Rockwell Automation 1336T User Manual

Installation Instructions

Wiring and Grounding Guidelines for Pulse Width Modulated (PWM) AC Drives

Important User Information

IMPORTANT

Read this document and the documents listed in the additional resources section about installation, configuration, and operation of this equipment before you install, configure, operate, or maintain this product. Users are required to familiarize themselves with installation and wiring instructions in addition to requirements of all applicable codes, laws, and standards.

Activities including installation, adjustments, putting into service, use, assembly, disassembly, and maintenance are required to be carried out by suitably trained personnel in accordance with applicable code of practice.

If this equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired.

In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment.

The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or liability for actual use based on the examples and diagrams.

No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or software described in this manual.

Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation, Inc., is prohibited.

Throughout this manual, when necessary, we use notes to make you aware of safety considerations.

WARNING: Identifies information about practices or circumstances that can cause an explosion in a hazardous environment, which may lead to personal injury or death, property damage, or economic loss.

ATTENTION: Identifies information about practices or circumstances that can lead to personal injury or death, property damage, or economic loss. Attentions help you identify a hazard, avoid a hazard, and recognize the consequence.

Identifies information that is critical for successful application and understanding of the product.

Labels may also be on or inside the equipment to provide specific precautions.

SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous voltage may be present.

BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may reach dangerous temperatures.

ARC FLASH HAZARD: Labels may be on or inside the equipment, for example, a motor control center, to alert people to potential Arc Flash. Arc Flash will cause severe injury or death. Wear proper Personal Protective Equipment (PPE). Follow ALL Regulatory requirements for safe work practices and for Personal Protective Equipment (PPE).

Allen-Bradley, Rockwell Software, PartnerNetwork, PowerFlex, and Rockwell Automation are trademarks of Rockwell Automation, Inc.

Trademarks not belonging to Rockwell Automation are property of their respective companies.

Summary of Changes

The information below summarizes the changes to this manual since the last release.

New and Updated Information

Top ic Pag e

Added PowerFlex 525, PowerFlex 753, and PowerFlex 755 drives to the motor cable length cross referenc e table.

Added motor cable length restriction tables for PowerFlex 525 drives.

Table 23, 400V (frames A…E) 90

Table 24, 480V (frames A…E) 91

Table 25, 600V (frames A…E) 92

Updated motor cable length restriction tables for PowerFlex 700H drives.

Table 32, 600V (frames 9…13) 100

Table 33, 690V (frames 9…13) 100

Updated motor cable length restriction tables for PowerFlex 700S drives.

Table 44, 600V (frames 3…13) 107

Table 45, 690V (frames 5…13) 108

Added motor cable length restriction tables for PowerFlex 753 and 755 wall mount drives.

Table 46, 400V (frames 1 and 2) 109

Table 47, 480V (frames 1 and 2) 111

Table 48, 600V (frames 3…7) 114

Table 49, 690V (frames 6 and 7) 117

Added motor cable length restriction tables for PowerFlex 755 floor mount drives.

Table 50, 400V (frames 9 and 10) 118

Table 51, 480V (frames 9 and 10) 120

Table 52, 600V (frames 8…10) 121

Table 53, 690V (frames 8…10) 123

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 3

Summary of Changes

Notes:

4 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Preface

Wire/Cable Types

About This Publication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Intended Audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Recommended Cable/Wire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Chapter 1

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Exterior Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Temperature Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Number of Conductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Insulation Thickness and Concentricity . . . . . . . . . . . . . . . . . . . . . . . . 14

Geometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Unshielded Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Shielded Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Armored Cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

European Style Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Input Power Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Motor Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Cable for Discrete Drive I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Analog Signal and Encoder Cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

DeviceNet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

ControlNet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Remote I/O and Data Highway Plus (DH+) . . . . . . . . . . . . . . . . . . . 24

Serial (RS-232 and RS-485) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Power Distribution

Chapter 2

System Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Delta/Wye with Grounded Wye Neutral. . . . . . . . . . . . . . . . . . . . . . . 25

Delta/Delta with Grounded Leg,

or Four-wire Connected Secondary Delta . . . . . . . . . . . . . . . . . . . . . . 26

Three-phase Open Delta with Single-phase Center Tapped . . . . . . 26

Ungrounded Secondary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

High Resistance Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

TN-S Five-wire System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

AC Line Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

AC Line Impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Multi-drive Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Surge Protection MOVs and Common Mode Capacitors. . . . . . . . . . . . 45

Use PowerFlex Drives with Regenerative Units . . . . . . . . . . . . . . . . . . . . . 46

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 5

Table of Contents

Grounding

DC Bus Wiring Guidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Drive Lineup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

DC Bus Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Chapter 3

Grounding Safety Grounds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Building Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Grounding PE or Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

RFI Filter Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Grounding Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Grounding and TN-S Five-wire Systems . . . . . . . . . . . . . . . . . . . . . . . . 50

Noise Related Grounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Acceptable Grounding Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Effective Grounding Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Optimal – Recommended Grounding Practices . . . . . . . . . . . . . . . . . 54

Cable Shields. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Isolated Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Best Practices

Chapter 4

Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Standard Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

