ABB ACS255 User manual

1
ABB Micro drives
User’s manual
ACS255 drives (0.5…10 hp) (115V-480V Variants)

ABB Micro drives
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Code (English)
ACS255 user’s manual for 600V variants
3AXD10000528265

3
ACS255 drives
0.5…10 hp
User’s manual
3AXD10000528266 Rev B
EN
EFFECTIVE: 2017-06-29
©2016 ABB Oy. All Rights Reserved.

4

5
1. Table of Contents
1. Table of Contents __________________________________________________________________5
ACS255 –IP20 (115V) EASY START-UP GUIDE _________________________________________7
ACS255 –IP66 (115-480V Switched Variants) EASY START-UP GUIDE ____________________________8
ACS255 –IP66 (115-480V Non-Switched Variants) EASY START-UP GUIDE ________________________9
2. Safety ___________________________________________________________________________11
2.1. What this chapter contains______________________________________________________________11
2.2. Use of warnings_______________________________________________________________________11
2.3. Safety in installation and maintenance ____________________________________________________11
2.4. Safety in start-up and operation _________________________________________________________12
3. General Information and Ratings _____________________________________________________14
3.1. Type designation key __________________________________________________________________14
3.2. Drive Model Numbers –IP20 ____________________________________________________________15
3.3. Drive Model Numbers –IP66 ____________________________________________________________15
4. Mechanical Installation_____________________________________________________________16
4.1. General _____________________________________________________________________________16
4.2. Mechanical Dimensions and Mounting –IP20 Open Units _____________________________________16
4.3. Guidelines for Enclosure Mounting –IP20 Units _____________________________________________16
4.4. Mechanical Dimensions –IP66 (Nema 4X) Enclosed Units _____________________________________17
4.5. Guidelines for Mounting Enclosed Units ___________________________________________________17
4.6. Gland Plate and Lock Out _______________________________________________________________18
4.7. Removing the Terminal Cover ___________________________________________________________18
5. Power Wiring_____________________________________________________________________19
5.1. Grounding the Drive ___________________________________________________________________19
5.2. Wiring Precautions ____________________________________________________________________20
5.3. Connection Diagram ___________________________________________________________________21
5.4. Drive & Motor Connections _____________________________________________________________22
5.5. Motor Terminal Box Connections_________________________________________________________22
5.6. Using the REV/Off/FWD Selector Switch (IP66 Switched Version Only) __________________________23
6. Control Wiring ____________________________________________________________________24
6.1. Control Terminal Connections ___________________________________________________________24
6.2. RJ45 Data Connection __________________________________________________________________24
7. Operation________________________________________________________________________25
7.1. Managing the Keypad__________________________________________________________________25
7.2. Changing Parameters __________________________________________________________________25
7.3. Resetting to Factory Default Settings______________________________________________________25
8. Quick Start-up and Control __________________________________________________________26
8.1. Quick Start-up Terminal Control _________________________________________________________26

6
8.2. Quick Start-up Keypad Control___________________________________________________________27
9. Application Macros ________________________________________________________________28
9.1. Overview of macros ___________________________________________________________________28
10. Parameters ______________________________________________________________________31
10.1. Parameter Structure ___________________________________________________________________31
10.2. Parameters in the Short parameter mode__________________________________________________32
10.3. Read Only Status parameters____________________________________________________________34
10.4. Parameters in the Long parameter mode __________________________________________________36
10.5. Adjusting the Voltage / Frequency (V/f) characteristics _______________________________________41
10.6. Motor Thermistor Connection ___________________________________________________________41
10.7. Preventing un-authorised parameter editing._______________________________________________42
11. Modbus RTU Communications _______________________________________________________44
11.1. Introduction _________________________________________________________________________44
11.2. Modbus RTU Specification ______________________________________________________________44
11.3. RJ45 Connector Configuration ___________________________________________________________44
11.4. Modbus Telegram Structure_____________________________________________________________44
11.5. Modbus Register Map__________________________________________________________________44
11.6. Modbus Parameter Register Map ________________________________________________________45
12. Technical Data____________________________________________________________________46
12.1. Environmental________________________________________________________________________46
12.2. Rating Tables_________________________________________________________________________46
12.3. Overload ____________________________________________________________________________47
12.4. Additional Information for UL Compliance _________________________________________________47
12.5. Derating Information __________________________________________________________________47
12.6. Mains Line input Reactors ______________________________________________________________48
13. Trouble Shooting __________________________________________________________________50
13.1. Fault Code Messages___________________________________________________________________50

