrial RS-485 standard. The RS-485
connection is made using a shielded, twisted
pair cable.
On the N2 Bus for the ACS/ACH 400 drives,
the wiring connections described below are
recommended. This connection method
ensures minimal noise on the network while
keeping the connections simple and affordable.
Wiring The N2 Bus should be wired usingBelden 9842
or equivalent. Belden 9842 is a dual twisted,
shielded pair cable with a wave impedance of
120 W. One of these twisted shielded pairs is
used for the RS-485 link. One of the wires in
the other pair is used for the logical ground,
leaving one wire unused. For details, see the
diagram Figure 3-1 “Communication wiring for
ACS/H 400 Drives”.
The RS-485 link is a daisy-chained bus, without
dropout lines. The RS-485 link should also be
terminated on both physical ends of the wire to
reduce the noise on the network.
Connections The network should be connected according to
the following diagram. In Figure 3-1
“Communication wiring for ACS/H 400 Drives”
the termination resistors are disconnected.