EMC Specific Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Conduit Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Entry Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Cable Connectors/Glands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Shield Termination via Pigtail (lead) . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Ground Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Wire Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Within A Cabinet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Within Conduit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Loops, Antennas, and Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Conduit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Cable Trays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Shield Termination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Termination via Circular Clamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Shield Termination via Pigtail (lead) . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Shield Termination via Cable Clamp . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Conductor Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Power TB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Control TB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Signal TB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Moisture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

6 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Chapter 5

Table of Contents

Reflected Wave

Electromagnetic Interference

Motor Cable Length Restrictions Tables

Glossary

Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Effects On Wire Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Length Restrictions For Motor Protection . . . . . . . . . . . . . . . . . . . . . . . . . 74

Chapter 6

What Causes Common Mode Noise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Containing Common Mode Noise With Cabling. . . . . . . . . . . . . . . . . . . 76

Conduit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Shielded or Armored Power Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

How Electromechanical Switches Cause Transient Interference. . . . . . 77

How to Prevent or Mitigate Transient Interference from

Electromechanical Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Enclosure Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Bearing Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Appendix A

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Motor Cable Length Restrictions Tables Cross Reference. . . . . . . . 83

PowerFlex 4 Drives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

PowerFlex 4M Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

PowerFlex 40 Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

PowerFlex 400 Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

PowerFlex 525 Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

PowerFlex 70 and 700 Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

PowerFlex 700H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

PowerFlex 700L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

PowerFlex 700S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

PowerFlex 753 and 755 Wall Mount Drives . . . . . . . . . . . . . . . . . . . . . . . 109

PowerFlex 755 Floor Mount Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

1336 PLUS II and IMPACT Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

1305 Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

160 Drives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

Reflected Wave Reduction Guidelines

(for catalog number 1321-RWR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Index

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 7

Table of Contents

Notes:

8 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Preface

About This Publication

This manual provides the basic information needed to properly install, protect, wire, and ground pulse width modulated (PWM) AC drives.

Intended Audience

This manual is intended for qualified personnel who plan and design installations of PWM AC drives.

Additional Resources

These documents contain additional information concerning related products from Rockwell Automation.

Resource Description

Safety Guidelines for the Ap plication, Installation and Maintenance of Solid State Control, publication SGI-1.1

Don’t Ignore the Cost of Power Line Disturbance, publication 1321-TD001 Provides technical data on Allen-Bradley power conditioning products.

IEEE Guide for the Installation of Electrical Equipment to Minimize Electrical Noise Inputs to Controllers from External Sources, publication IEEE 518. Availa ble from IEEE Xplore Digital Librar y.

Recommended Practice for Powering and Grounding Electronic Equipment - IEEE Emerald Book, publication IEEE STD 1100. Available from IEEE Xplore Digital Library

IEEE Recommended Practice for Grounding of Industrial and Commercial Power Systems, publication IEEE Std 142-1991. Available from IEEE Xplore Digital Library

Cable Alternatives for PWM AC Drive Applications, publication IEEE Paper No. PCIC-99-23. Available from IEEE Xplore Digital Library

EMI Emissions of Modern PWM AC Drives

IEEE Industry Applications Magazine

Electromagnetic Interference and Compatibility, Volume 3, by Donald R. J. White This book provides information EMI control methods and techniques.

Grounding, Bonding, and Shielding for Electronic Equipment and Facilities (Military Handbook 419)

Noise Reduction Techniques in Electronic Systems by Henry W. Ott This book provides information on controlling emissions from electronic systems, and

Grounding for the Control of EMI by Hugh W. Denny This book provides grounding guidelines for the control of EMI.

EMC for Product Designers by Tim Williams This book provides the information needed to meet the requirements of the latest EMC

National Electrical Code (ANSI/NFPA 70) Articles 250, 725-5, 725-15, 725-52 and 800-52 (www.nfpa.org)

Application Guide for AC Adjustable Speed Drive Systems, NEMA (www.nema.org

IEC 60364-5-52 Selection and Erection of Electrical Equipment - Wiring systems, IEC (www.iec.ch)

, Nov./Dec. 1999

Provides general guidelines for the application, installation, and maintenance of solid-state control devices or assemblies.

Provides techniques for installing controllers and control systems so that proper operation can be achieved in the presence of electrical noise.

Provides the recommended practices for powering and groundiing electronic equipment.

Provides recommended practices to ground power systems.

Describes an alternative solution for cables used with IGBT variable frequency drives (VFDs).

Provides an understanding of EMI issues and with pre-installation and post-installation guidelines.

Provides grounding, bonding, and shielding applications for communication electronics equipments and facilities.

techniques for providing electromagnetic compatibility (EMC).

directive.

Provides information on the installation of electrical components, signaling and communication conductors and grounding.

Provides a NEMA applicatio n guide for AC drive systems.

IEC wiring systems.

You can view or download publications at

http:/www.rockwellautomation.com/literature/

. To order paper copies of technical documentation, contact your local Allen-Bradley distributor or Rockwell Automation sales representative.

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 9

Preface

Recommended Cable/Wire

General Precautions

The recommended wire and cable referenced in this publication can be obtained from third-party companies found in our PartnerNetwork™ Encompass Program.