7
ACS255 –IP20 (115V) EASY START-UP GUIDE
Fuses
AC SupplyVoltage
(50/60Hz)
L1
L
L2
N
L3
Earth
M
Supply Voltage :
-115 Volts
-1 Phase
-Check the drive rating information on page 46
Fuses, Cable Sizes :
-Fuse Rating recommendation values given on page 46
-Cable size recommendation values given on page 46
-Always follow local and national codes of practice
Keypad operation can be found in sections 7 and 8
Control Terminals :
Based on the default, out of box settings –
-Connect a Start/Stop switch between terminals 1& 2
-Close the switch to start
-Open the switch to stop
-To vary the speed from minimum (0Hz) to maximum
(60Hz) Connect a 10kΩ potentiometer to terminals 5,6
& 7.
1 2
Stop - Run
65 7
10kΩ
Speed Pot
Motor Cable Sizes
-Cable size recommendation values given on page 46
Motor Connections
-Check for Star or Delta connection according to the
motor voltage rating (See page 22)
Motor Nameplate Details
-Enter the motor rated voltage in parameter 9905
-Enter the motor rated current in parameter 9906
-Enter the motor rated frequency in parameter 9907

8
ACS255 –IP66 (115-480V Switched Variants) EASY START-UP GUIDE
Mechanical Mounting
-Information can be
found on page 17
Keypad operation can be
found in section 7 and 8
Motor Cable Sizes
-Cable size
recommendation values
given on page 46
Motor Connections
-Check for Star or Delta connection
according to the motor voltage rating
(See page 22)
Motor Nameplate Details
-Enter the motor rated voltage in
parameter 9905
-Enter the motor rated current in
parameter 9906
-Enter the motor rated frequency in
parameter 9907
Supply Voltage :
-115, 230, 400, 480 Volts
-1 or 3 Phase
-Check the drive rating
information on page 46
Local Power
disconnect with lock
out provision
Run Reverse / Off / Run Forward Switch
With the factory parameter settings, this
switch allows the drive to be started in
the forward and reverse operating
directions. Alternative switch functions
can be programmed, such as
Local/Remote, hand / Off/ Auto, see page
23.
Local Speed Potentiometer
The local speed potentiometer will adjust
the output frequency from minimum
(Parameter 2007, default setting = 0Hz) to
maximum (Parameter 2008, default
setting = 60Hz)
Fuses
Fuses, Cable Sizes :
-Fuse Rating recommendation values given on page 46
-Cable size recommendation values given on page 46
-Always follow local and national codes of practice.

9
ACS255 –IP66 (115-480V Non-Switched Variants) EASY START-UP GUIDE
Mechanical Mounting
-Information can be found
on page 17
Keypad operation can be
found in sections 7 and 8
Motor Cable Sizes
-Cable size
recommendation values
given on page 46
Motor Connections
-Check for Star or Delta connection
according to the motor voltage
rating (See page 22)
Motor Nameplate Details
-Enter the motor rated voltage in
parameter 9905
-Enter the motor rated current in
parameter 9906
-Enter the motor rated frequency in
parameter 9907
Supply Voltage :
-115, 230, 400, 480 Volts
-1 or 3 Phase
-Check the drive rating
information on page 46
Fuses, Cable Sizes :
-Check the drive rating
information on page 46
Fuses
Fuses, Cable Sizes :
-Fuse Rating recommendation values given on page 46
-Cable size recommendation values given on page 46
-Always follow local and national codes of practice

