ul 1446 standard of systems of insulating materials the ... · pdf fileslide 2 objectives...

© 2014 UL LLC.

UL 1446 Standard of Systems

of Insulating Materials – The

New 7th Edition

Mark Raymond

Principal Engineer

Visit us at Hall 2.1, Booth 21E41

www.coilwindingexpo.com/ berlin/ 20-22June 2017

Objectives

•What is an Electrical Insulation System

•A Brief History of Electrical Insulation Systems

•Why Revise UL 1446?

•UL 1446 7th Edition

•Future Plans for UL 1446

•Defined Life Thermal Aging of EIS

Insulation System Definition

Electrical Insulation System

(EIS) – Electrical insulating

structure containing one or

more electrical insulating

materials (EIM) together with

associated conducting parts

employed in an

electrotechnical device

Example - the combination

of an enameled magnet wire,

molded bobbin ground and

interwinding insulation, and

impregnating resin in a

transformer

Slide 3

EIS Components

Electrical Insulating Materials

(EIM) – Materials relied on in

the EIS to prevent risk of

electric shock and dielectric

breakdown (formerly known as

Major Components)

Non-electrical Insulating

Materials (NIM) – Materials

used for mechanical or thermal

applications and not relied on to

prevent electric shock or

dielectric breakdown (formerly

known as Minor Components)

Slide 4

History of Electrical Insulation Systems

Need to know

the effects of

Temperature

on Electrical

Insulation

US Navy ships

have limited space

and smaller equip-

ment was needed

to allow for more

room

But how will it

perform?

Compare new

materials with

existing known

service life

materials

1958 US Navy

sponsored

Round Robin

EIS testing

Establish

Thermal

aging test

procedure

to allow

comparison

Slide 5


Functional Evaluation of

Motorette Insulation

Systems - March 1959;

Brancato, Johnson,

Campbell & Walker

Reliability Prediction

Studies on Electrical

Insulation: Navy

Summary Report - July

1977; Brancato, Johnson,

Campbell & Walker

IEEE 117 - IEEE Standard

Test Procedure for

Evaluation of Systems of

Insulating Materials for

Random-Wound AC

Electrical Machinery

Military Specification

MIL-E-917D (Navy),

covering the basic

requirements of

electrical power

equipment for naval

shipboard use

Slide 6


A material that is classified as suitable for a

given temperature may be found suitable for

a different temperature, either higher or lower,

by an insulation system test procedure.

(para. 3.5.2.1.10)“

”

Slide 7


(1) “Material Thermal Class Ratings vs EIS Thermal Class Rating,” Eltek International Laboratories, April 2015.

Study(1) conducted

comparing EIM

ratings vs. EIS

thermal ratings

established by Full

Thermal Aging

Test data from 30 EIS Aging tests were reviewed

15 (50%) were rated higher than the lowest EIM rating

14 (47%) were rated lower than the lowest EIM rating

1 (3%) were rated the same as the lowest EIM rating

This study supports the value in thermal evaluation of an EIS as a complete

system rather than relying upon individual EIM ratings alone to determine

thermal class for the system

Slide 8

What is UL 1446?

Standard of

Insulating

Materials –

General

First Edition

of UL 1446

Published

June 1978

Makes Use of

Existing

Standards for

Evaluation of

EIS and EIM,

predominately

IEC standards

Provides

Guidance on

Substitution

of Materials

UL 1446

Slide 9

UL 1446 Standards Technical Panel (STP)

• Accredited Standards Developer

An organization that meets the ANSI Procedures for the

Development and Coordination of American National

Standards, and has been approved by the ANSI Executive

Standards Council (ExSC) for the development of American

National Standards.

• ANSI

The American National Standards Institute (ANSI) is a

private nonprofit organization that coordinates and

administers the U.S. voluntary standards and conformity

assessment system. ANSI also coordinates the U.S.

participation in the development of international standards.

Slide 10


Consist of members representing various

categories

• Authorities Having Jurisdiction (AHJ)

• Commercial/Industrial User

• Consumer

• General

• Government

• International Delegate

• Producer

• Supply Chain

• Testing & Standards

Slide 11


Slide 12

Updated: 2016/02/26


• UL has only 1 of the 22 votes

• The STP structure gives industry and other

interests strong influence in the standards

development process

Slide 13

Why Revise UL 1446 Standard?

• Scope was limiting

•Removed Reference to voltages

•Allows for expansion outside of low voltage and

consumer applications

• Test methods referenced

• US based ASTM Standards

• Add IEC methods as Primary reference

• Focus on internationally accepted test methods

Slide 14


Slide 15

• Confusing Terminology

• Motorette = General Purpose Model (GPM)

• Major Component = Electrical Insulating

Material (EIM)

• Minor Component = Non-electrical Insulating

Material (NIM)


• Difficult to find Requirements

• Reorganize the Structure of the Standard

• Needs Logical Progression

• Add Clarification

Slide 16

UL 1446 Standard Update

UL 1446 7th Edition

Published

November 11, 2016

Changes in 7th Edition:

• Reorganize the sections into a logical flow

sequence

• Retain sections 1-4 in same location with these

changes:

• Scope – revised to remove voltage limitation

• Addition of considerations for High Voltage

EIS

• IEC standards added and are preferred test

method

• Glossary updated for clarity

• Major = Electrical Insulating Material (EIM)

• Minor = Non-electrical Insulating Material

(NIM)Slide 17


Changes in 7th Edition:

•Section 5 - EIS Performance

Criteria

•Section 6 - Performance

tests: Full Thermal aging of

EIS – IEC 61857 (all parts)

Slide 18

UL 1446 7th Edition

Published

November 11, 2016


Slide 19

• Section SA Substitution and

modification to EIS guidelines

• SA4 - Magnet wire substitution

• SA5 - Varnish substitution

• SA6 - Ground and Interwinding

Insulation and Encapsulant

substitution

• SA7 –One temperature thermal

aging

• SA8 – Two temperature thermal

aging

• SA9 – Sealed Tube Chemical

Compatibility test

• SA10 – Infrared Analysis test

UL 1446 7th Edition

Published

November 11, 2016


Slide 20

• Section SB Magnet Wire and

Magnet Wire Coatings

• SB1-4 – Introduction, scope and

evaluation requirements

• SB5 – Magnet wire and coatings

performance tests

• Thermal aging

• Full (3 temperatures)

• 1 temperature

• Heat shock

• Dielectric

• IR analysis of chemistry

UL 1446 7th Edition

Published

November 11, 2016


Slide 21

• Section SC Varnishes and Impregnating

Resins

• SC1- Scope

• SC2 – Varnish requirements

• SC3 – Varnish Thermal Aging test

UL 1446 7th Edition

Published

November 11, 2016


Slide 22

• Appendix A – Information for Magnet

Wire Substitution

• Includes NEMA and IEC types

UL 1446 7th Edition

Published

November 11, 2016

UL 1446 Standard Update – Future Plans

Slide 23

• Adding requirements and test methods

for High Voltage insulation system

testing directly into UL 1446

• Currently HV requirements and tests

are certified by using other standards

• IEEE C57.12.60

• IEEE 1776

• IEC 60034-18-31

• Adding methods to UL 1446 will help all

parties understand what tests are

needed for all EIS type evaluations.

• Add requirements and guidance when

using IEC 61857-31 “Applications with

a designed life of 5000 h or less”

UL 1446 7th Edition

Published

November 11, 2016

New IEC Standard Issued in This Year

• IEC 61857-31 “Electrical insulation systems –

Procedures for thermal evaluation – Part 31:

Applications with a designed life of 5000 h or less”

was published on January 24, 2017

• The dilemma for manufacturer is having a product

with a design life far less than what is established for

a traditional full thermally aged EIS

• Why use costly materials that will meet higher

temperature ratings in a product that will never be

used for the life established by FTA testing?

• With limited life the ability to use less expensive

materials at higher temperatures is now feasible and

can be evaluated with an abbreviated thermal aging

program

24

What Is Meant By Design Life?

• For an EIS evaluation this is interpreted as

operational “on” time

• For example, if a household appliance

with a motor that is designed to only be

used for 30 minutes a day, that would

roughly be equal to 200 hours of use a

year or 2000 hours after 10 years

• The non-operational “off” time when the

appliance is not in use, is not included in

the EIS design life rating

Slide 25

Defined Life Thermal Aging (DLTA) Program

• Evaluate for a thermal endurance rating

• 130°C

• 155°C

• 180°C

• 200°C

• 220°C

• 240°C

• UL can review existing FTA data to determine if

a higher thermal rating can be issued with a

shorter life expectancy.

26

• Specific hour ratings that will be

issued:

•1,500 hrs

•2,500 hrs

•4,000 hrs

•5,000 hrsExample:

155ºC/2500h

DLTA Requirements

• Test program covered

under IEC 61857 Part 31:

“Applications with a

designed life less than

5000 hours”

• This test is carried out on

General Purpose Models

27

• Test Program follows the

same cycling as existing

UL 1446 FTA program

DLTA Requirements Two Paths

• Procedure A and B –

• 1-temperature aging

• Aging temperature to be 10 ºK

above design temperature

• Follow standard procedures, cycle

to be set at 168 hours

• Minimum 1500hr rating requirement

(Procedure A); Can be extended to

5000hrs (Procedure B)

• Life rating is equal to ageing time or

average life if failures occurred

• Procedure C –

• 2-temperature aging

• The aging temperatures for:

• the lower temperature shall be 20 to 30

ºK above the expected thermal class

value and

• the higher ageing temperature shall be

30 to 35 ºK above the expected thermal

class value

• Can be used for up to 5000 hours

(1500 hr minimum still applies)

• Use the ageing test time results from

both ageing temperatures and plot

them as a linear expression and

intercept at the desired thermal

rating to determine life hours

28

DLTA Benefits

• Provide an alternative investigation path for end-product manufactures

interested in certifying magnetics for short-term life expectancies.

• Ability to evaluate a new electrical insulation system in a shorter time

frame (3-4 months vs. 12+ months)

• Ability to evaluate less costly materials for higher temperature

conditions

• Ability to get a higher thermal rating for existing full thermally aged EIS

• higher temperatures means smaller device means lower costs

• Ability to certify new EIS for less cost and sample preparation

• Ability to use short term Chemical Compatibility Test to add non-

electrical insulating materials (NIM)

• Industry accepted global IEC Test Method

29

© 2014 UL LLC.

Thank You!

Any Questions?

UL 1446 Standard Of Systems

of Insulating Materials – The

New 7th Edition

www.coilwindingexpo.com/ berlin/ 20-22June 2017

Visit us at Hall 2.1, Booth 21E41

ul 1446 standard of systems of insulating materials the ... · pdf fileslide 2 objectives...

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