For further information on these suppliers and their products, follow these steps to find recommended wire and cable for your drives.

1. Go to the Encompass website at http://www.rockwellautomation.com/

rockwellautomation/sales-partners/complementary-products/ overview.page.

2. Under Find an Encompass Referenced Product, click FIND NOW.

3. In the Product Category pull-down list, choose Drive - Cables.

4. Click SEARCH.

ATT EN TI ON : To avoid an electric shock hazard, verify that the voltage on the bus capacitors has discharged before performing any work on the drive. Measure the DC bus voltage at the +DC and –DC terminals of the power terminal block. The voltage must be zero.

10 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Chapter 1

Wire/Cable Types

AC drive installations have specific wire and cable requirements. This section includes information about the major issues for proper selection of cable, and provides recommendations to address these issues. Consider these conditions and requirements when choosing cable material and construction for your installation:

• Environment – such as moisture, temperature, and harsh or corrosive chemicals.

• Mechanical needs – such as geometry, shielding, flexibility, and crush resistance.

• Electrical characteristics – such as cable capacitance/charging current, resistance/voltage drop, current rating, and insulation. Insulation can be the most significant of these. Because drives can create voltages in excess of line voltage, the industry standard cables that were used in the past are not the best choice for variable speed drives. Drive installations benefit from cable that is significantly different than cable used to wire contactors and push buttons.

• Safety issues – such as electrical code requirements, grounding needs, and others.

General

Choosing incorrect cabling can be costly and can adversely affect the performance of your installation.

Material

Use only copper wire. The wire clamp-type terminals in Allen-Bradley drives are made for use with copper wire. If you use aluminum wire, the connections can loosen and cause premature equipment failure.

Wire gauge requirements and recommendations are based on 75 °C (167 °F) rating. Do not reduce wire gauge when you use higher temperature wire.

Exterior Cover

Whether shielded or unshielded, the cable must meet all of the application requirements. Consider insulation value and resistance to moisture, contaminants, corrosive agents, and other invasive elements. Consult the cable manufacturer and Figure 1 on page 12

for cable selection criteria.

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 11

Chapter 1 Wire/Cable Types

XLPE

PVC

20 mil or > (1)

230V 400/460V

15 mil

> 15.2 m (50 ft)

< 15.2 m (50 ft)

575V

Selecting Wire to Withstand Reflected Wave Voltage for New and Existing Wire Installations in

Conduit or Cable Trays

Conductor

Environment

Conductor Insulation

Insulation Thicknes s

DRY

(per NEC Article 100)

WET

(per NEC Article 100)

XLPE (XHHW-2)

Insulation for

< 600V AC

System No RWR or Ter mi na to r

Required

OK for < 600V AC

System

No RWR or

Terminator Required

Reflected Wave

Reducer?

RWR or

Ter m in a to r

No RWR or Ter m in a to r

RWR or

Ter mi na to r

No RWR or Ter mi na to r

Reflected Wave

Reducer?

Cable

Length

Number of

Drives in Same

Conduit or Wire

Tra y

15 mil PVC

in Not

Recommended.

Use XLPE

or > 20 mil

15 mil PVC

is Not

Recommended.

Use XLPE

or > 20 mil

Multiple Drives

in Single Conduit

or Wire Tray

Single Drive,

Single Conduit or

Wire Tray

See NEC Guidelines (Article 310 Adjustment Factors) for Maximum Conductor Derating and Maximum

Wires in Con duit or Tray

(1) The minimum wire size for PVC cable with 20 mil or greater insulation is 10 gauge.

IMPORTANT

Figure 1 - Wire Selection Flowchart

Temperature Rating

In general, follow these temperature ratings for installations:

• In surrounding air temperature of 50 °C (122 °F), use 90 °C (194 °F) wire (required for UL)

• In surrounding air temperature of 40 °C (104 °F), use 75 °C (167 °F) wire (required for UL)

Refer to the user manual of the drive for other restrictions.

The temperature rating of the wire affects the required gauge. Verify that your installation meets all applicable national, state, and local codes.

12 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Wire/ Cable Typ es Chapter 1

One Ground Conductor

Three Ground Conductors

Gauge

The correct wire size is determined by a number of factors. The user manual for each drive lists a minimum and maximum wire gauge based on the amperage rating of the drive and the physical limitations of the terminal blocks. Local or national electrical codes also set the required minimum gauge based on motor full load current (FLA). Follow both of these requirements.

Number of Conductors

Local or national electrical codes can determine the required number of conductors. Generally, these configurations are recommended:

• Figure 2

for drives up to and including 200 Hp (150 kW).

• Figure 3

for drives larger than 200 Hp (150 kW).

Space the ground conductors symmetrically around the power conductors. Verify that the ground conductors are rated for full drive ampacity.

shows cable with a single ground conductor that is recommended

shows cable with three ground conductors that is recommended

Figure 2 - Cable with One Ground Conductor

G BR

Figure 3 - Cable with Three Ground Conductors

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 13

Chapter 1 Wire/Cable Types

Unacceptable

Accepta ble

Insulation Thickness and Concentricity

Wire must have an insulation thickness of ≥ 15 mil (0.4 mm/0.015 in.). The wire insulation must not have significant variations of concentricity around the wire.