Declaration of Conformity
The manufacturer hereby states that the ACS255 product range conforms to the relevant safety provisions of the following council directives:
2014/30/EU (EMC) and 2014/35/EU (LVD)
2011/65/EU (RoHS)
EN 61800-5-1: 2007
Adjustable speed electrical power drive systems. Safety requirements. Electrical, thermal and energy.
EN 61800-3 2nd Ed: 2004
/ A1:2012
Adjustable speed electrical power drive systems. EMC requirements and specific test methods
EN 55011: 2007
Limits and Methods of measurement of radio disturbance characteristics of industrial, scientific and
medical (ISM) radio-frequency equipment (EMC)
EN60529 : 1992
Specifications for degrees of protection provided by enclosures
Electromagnetic Compatibility
All drives are designed with high standards of EMC in mind.
It is the responsibility of the installer to ensure that the equipment or system into which the product is incorporated complies with the EMC
legislation of the country of use. Within the European Union, equipment into which this product is incorporated must comply with the EMC
Directive 2004/108/EC. When using an ACS255 with an external filter, compliance with the following EMC Categories, as defined by EN61800-
3:2004 can be achieved:
Drive Type / Rating
EMC Category
First Environment Category C1
First Environment Category C2
Second Environment Category C3
ACS255-_ _U…
Use External EMC Filter Use External EMC Filter Use External EMC Filter
Note
Compliance with EMC standards is dependent on a number of factors including the environment in which the drive is installed,
motor switching frequency, motor, cable lengths and installation methods adopted.
For shielded motor cable lengths greater than 100m and up to 200m, an output dv/dt filter must be used (please refer to
http://www.abb.com/ProductGuide for further details)
All rights reserved. No part of this User Guide may be reproduced or transmitted in any form or by any means, electrical or mechanical
including photocopying, recording or by any information storage or retrieval system without permission in writing from the publisher.
ABB Drives Ltd © 2016
The manufacturer accepts no liability for any damage caused during or resulting from transport, receipt of delivery, installation or
commissioning. The manufacturer also accepts no liability for damage or consequences resulting from inappropriate, negligent or incorrect
installation, incorrect adjustment of the operating parameters of the drive, incorrect matching of the drive to the motor, incorrect installation,
unacceptable dust, moisture, corrosive substances, excessive vibration or ambient temperatures outside of the design specification.
The contents of this User Guide are believed to be correct at the time of printing. In the interest of a commitment to a policy of continuous
improvement, the manufacturer reserves the right to change the specification of the product or its performance or the contents of the User
Guide without notice.
This User Guide is for use with version 2.0x Software.
User Guide Revision B
This user guide is the “original instructions” document. All non-English versions are translations of the “original instructions”.
The manufacturer adopts a policy of continuous improvement and whilst every effort has been made to provide accurate and up to date
information, the information contained in this User Guide should be used for guidance purposes only and does not form the part of any
contract.

11
2. Safety
2.1. What this chapter contains
This chapter contains the safety instructions which you must follow when installing, operating and servicing the drive. If
ignored, physical injury or death may follow, or damage may occur to the drive, motor or driven equipment. Read the
safety instructions before you work on the unit.
2.2. Use of warnings
Warnings caution you about conditions which can result in serious injury or death and/or damage to the equipment and
advice on how to avoid the danger. The following warning symbols are used in this manual:
Electricity warning warns of hazards from electricity which can cause physical injury and/or damage to
the equipment.
General warning warns about conditions, other than those caused by electricity, which can result in
physical injury and/or damage to the equipment.
2.3. Safety in installation and maintenance
These warnings are intended for all who work on the drive, motor cable or motor.
Electricity safety
Never work on the drive, motor cable or motor when input power is applied. After disconnecting the input power, always
wait for 10 minutes to let the intermediate circuit capacitors discharge before you start working on the drive, motor or
motor cable.
Always ensure by measuring with a multimeter (impedance at least 1 Mohm) that:
1. There is no voltage between the drive input phases L1, L2 and L3 and the ground.
2. There is no voltage between terminals + and BR and the ground.
Do not work on the control cables when power is applied to the drive or to the external control circuits. Externally supplied
control circuits may carry dangerous voltage even when the input power of the drive is switched off.
Do not make any insulation or voltage withstand tests on the drive.
Be sure the system is properly grounded before applying power. Do not apply AC power before you ensure that all
grounding instructions have been followed. Electrical shock can cause serious or fatal injury.
Note:
Even when the motor is stopped, dangerous voltage is present at the power circuit terminals L1, L2, L3 and U, V, W and + and BR.
WARNING! Ignoring the instructions can cause physical injury or death, or damage to the equipment.
Only qualified electricians are allowed to install and maintain the drive!

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General safety
WARNING! Ignoring the following instructions can cause physical injury or death, or damage to the equipment.
The drive is not field repairable. Never attempt to repair a malfunctioning drive; contact your local ABB representative or
Authorized Service Centre for replacement.
Make sure that dust from drilling does not enter the drive during the installation. Electrically conductive dust inside the drive
may cause damage or lead to malfunction.
Ensure sufficient cooling.
2.4. Safety in start-up and operation
These warnings are intended for all who plan the operation, start up or operate the drive.
WARNING! Ignoring the following instructions can cause physical injury or death, or damage to the equipment.
Before adjusting the drive and putting it into service, make sure that the motor and all driven equipment are suitable for
operation throughout the speed range provided by the drive. The drive can be adjusted to operate the motor at speeds
above and below the speed provided by connecting the motor directly to the power line.
Do not activate automatic fault reset functions if dangerous situations can occur. When activated, these functions reset the
drive and resume operation after a fault.
Do not control the motor with an AC contactor or disconnecting device (disconnecting means); use instead the control
panel start and stop keys and or external commands (I/O). The maximum allowed number of charging cycles of the DC
capacitors (that is, power-ups by applying power) is two per minute.
Note:
When parameter 1103 PRIMARY COMMAND SOURCE MODE is not set to 1 or 2, the stop key on the control panel will not
stop the drive. To stop the drive open terminal 2 of the drive control terminals.

13
Danger: Indicates a risk of electric shock, which, if not
avoided, could result in damage to the equipment and
possible injury or death.
Danger: Indicates a potentially hazardous situation
other than electrical, which if not avoided, could result
in damage to property.
The ACS255 variable speed drive is intended for professional installation and commissioning into complete equipment or systems
as part of a fixed installation. If installed incorrectly it may present a safety hazard. The ACS255 uses high voltages and currents,
carries a high level of stored electrical energy, and is used to control mechanical plant that may cause injury. Close attention is
required to system design and electrical installation to avoid hazards in either normal operation or in the event of equipment
malfunction. Only qualified electricians are allowed to install and maintain this product.
System design, installation, commissioning and maintenance must be carried out only by personnel who have the necessary
training and experience. They must carefully read this safety information and the instructions in this Guide and follow all
information regarding transport, storage, installation and use of the ACS255, including the specified environmental limitations.
Do not perform any flash test or voltage withstand test on the ACS255. Any electrical measurements required should be carried out
with the ACS255 disconnected.
Electric shock hazard! Disconnect and ISOLATE the ACS255 before attempting any work on it. High voltages are present at the
terminals and within the drive for up to 10 minutes after disconnection of the electrical supply. Always ensure by using a suitable
multimeter that no voltage is present on any drive power terminals prior to commencing any work.
Where supply to the drive is through a plug and socket connector, do not disconnect until 10 minutes have elapsed after turning off
the supply.
Ensure correct grounding connections. The ground cable must be sufficient to carry the maximum supply fault current which
normally will be limited by the fuses. Suitably rated fuses should be fitted in the mains supply to the drive, according to any local
legislation or codes.
Do not carry out any work on the drive control cables when power is applied to the drive or to the external control circuits.
Within the European Union, all machinery in which this product is used must comply with the Machinery Directive 2006/42/EC,
Safety of Machinery. In particular, the machine manufacturer is responsible for providing a main switch and ensuring the electrical
equipment complies with EN60204-1.
The level of integrity offered by the ACS255 control input functions –for example stop/start, forward/reverse and maximum speed
is not sufficient for use in safety-critical applications without independent channels of protection. All applications where
malfunction could cause injury or loss of life must be subject to a risk assessment and further protection provided where needed.
The driven motor can start at power up if the enable input signal is present.
The STOP function does not remove potentially lethal high voltages. ISOLATE the drive and wait 10 minutes before starting any
work on it. Never carry out any work on the Drive, Motor or Motor cable when the input power is still applied.
The ACS255 can be programmed to operate the driven motor at speeds above or below the speed achieved when connecting the
motor directly to the mains supply. Obtain confirmation from the manufacturers of the motor and the driven machine about
suitability for operation over the intended speed range prior to machine start up.
Do not activate the automatic fault reset function on any systems whereby this may cause a potentially dangerous situation.
The ACS255 has an Ingress Protection rating of IP20 or IP66 depending on the model. IP20 units must be installed in a suitable
enclosure.
ACS255s are intended for indoor use only.
When mounting the drive, ensure that sufficient cooling is provided. Do not carry out drilling operations with the drive in place,
dust and metal shavings from drilling may lead to damage.
The entry of conductive or flammable foreign bodies should be prevented. Flammable material should not be placed close to the
drive
Relative humidity must be less than 95% (non-condensing).
Ensure that the supply voltage, frequency and number of phases correspond to the rating of the ACS255 as delivered.
Never connect the mains power supply to the Output terminals U, V, W.
Do not install any type of automatic switchgear between the drive and the motor
Wherever control cabling is close to power cabling, maintain a minimum separation of 4 in. (100 mm) and arrange crossings at 90
degrees
Ensure that all terminals are tightened to the appropriate torque setting
Do not attempt to carry out any repair of the drive. In the case of suspected fault or malfunction, contact your local ABB
representative for further assistance.