Figure 4 - Insulation Concentricity

Geometry

The physical relationship between individual conductors is important in drive installations.

Individual conductors in conduit or cable trays have no fixed relationship and are subject to cross coupling of noise, induced voltages, excess insulation stress, and other possible interference.

Fixed geometry cable (cable that keeps the spacing and orientation of the individual conductors constant) offers significant advantages over individual loose conductors, including reduced cross-coupling noise and insulation stress. Three types of fixed geometry, multi-conductor cables are discussed in this section. See Unshielded Cable on page 15

Armored Cable on page 17

Table 1 - Recommended Cable Design

Type Max Wire Size Where Used Rating/Type Description

Type 1 2 AWG Standard installations

100 Hp or less

Type 2 2 AWG Standard installations

100 Hp or less with brake conductors

Type 3 500 MCM AWG Standard installations

150 Hp or more

Type 4 500 MCM AWG Water, caustic chemical,

crush resistance

Type 5 500 MCM AWG 690V applications Tray-rated 2000V, 90 °C (194 °F) Three tinned copper conductors with XLPE insulation. Three bare copper

600V, 90 °C (194 °F) XHHW2/RHW-2

600V, 90 °C (194 °F) RHH/RHW-2

Tray-rated 600V, 90 °C (194 °F) RHH/RHW-2

Four tinned copper conductors with cross-linked polyethylene (XLPE) insulation

Four tinned copper conductors with XLPE insulation plus one shielded pair of brake conductors.

Three tinned copper conductors with XLPE insulation and three bare copper grounds and polyvinyl chloride (PVC) jacket.

Three bare copper conductors with XLPE insulation and three copper grounds on 10 AWG and smaller. Acceptable in Class I and II, Division I and II locations.

grounds and PVC jacket. IMPORTANT: If terminator network or output filter is used, connector

insulation must be XLPE, not PVC.

, Shielded Cable on page 16, and

14 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Wire/ Cable Typ es Chapter 1

Typ e 1 I nst al latio n, w ithout Brake Conductors

Single Ground Conduc tor

PVC Outer Sheath

Filler

Multiple Ground

Conducto rs

PVC Outer Sheath

Filler

Unshielded Cable

Properly designed multi-conductor cable can provide superior performance in wet applications, significantly reduce voltage stress on wire insulation, and reduce cross coupling between drives.

The use of cables without shielding is generally acceptable for installations where electrical noise created by the drive does not interfere with the operation of other devices, such as communication cards, photoelectric switches, weigh scales, and others. Verify that the installation does not require shielded cable to meet specific electromagnetic compatibility (EMC) standards for CE, C-Tick, or FCC requirements. Cable specifications depend on the installation type.

Type 1 and Type 2 Installation

Type 1 or Type 2 installations require 3-phase conductors and a fully rated individual ground conductor with or without brake leads. Refer to Table 1 on

page 14 for detailed information and specifications on these installations.

Figure 5 - Type 1 Unshielded Multi-conductor Cable without Brake Leads

Type 3 Installation

Type 3 installation requires three symmetrical ground conductors whose ampacity equals the phase conductor. Refer to Table 1 on page 14 information and specifications on this installation.

Figure 6 - Type 3 Unshielded Multi-Conductor Cable

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 15

for detailed

Chapter 1 Wire/Cable Types

Shield

Drain Wire

Chose the outer sheathing and other mechanical characteristics to suit the installation environment. Consider the surrounding air temperature, chemical environment, flexibility, and other factors in all installation types.

Shielded Cable

Shielded cable contains all of the general benefits of multi-conductor cable with the added benefit of a copper-braided shield that can contain much of the noise generated by a typical AC drive. Use shielded cable for installations with sensitive equipment, such as weigh scales, capacitive proximity switches, and other devices that can be affected by electrical noise in the distribution system. Applications with large numbers of drives in a single location, imposed EMC regulations, or a high degree of communication/networking, are also good candidates for shielded cable.

Shielded cable can also help reduce shaft voltage and induced bearing currents for some applications. In addition, the increased size of shielded cable can help extend the distance that the motor can be from the drive without the addition of motor protective devices, such as terminator networks. Refer to Chapter 5 information regarding reflected wave phenomena.

for

Consider all of the general specifications dictated by the environment of the installation, including temperature, flexibility, moisture characteristics, and chemical resistance. In addition, include a braided shield specified by the cable manufacturer as having coverage of at least 75%. An additional foil shield can greatly improve noise containment.

Type 1 Installation

An acceptable shielded cable for Type 1 installations has four XLPE insulated conductors with a 100% coverage foil and an 85% coverage copper braided shield (with drain wire) surrounded by a PVC jacket. For detailed specifications and information on Type 1 installations, refer to Table 1 on page 14

Figure 7 - Type 1 Installation — Shielded Cable with Four Conductors

16 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Wire/ Cable Typ es Chapter 1

Drain Wire for Brake

Conduc tor Shiel d

Shield for Brake

Condu ctors

TIP

Type 2 Installation

An acceptable shielded cable for Type 2 installations is essentially the same cable as Type 1, plus one shielded pair of brake conductors. For more information on Typ e 2 in sta llat io ns, re fe r to Table 1 on page 14

Figure 8 - Type 2 Installation — Shielded Cable with Brake Conductors

Type 3 Installation

These cables have 3 XLPE insulated copper conductors, 25% minimal overlap with helical copper tape, and three bare copper grounds in PVC jacket.

Other types of shielded cable are available, but the selection of these types can limit the allowable cable length. Particularly, some of the newer cables twist four conductors of THHN wire and wrap them tightly with a foil shield. This construction can greatly increase the cable charging current required and reduce the overall drive performance. Unless specified in the individual distance tables as tested with the drive, these cables are not recommended and their performance against the lead length limits supplied is not known. For more information about motor cable lead restrictions, refer to, Conduit on page 67

Moisture on page 72

, Effects On Wire Types on page 73, and Appendix A.

Armored Cable

Cable with continuous aluminum armor is often recommended in drive system applications or specific industries. Armored cable offers most of the advantages of standard shielded cable and also combines considerable mechanical strength and resistance to moisture. It can be installed in concealed and exposed manners and removes the requirement for conduit (electrical metallic tubing [EMT]) in the installation. It can also be directly buried or embedded in concrete.

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 17

Chapter 1 Wire/Cable Types

IMPORTANT

Cable with Three Ground Conductors

Cable with a Single Ground Conductor

Conduc tors wit h XLPE

Insulation

Optional Foil/Copper Tape

and/or Inner PVC Jacket

Armor

Optional PVC Outer Sheath

Because noise containment can be affected by incidental grounding of the armor to building steel when the cable is mounted, we recommend that the armored cable has an overall PVC jacket (see Chapter 2

Interlocked armor is acceptable for shorter cable runs, but continuous welded armor is preferred. General recommendations for ground conductors are listed here:

• Cable with a single ground conductor is sufficient for drive sizes up to and including 200 Hp (150 kW).

• Cable with three ground conductors is recommended for drive sizes larger than 200 Hp (150 kW).

Space the ground conductors symmetrically around the power conductors. Verify that the ground conductors are rated for full drive ampacity.

Figure 9 - Armored Cable with Three Ground Conductors

A good example of cable for Type 5 installation is Anixter 7V-5003-3G. This cable has three XLPE insulated copper conductors, 25% minimal overlap with the helical copper tape, and three bare copper grounds in PVC jacket.

If a terminator network or output filter is used, the connector insulation must be XLPE, and not PVC.

18 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Wire/ Cable Typ es Chapter 1

Stranded Neutral

PVC Outer Sheath

Filler

European Style Cable

Cable used in many installations in Europe must conform to Low Voltage Directive (LVD) 2006/95/EC. Generally recommended are flexible cables with a bend radius of 20 times the cable diameter for movable cable, and 6 times the cable diameter for fixed installations, with a screen (shield) of 70…85% coverage. Insulation for both conductors and the outer sheath is PVC.

The number and color of individual conductors can vary, but the recommendation is for three phase conductors (customer-preferred colors) and one ground conductor (green/yellow).

Ölflex Classic 100SY, or Ölflex Classic 110CY, are examples.

Figure 10 - European Style Multi-conductor Cable

Input Power Cables

In general, the selection of cable for AC input power to a drive has no special requirements. Some installations suggest shielded cable to prevent coupling of noise onto the cable (see Chapter 2

), and in some cases shielded cable can be required to meet noise standards, such as CE for Europe, C-Tick for Australia/ New Zealand, and others. This can be especially true if an input filter is required to meet a standard. The user manual for the drive has the requirements for meeting these types of standards. Additionally, individual industries can have required standards due to environment or experience.

For AC variable frequency drive applications that must satisfy EMC standards for CE, C-Tick, FCC, or others, we recommend the same type of shielded cable that is specified for the AC motors be used between the drive and transformer. Check the individual user manuals or system schematics for specific additional requirements to meet EMC standards.

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 19

Chapter 1 Wire/Cable Types

182.9 (600)

91.4 (300) 91.4 (300)

15.2 (50)

167.6 (550) 152.4 (500)

15.2 (50)15.2 (50)

All examples represent motor cable length of 182.9 m (600 ft)

IMPORTANT

Motor Cables

The majority of recommendations regarding drive cables are for issues caused by the nature of the drive output. A PWM drive creates AC motor current by sending DC voltage pulses to the motor in a specific pattern. These pulses affect the wire insulation and can be a source of electrical noise. Consider the rise time, amplitude, and frequency of these pulses when choosing a wire/cable type. Consider these factors when choosing a cable:

• The effects of the drive output once the cable is installed.

• The need for the cable to contain noise caused by the drive output.

• The amount of cable charging current available from the drive.

• Possible voltage drop (and subsequent loss of torque) for long wire runs.

Keep the motor cable lengths within the limits set in the user manual for the drive. Various issues, including cable charging current and reflected wave voltage stress, can exist. If the cable restriction is listed because of excessive coupling current, apply the methods to calculate total cable length, as shown in Figure 11 If the restriction is due to voltage reflection and motor protection, refer to

Appendix A

Figure 11 - Motor Cable Length for Capacitive Coupling

for exact distances allowed.