14
3. General Information and Ratings
This chapter contains information about the ACS255 including how to identify the drive.
3.1. Type designation key
The type designation contains information on the specification and configuration of the drive. You find the type designation label attached to
the drive. The first digits from the left express the basic configuration, for example ACS255-03U-05A8-4.
The explanations of the type designation label selections are described below.
ACS255-03 U-05A8-4+B063+F278+N828
ACS255 product series
1-phase/3 phase
01 = 1-phase input
03 = 3-phase input
EMC Filter
E = Filtered
U = Non-Filtered
Output Current Rating
In format xxAy, where xx indicates the integer part and y the fractional part,
For example, 05A8 means 5.8 A.
Input Voltage Range
1 = 110…115 V AC
2 = 200…240 V AC
4 = 380…480VAC
IP66 Enclosure
Input Switch Assembly
(Speed potentiometer, run/stop and mains disconnect switch)
Low ambient Temperature version (-20deg C)

15
3.2. Drive Model Numbers –IP20
Mechanical Dimensions and Mounting information are shown in section 4.
Further Electrical Specifications are shown in section 12.2.
Model Number
Power
(HP)
Output
Current
(A)
Input switch assembly
Internal DB
transistor
Frame Size
1-phase 110V…115V AC (+/-10%) - 3 Phase 230V Output
ACS255-01U-02A3-1
0.5
2.3
No
No
E1
ACS255-01U-04A3-1
1
4.3
No
No
E1
ACS255-01U-05A8-1
1.5
5.8
No
Yes
E2
3.3. Drive Model Numbers –IP66
Mechanical Dimensions and Mounting information are shown in section 4.
Further Electrical Specifications are shown in section 12.2.
Model Number
Power
(HP)
Output
Current
(A)
Input switch assembly
Internal DB
transistor
Frame Size
1-phase 110V…115V AC (+/-10%) - 3 Phase 230V Output
ACS255-01U-02A3-1+B063
0.5
2.3
No
No
E1
ACS255-01U-02A3-1+B063+F278
0.5
2.3
Yes
No
E1
ACS255-01U-04A3-1+B063
1
4.3
No
No
E1
ACS255-01U-04A3-1+B063+F278
1
4.3
Yes
No
E1
ACS255-01U-05A8-1+B063
1.5
5.8
No
Yes
E2
ACS255-01U-05A8-1+B063+F278
1.5
5.8
Yes
Yes
E2
1-phase 200…240V AC (+/-10%) - 3 Phase Output
ACS255-01U-02A3-2+B063
0.5
2.3
No
No
E1
ACS255-01U-02A3-2+B063+F278
0.5
2.3
Yes
No
E1
ACS255-01U-04A3-2+B063
1
4.3
No
No
E1
ACS255-01U-04A3-2+B063+F278
1
4.3
Yes
No
E1
ACS255-01U-06A1-2+B063
1.5
6.1
No
No
E1
ACS255-01U-06A1-2+B063+F278
1.5
6.1
Yes
No
E1
ACS255-01U-07A0-2+B063
2
7
No
No
E1
ACS255-01U-07A0-2+B063+F278
2
7
Yes
No
E1
ACS255-01U-07A0-2+B063+D150
2
7
No
Yes
E2
ACS255-01U-07A0-2+B063+F278+D150
2
7
Yes
Yes
E2
ACS255-01U-10A5-2+B063
3
10.5
No
Yes
E2
ACS255-01U-10A5-2+B063+F278
3
10.5
Yes
Yes
E2
ACS255-01U-15A3-2+B063
5
15.3
No
Yes
E3
ACS255-01U-15A3-2+B063+F278
5
15.3
Yes
Yes
E3
3-phase 200…240V AC (+/-10%) - 3 Phase Output
ACS255-03U-02A3-2+B063
0.5
2.3
No
No
E1
ACS255-03U-02A3-2+B063+F278
0.5
2.3
Yes
No
E1
ACS255-03U-04A3-2+B063
1.0
4.3
No
No
E1
ACS255-03U-04A3-2+B063+F278
1.0
4.3
Yes
No
E1
ACS255-03U-06A1-2+B063
1.5
6.1
No
No
E1
ACS255-03U-06A1-2+B063+F278
1.5
6.1
Yes
No
E1
ACS255-03U-07A0-2+B063
2
7
No
Yes
E2
ACS255-03U-07A0-2+B063+F278
2
7
Yes
Yes
E2
ACS255-03U-10A5-2+B063
3
10.5
No
Yes
E2
ACS255-03U-10A5-2+B063+F278
3
10.5
Yes
Yes
E2
ACS255-03U-18A0-2+B063
5
18
No
Yes
E3
ACS255-03U-18A0-2+B063+F278
5
18
Yes
Yes
E3
3-phase 380…480V AC (+/-10%) - 3 Phase Output
ACS255-03U-01A2-4+B063
0.5
1.2
No
No
E1
ACS255-03U-01A2-4+B063+F278
0.5
1.2
Yes
No
E1
ACS255-03U-02A2-4+B063
1
2.2
No
No
E1
ACS255-03U-02A2-4+B063+F278
1
2.2
Yes
No
E1
ACS255-03U-03A3-4+B063
1.5
3.3
No
No
E1
ACS255-03U-03A3-4+B063+F278
1.5
3.3
Yes
No
E1
ACS255-03U-04A1-4+B063
2
4.1
No
No
E1
ACS255-03U-04A1-4+B063+F278
2
4.1
Yes
No
E1
ACS255-03U-04A1-4+B063+D150
2
4.1
No
Yes
E2
ACS255-03U-04A1-4+B063+F278+D150
2
4.1
Yes
Yes
E2
ACS255-03U-05A8-4+B063
3
5.8
No
Yes
E2
ACS255-03U-05A8-4+B063+F278
3
5.8
Yes
Yes
E2
ACS255-03U-09A5-4+B063
5
9.5
No
Yes
E2
ACS255-03U-09A5-4+B063+F278
5
9.5
Yes
Yes
E2
ACS255-03U-14A0-4+B063
7.5
14
No
Yes
E3
ACS255-03U-14A0-4+B063+F278
7.5
14
Yes
Yes
E3
ACS255-03U-18A0-4+B063
10
18
No
Yes
E3
ACS255-03U-18A0-4+B063+F278
10
18
Yes
Yes
E3