20 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

For multi-motor applications, review the installation carefully. Consult your distributor drive specialist or Rockwell Automation when considering a multi-motor application with greater than two motors. In general, most installations have no issues. However, high peak cable charging currents can cause drive over-currents or ground faults.

Wire/ Cable Typ es Chapter 1

Cable for Discrete Drive I/O

Analog Signal and Encoder Cable

Discrete I/O, such as start and stop commands, can be wired to the drive with a variety of cabling. We recommend shielded cable to reduce cross-coupled noise from power cables. Standard individual conductors that meet the general requirements for type, temperature, gauge, and applicable codes are acceptable if they are routed away from higher voltage cables to minimize noise coupling. However, multi-conductor cable can be less expensive to install. Separate control wires from power wires by at least 0.3 m (1 ft)

Table 2 - Recommended Control Wire for Digital I/O

(1)

Type

Unshielded Per US NEC or applicable national or local code – 300V, 60 °C

Shielded Multi-conductor shielded cable 0.750 mm

(1) The cable choices shown are for 2-channel (A and B) or 3-channel (A,B, and Z) encoders. If high resolution or other types of

feedback devices are used, choose a similar cable with the correct gauge and number of conductor pairs.

Wire Type(s) Description Minimum

3-conductor, shielded.

(18 AWG),

Insulation Rating

(140 °F)

Always use shielded cable with copper wire. We recommend wire with an insulation rating of 300V or greater. Separate analog signal wires from power wires by at least 0.3 m (1 ft). Run encoder cables in a separate conduit. If signal cables must cross power cables, cross at right angles. Terminate the shield of the shielded cable as recommended by the manufacturer of the encoder or analog signal device.

Table 3 - Recommended Signal Wire

Signal Type/ Where Used

Standard analog I/O – 0.750 mm2 (18 AWG), twisted pair, 100% shield

Remote pot – 0.750 mm2 (18 AWG), 3-conductor, shielded

Encoder/Pulse I/O < 30.5 m (100 ft)

Encoder/Pulse I/O

30.5…152.4 m (100…500 ft)

Encoder/Pulse I/O

152.4…259.1 m (500…850 ft)

(1) If the wires are short and contained within a cabinet that has no sensitive circuits, the use of shielded wire is not always necessary,

but is recommended.

Wire Type( s)

Combined 0.196 mm

Signal 0.196 mm2 (24 AWG), individually shielded

Power 0.750 mm

Combined 0.330 mm

Signal 0.196 mm2 (24 AWG), individually shielded

Power 0.750 mm

Combined 0.750 mm

Description Minimum

(1)

with drain

(24 AWG), individually shielded

(18 AWG)

or 0.500 mm

(18 AWG)

(18 AWG), individually shielded pair

Insulation Rating

300V, 75…90 °C (167…194 °F)

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 21

Chapter 1 Wire/Cable Types

Communication

This section provides cable recommendations for these communication protocols:

• DeviceNet on page 22

• ControlNet on page 23

• Ethernet on page 23

• Remote I/O and Data Highway Plus (DH+) on page 24

• Serial (RS-232 and RS-485) on page 24

DeviceNet

DeviceNet cable options, topology, distances allowed, and techniques are specific to the DeviceNet network. For more information, refer to DeviceNet Media Design and Installation Guide, publication DNET-UM072

In general, the four cable types for DeviceNet media meet these criteria:

• Round (thick) cable with an outside diameter of 12.2 mm (0.48 in.); normally used for trunk lines, but can also be used for drop lines.

• Round (thin) cable with an outside diameter of 6.9 mm (0.27 in.); normally used for drop lines, but can also be used for trunk lines.

• Flat cable, normally used for trunk lines.

• KwikLink drop cable, used only in KwikLink systems.

Round cable contains these five wires:

• One twisted pair (red and black) for 24V DC power.

• One twisted pair (blue and white) for signal.

• One drain wire (bare).

Flat cable contains these four wires:

• One pair (red and black) for 24V DC power.

• One pair (blue and white) for signal.

Drop cable for KwikLink is a 4-wire, unshielded, gray cable.

The distance between points, installation of terminating resistors, and chosen baud rate are significant to the installation. For more information, refer to the DeviceNet Media Design and Installation Guide, publication DNET-UM072

22 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Wire/ Cable Typ es Chapter 1

ControlNet

ControlNet cable options, topology, distances allowed, and techniques are specific to the ControlNet network. For more information, refer to the ControlNet Coax Media Planning and Installation Guide, publication

CNET-IN002

Depending on the environment at the installation site, there are several types of RG-6 quad shield cables that can be appropriate. The standard cable recommended is Allen-Bradley catalog number 1786-RG6, Quad Shield coax. Country, state, or local codes, such as the U.S. NEC, govern the installation.

Installation Environment Use this Cable Type

Light industrial • Standard PVC

Heavy ind ustrial • Lay-on armored

High/Low temperature or corrosive (harsh chemicals) • Plenum-FEP

Festooning or flexing • High flex

Moistu re: direct bu rial, with fl ooding compound, fungus resistant • Flood burial

• CM-CL2

• Light interlocking armor

• CMP-CL2P

The allowable length of segments and installation of terminating resistors play a significant part in the installation. Refer to the ControlNet Coax Media Planning and Installation Guide, publication CNET-IN002

, for details.

Ethernet

Ethernet communication interface wiring is very detailed for the type of cable, connectors, and routing. In general, Ethernet systems use shielded twisted pair (STP) cable, or unshielded twisted pair (UTP) cable, with RJ45 connectors that meet the IP67 standard and are appropriate for the environment. Use cables that meet Telecommunications Industry Association/Electronic Industries Alliance (TIA/EIA) standards at industrial temperatures.

Shielded cable is recommended when the installation can include welding, electrostatic processes, drives over 10 Hp, motor control centers (MCCs), high power RF radiation, or devices carrying current in excess of 100 A. Shield handling and single-point grounding, also discussed in this document, are also important for the proper operation of Ethernet installations.

There are also important distance and routing limitations published in detail.

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 23

Chapter 1 Wire/Cable Types

IMPORTANT

Remote I/O and Data Highway Plus (DH+)

Only Allen-Bradley catalog number 1770-CD shielded twinaxial cabling is tested and approved for remote I/O and DH+ installations.

The maximum cable length depends on the baud rate.

Baud Rate Maximum Cable Length

57.6 Kbps 3048 m (10,000 ft)

115.2 Kbps 1524 m (5000 ft)

230.4 Kbps 762 m (2500 ft)

All three connections (blue, shield, and clear) must be connected at each node.

Do not connect in a star topology. Only two cables can be connected at any wiring point. Use either series or daisy chain topology at all points.

Serial (RS-232 and RS-485)

Follow these recommended standard practices for serial communications wiring:

• One twisted pair and one signal common for RS-232.

• Two twisted pair, with each pair individually shielded, for RS-485.

24 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Chapter 2

Power Distribution

This chapter discusses different power distribution schemes and factors that can affect drive performance.

System Configurations

The type of transformer and the connection configuration feeding the drive have an important role in drive performance and safety. This section includes a brief description of some of the more common configurations and their qualities and shortcomings.

Delta/Wye with Grounded Wye Neutral

Delta/Wye wi th Grounde d Wye Neutr al is the most common type of distribution system. It provides a 30° phase shift. The grounded neutral provides a direct path for common mode current caused by the drive output (see

Chapter 3

Rockwell Automation recommends the use of grounded neutral systems for these reasons:

and Chapter 6).

• Controlled path for common mode noise current

• Consistent line-to-ground voltage reference that minimizes insulation

stress

• Accommodation for system surge protection schemes

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 25

Chapter 2 Power Distribution

Single-phase Loads

Three-phase

Loads

Delta/Delta with Grounded Leg, or Four-wire Connected Secondary Delta

Delta/Delta with Grounded Leg or Four-wire Connected Secondary Delta is a common configuration with no phase shift between input and output. The grounded center tap provides a direct path for common mode current caused by the drive output.

Three-phase Open Delta with Single-phase Center Tapped

Three-phase Open Delta with Single-phase Center Tapped is a configuration providing a Three-phase delta transformer with one side tapped. This tap (the neutral) is connected to earth. The configuration is called the antiphase grounded (neutral) system.

The open delta transformer connection is limited to 58% of the 240V, single-phase transformer rating. Closing the delta with a third single-phase, 240V transformer provides full rating for the two single-phase, 240V transformers.

The phase leg opposite the midpoint has an elevated voltage when compared to earth or neutral. The hottest high leg must be positively identified throughout the electrical system. Make the hottest high leg the center leg in any switch, motor control, three-phase panel board, and so on. The NEC requires orange color tape to identify this leg.

26 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

Power Distribution Chapter 2

Ungrounded Secondary

ATT EN TI ON : Grounding the transformer secondary is essential to the safety of

personnel and safe operation of the drive. Leaving the secondary floating causes dangerous high voltages between the chassis of the drive and the internal power structure components. Exceeding the voltage rating of the drive’s input metal oxide varistor (MOV) protection devices can cause a catastrophic failure. In all cases, the input power to the drive is referenced to ground.

If the system is ungrounded, other general precautions, such as a system level ground fault detector or system level line to ground suppressor, can be necessary. Or consider an isolation transformer with the secondary of the transformer grounded.

Refer to local codes regarding safety requirements. Also refer to Surge Protection

MOVs and Common Mode Capacitors on page 45.

High Resistance Ground

Grounding the Wye Secondary Neutral through a resistor is an acceptable method of grounding. Under a short circuit secondary condition, any of the output phases to ground do not exceed the normal line-to-line voltage. This is within the rating of the MOV input protection devices on the drive. The resistor is often used to detect ground current by monitoring the associated voltage drop. Because high frequency ground current can flow through this resistor, be sure to properly connect the drive motor leads by using the recommended cables and methods. In some cases, multiple drives (that can have one or more internal references to ground) on one transformer can produce a cumulative ground current that can trigger the ground fault interrupt circuit. Refer to Surge

Protection MOVs and Common Mode Capacitors on page 45.