16
4. Mechanical Installation
4.1. General
Carefully Unpack the ACS255 and check for any signs of damage. Notify the shipper immediately if any exist.
Check the drive rating label to ensure it is of the correct type and power requirements for the application.
Store the ACS255 in its box until required. Storage should be clean and dry and within the temperature range –40°C to +60°C
The ACS255 should be mounted in a vertical position only on a flat, flame resistant vibration free mounting using the integral holes.
The ACS255 must be installed in a pollution degree 1 or 2 environment only.
Do not mount flammable material close to the ACS255
Ensure that the minimum cooling air gaps, as detailed in sections 4.3 and 4.5 are left clear
Ensure that the ambient temperature range does not exceed the permissible limits for the ACS255 given on page 46.
Provide suitable clean, moisture and contaminant free cooling air sufficient to fulfil the cooling requirements of the ACS255
according to sections 4.3 and 12.1.
4.2. Mechanical Dimensions and Mounting –IP20 Open Units
H
G
D
C
E
I
J
B
H
A
F
Drive
Frame
Size
A
B
C
D
E
F
G
H
I
J
Weight
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
Kg
Ib
1
173
6.81
160
6.30
109
4.29
162
6.38
5
0.20
123
4.84
82
3.23
50
1.97
5.5
0.22
10
0.39
1.0
2.20
2
221
8.70
207
8.15
137
5.39
209
8.23
5.3
0.21
150
5.91
109
4.29
63
2.48
5.5
0.22
10
0.39
1.7
3.75
NOTE
Maximum Control Terminal Torque Settings of 0.5 Nm (4.5 lb-in)
Maximum Power Terminal Torque Settings of 1 Nm (9 lb-in)
4.3. Guidelines for Enclosure Mounting –IP20 Units
Installation should be in a suitable enclosure, according to EN60529 or other relevant local codes or standards.
Enclosures should be made from a thermally conductive material.
Where vented enclosures are used, there should be free space clearance above and below the drive to ensure good air circulation –
see the diagram below for minimum free space clearance. Air should be drawn in below the drive and expelled above the drive.
In any environments where the conditions require it, the enclosure must be designed to protect the ACS255 against ingress of
airborne dust, corrosive gases or liquids, conductive contaminants (such as condensation, carbon dust, and metallic particles) and
sprays or splashing water from all directions.
High moisture, salt or chemical content environments should use a suitably sealed (non-vented) enclosure.
The enclosure design and layout should ensure that the adequate ventilation paths and clearances are left to allow air to circulate through the
drive heatsink. ABB Drives recommend the following minimum mounting clearance requirements for drives mounted in non-ventilated
metallic enclosures:-
Z
X
YY
X
Drive
Size
X
Above &
Below
Y
Either
Side
Z
Between
mm
in
mm
in
mm
in
1
50
1.97
50
1.97
33
1.30
2
75
2.95
50
1.97
46
1.81
Note :
Dimension Z assumes that the drives are mounted side-by-side with
no clearance.
Typical drive heat losses are 3% of operating load conditions.
Above are guidelines only and the operating ambient temperature of
the drive MUST be maintained at all times.

17
4.4. Mechanical Dimensions –IP66 (Nema 4X) Enclosed Units
D
B
E
H
G
I
J
F
A
Drive
Frame
Size
A
B
D
E
F
G
H
I
J
Weight
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
mm
in
kg
Ib
1
232.0
9.13
207.0
8.15
189.0
7.44
25.0
0.98
179.0
7.05
161.0
6.34
148.5
5.85
4.0
0.16
8.0
0.31
2.95
6.50
2
257.0
10.12
220.0
8.67
200.0
7.87
28.5
1.12
186.5
7.34
188.0
7.40
176.0
6.93
4.2
0.17
8.5
0.33
4.20
9.26
3
310.0
12.2
276.5
10.89
251.5
9.90
33.4
1.31
252
9.92
210.5
8.29
197.5
7.78
4.2
0.17
8.5
0.33
7.7
17
NOTE
The size 3 product has 4 symmetrical mounting points
Maximum Control Terminal Torque Settings of 0.5 Nm (4.5 lb-in)
Maximum Power Terminal Torque Settings of 1 Nm (9 lb-in)
4.5. Guidelines for Mounting Enclosed Units
Before mounting the drive, ensure that the chosen location meets the
environmental condition requirements for the drive shown in section 12.1
The drive must be mounted vertically, on a suitable flat surface
The minimum mounting clearances as shown in the table below must be
observed
The mounting site and chosen mountings should be sufficient to support
the weight of the drives
The Enclosed ACS255s can be installed side-by-side with their heatsink
flanges touching. This gives adequate ventilation space between drives.
If the ACS255 is to be installed above another drive or any other heat-
producing device, the minimum vertical spacing (X) is 150mm (5.9 inches)
above and below.
X
X

18
4.6. Gland Plate and Lock Out
The use of a suitable gland system is required to maintain the appropriate IP / Nema rating. The gland plate has pre moulded cable entry holes
for power and motor connections suitable for use with glands as shown in the following table. Where additional holes are required, these can
be drilled to suitable size. Please take care when drilling to avoid leaving any particles within the product.
Cable Gland recommended Hole Sizes & types:
Moulded Hole Size
UL Gland Size
Metric Gland Size
Frame Size 1
0.866in (22mm)
PG13.5
M20
Frame Size 2 & 3
1.11in (28.2mm)
PG21
M25
Drill Size
UL Gland Size
Metric
Flexible Conduit Hole Size
Frame Size 1
1.125in (28mm)
¾ in
21
Frame Size 2 & 3
1.375in (35mm)
1 in
27
UL rated ingress protection ("Type " ) is only met when cables are installed using a UL recognized bushing or fitting for a flexible-
conduit system which meets the required level of protection ("Type")
For conduit installations the conduit entry holes require standard opening to the required sizes specified per the NEC.
Not intended for rigid conduit system
Local Power Isolator Lock out
On the switched models the Local Power Isolator switch can be locked in the ‘Off’ position using a 20mm standard shackle padlock (not
supplied).
IP66 / Nema 12 Unit Lock Out
IP66 / Nema 4X Unit Lock Out
4.7. Removing the Terminal Cover
To access the connection terminals, the drive front cover needs to be removed as shown.
IP66 / NEMA 4X Units
Removing the 2 screws on the front of the product allows access to the connection terminals, as shown below.