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 27

Chapter 2 Power Distribution

PEN or N

IMPORTANT

TN-S Five-wire System

TN-S Five-wire distribution systems are common throughout Europe, with the exception of the United Kingdom and Germany. Leg-to-leg voltage (commonly at 400V) powers three-phase loads. Leg-to-neutral voltage (commonly at 230V) powers single-phase loads. Neutral is a current conducting wire, and connects through a circuit breaker. The fifth wire is a separate ground wire. There is a single connection between ground and neutral, typically in the distribution system. Do not make connections between ground and neutral within the system cabinets.

AC Line Voltage

AC Line Impedance

In general, all Allen-Bradley drives are tolerant to a wide range of AC line voltage. Check the individual specifications for the drives you are installing.

Incoming voltage imbalances >2% can cause large unequal currents in a drive. Use an input line reactor when line voltage imbalances are >2%.

To prevent excess current that can damage drives during events such as line disturbances or certain types of ground faults, provide a minimum amount of impedance in front of the drives. In many installations, this impedance comes from the supply transformer and the supply cables. In some cases, an additional transformer or reactor is recommended. If any of these conditions exist, consider adding impedance (line reactor or transformer) in front of the drive:

• Installation site has switched power factor correction capacitors.

• Installation site has lightning strikes or voltage spikes in excess of 6000V

peak.

• Installation site has power interruptions or voltage dips in excess of 200V AC.

• The transformer is too large in comparison to the drive. See impedance recommendations on Table 4 on page 30

through Table 13 on page 41.

Tab le s 4 through 13 define the largest transformer size for each product and rating based on specific differences in construction, and is the

28 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

preferred method to follow.

Power Distribution Chapter 2

% impedance is the nameplate impedance of the transformer. Typical values range from 0.03 (3%) to 0.06 (6%).

xfmr

line-line

)

* % Impedance

% impedance is the nameplate impedance of the transformer. Typical values range from 0.03 (3%) to 0.06 (6%).

Otherwise, use one of the following more conservative methods:

• For drives without built-in inductors – add line impedance whenever the transformer kVA is more than 10 times larger than the drive kVA, or the percent source impedance relative to each drive is less than 0.5%.

• For drives with built-in inductors – add line impedance whenever the transformer kVA is more than 20 times larger than the drive kVA, or the percent source impedance relative to each drive is less than 0.25%.

To identify drives with built-in inductors, see the product specific information in

Table 4 on page 30

through Table 13 on page 41. The shaded rows identify

products ratings without built-in inductors.

Use these equations to calculate the impedance of the drive and transformer:

Drive Impedance (in ohms)

drive

3 * I

line-line

input-rating

Transformer Impedance (in ohms)

line-line

xfmr

3 * I

* % Impedance

xfmr-rated

Transformer Impedance (in ohms)

line-line

xfmr

3 * I

* % Impedance

xfmr-rated

Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014 29

Chapter 2 Power Distribution

EXAMPLE

IMPORTANT

xfmr

drive

0.2304

102.6

= 0.00224 = 0.22%=

The drive is rated 1 Hp, 480V, 2.7A input. The supply transformer is rated 50,000 VA (50 kVA), 5% impedance.

line-line

3 * I

input-rating

)

line-line

* % Impedance =

drive

xfmr

480V

= = 102.6 Ohms

3 * 2.7

480

* 0.05 = 0.2304 Ohms

50,000

Note that the percent (%) impedance has to be in per unit (5% becomes 0.05) for the formula.

0.22% is less than 0.5%. Therefore, this transformer is too big for the drive. Consider adding a line reactor.

Grouping multiple drives on one reactor is acceptable; however, the reactor percent impedance must be large enough when evaluated for each drive separately, not evaluated for all loads connected at once.

These recommendations are advisory and do not address all situations. Site specific conditions must be considered to assure a quality installation.

Table 4 - AC Line Impedance Recommendations for Bulletin 160 Drives

Bulletin Number

160

(1) Shaded rows identify drive ratings without built-in inductors. (2) Maximum suggested KVA supply without consideration for additional inductance.

Drive Catalog Number

-AA02 240 0.37(0.5) 15 3R4-B 6.5 4

-AA03 240 0.55 (0.75) 20 3R4-A 3 4

-AA04 240 0.75 (1) 30 3R4-A 3 4

-AA08 240 1.5 (2) 50 3R8-A 1.5 8

-AA12 240 2.2 (3) 75 3R12-A 1.25 12

-AA18 240 3.7 (5) 100 3R18-A 0.8 18

-BA01 480 0.37(0.5) 15 3R2-B 20 2

-BA02 480 0.55 (0.75) 20 3R2-A 12 2

-BA03 480 0.75 (1) 30 3R2-A 12 2

-BA04 480 1.5 (2) 50 3R4-B 6.5 4

-BA06 480 2.2 (3) 75 3R8-B 3 8

-BA10 480 3.7 (5) 100 3R18-B 1.5 18

Volts kW (H p) Max Sup ply

(1)

kVA

(2)

3% Line Reactor Open Style 1321-

Reactor Inductance (mH)

Reactor Current Rating (amps)

30 Rockwell Automation Publication DRIVES-IN001M-EN-P - March 2014

+ 114 hidden pages