19
5. Power Wiring
5.1. Grounding the Drive
This manual is intended as a guide for proper installation. ABB Drives Ltd cannot assume responsibility for the compliance or
the non-compliance to any code, national, local or otherwise, for the proper installation of this drive or associated equipment.
A hazard of personal injury and/or equipment damage exists if codes are ignored during installation.
This ACS255 contains high voltage capacitors that take time to discharge after removal of the main supply. Before working on
the drive, ensure isolation of the main supply from line inputs. Wait ten (10) minutes for the capacitors to discharge to safe
voltage levels. Failure to observe this precaution could result in severe bodily injury or loss of life.
Only qualified electrical personnel familiar with the construction and operation of this equipment and the hazards involved
should install, adjust, operate, or service this equipment. Read and understand this manual and other applicable manuals in
their entirety before proceeding. Failure to observe this precaution could result in severe bodily injury or loss of life.
5.1.1. Recommended installation for EMC compliance
Whenever possible use Shielded motor cables-
maintaining shield as far as possible along the cable.
=/>100mm
 Twisted-Pair shielded cables for analog control and motor
feedback signals.
 Ensure Filter chassis is making metal-metal contact with
Mounting panel.
RFI Filter
Option
Site Ground Bus-Bar bonded to Metal Back-Panel
panel which is bonded to main power ground.
U V W PE U V W PE
360° bonding
EMC cable gland
(Best-Practice)
(Shield to Motor
Chassis)
X
 Avoid long parallel
runs of motor cables
with other cables
 Where control cables must cross power
cables make sure they are arranged at an
angle as near to 90 degrees as possible.
Metal Back-Panel

20
5.1.2. Grounding Guidelines
The ground terminal of each ACS255 should be individually connected DIRECTLY to the site ground bus bar (through the filter if installed).
ACS255 ground connections should not loop from one drive to another, or to, or from any other equipment. Ground loop impedance must
confirm to local industrial safety regulations. To meet UL regulations, UL approved ring crimp terminals should be used for all ground wiring
connections.
The drive Safety Ground must be connected to system ground. Ground impedance must conform to the requirements of national and local
industrial safety regulations and/or electrical codes. The integrity of all ground connections should be checked periodically.
5.1.3. Protective Earth Conductor
The Cross sectional area of the PE Conductor must be at least equal to that of the incoming supply conductor.
5.1.4. Safety Ground
This is the safety ground for the drive that is required by code. One of these points must be connected to adjacent building steel (girder, joist),
a floor ground rod, or bus bar. Grounding points must comply with national and local industrial safety regulations and/or electrical codes.
The safety ground terminal provides a grounding point for the motor cable shield. The motor cable shield connected to this terminal (drive
end) should also be connected to the motor frame (motor end). Use a shield terminating or EMI clamp to connect the shield to the safety
ground terminal.
5.1.5. Motor Ground
The motor ground must be connected to one of the ground terminals on the drive.
5.1.6. Ground Fault Monitoring
As with all inverters, a leakage current to earth can exist. The ACS255 is designed to produce the minimum possible leakage current while
complying with worldwide standards. The level of current is affected by motor cable length and type, the effective switching frequency, the
earth connections used and the type of RFI filter installed. If a GFCI (Ground Fault Current interrupter) is to be used, the following conditions
apply: -
The device must be suitable for protecting equipment with a DC component in the leakage current
Individual GFCI’s should be used for each ACS255
The ACS255 product range has input supply voltage surge suppression components fitted to protect the drive from line voltage transients,
typically originating from lightning strikes or switching of high power equipment on the same supply.
5.2. Wiring Precautions
Connect the ACS255 according to sections 5.3 and 5.4, ensuring that motor terminal box connections are correct. There are two connections in
general: Star and Delta. It is essential to ensure that the motor is connected in accordance with the voltage at which it will be operated. For
more information, refer to section 5.5.
Type MC continuous corrugated aluminium armor cable with symmetrical grounds or shielded power cable is recommended for the motor
cables if metallic conduit is not used.
The power cables must be rated for 75˚C (167˚F).
5.2.1. EMC Filters
WARNING! EMC filters should not be used when there is a risk that the phase to earth voltage could exceed the phase to
phase voltage, Typically IT (ungrounded) and corner-grounded TN systems, otherwise this may cause danger or damage to
the EMC filter.