IEE Colloauium on “lnsulatina Fluids”

Mike Morris Castrol UK Ltd. ELECTRICAL OIL - STANDARDS AND SPECIFICATIONS

Introduction

A first look at the title of this presentation might well prompt the question what is the

difference between a Standard and a Specification?. I thought it worthwhile,

therefore, to clarify this at the outset. The two words are frequently used

synominously but there are distinct differences between them particularly in an

International context.

By way of analogy consider the brands “Castrol” & ’Rolls Royce”. These two brands

immediately conjure up in ones mind standards of quality, performance, reliability all

leading to one hopes peace of mind. What the brands do not do is define in a

quantitative way what the standards mean. In order to do this we have to be specific

about what we are wishing to describe when thinking of eg “quality ‘ I . Thus we may

be thinking of the paint work of a Rolls Royce. We can then define a “specification”

for the paint eg colour is white, metallic high gloss, scratch resistant etc. or in the

case of a Castrol transformer oil we may be thinking of electrical properties &we can

then define them by eg breakdown voltage.

Thus we arrive at a definition of a STANDARD as a collection of criteria which

combined define the quality of a product, process, service or technique. The

quantification of specific criteria within the standard, imposing limits for acceptable

performance is the SPECIFICATION.

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Standard Funtions

Standards provide the following important functions :

Ensure uniformity of quality across National boundaries and thereby

promote international trade. Promote quality and fitness for purpose.

Promote clear communication between interested parties in a form suitable

for quotation. Promote the economic use of materials, energy and human resources in

the manufacture of goods, e.g. BS 5750. Promote health and safety and the protection of the environment, e.g. BS

7750 and Standards covering some Consumer goods. Voluntary agreed by public consultation both for National and International

Standards.

There are a number of different Standards organisations of which the following are

from a European viewpoint arguably the most important:

IS0 International Organisation for Standardisation

IEC International Electrotechnical Commission

CEN European Committee for Standardisation

CENELEC European Committee for Electrotechnical Standardisation.

In addition to these international organisations there are the national Standards bodies of which in the electrical industry the following are ones are most notable:

BSI UK

ASTM I ANSI USA

DIN Germany

USE OF BRITISH STANDARDS

The use of a BS is not mandatory and indeed their use is specifically excluded from

the requirement for registration with the Director General of Fair Trading. They can

therefore only be used with the consensus of interested parties.

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The BSI has a special “Duty of Care” as the publisher of authoritative national

documents. It is however the responsibility of the users to ensure that a particular

standard is appropriate to their needs. The Standards may become legally binding if

invoked as a part of a contract. Some BS are drafted in an advisory form, e.g. BS

5730 Code of Practice for Maintenance of Insulating Oil. Simple reference to these types of Standards in contracts is insufficient to covert their provisions into

contractual requirements.

It is important that in any reference to a Standard, the issue date is included or the

reference wording precludes the use of old editions.

Standardisation

The production of Standards is time consuming involving lengthy processes which

are defined by the governing bodies of the respective organisations. As an example if

we look at the production of an IEC Standard the various steps involved are as

follows:

BSI GEL/ 10

IEC TC10

Committee Draft (CD) I

Committee Draft (CDV) I

Final Draft International Standard ( FDIS)

Agreement ‘by CENELEC

International Standard (IS) becomes an European Norm (EN) I

Harmonisation by European National Committees

EN becomes an HD - National Standards Withdrawn I I

Looking at the mechanism by which BS are produced, referring particularly to

Electrotechnical Fluids. Electrotechnical Fluids are handled through the BSI Electrical

Department, of which there are four major segments. The particular segment

involved for Electrical Oil is the General Electrical Engineering segment, and the

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specific committee in that segment is GEUIO, of which the writer is Chairman and

the Secretariat is a member of the BSI staff. The committee is made up of

representatives from trade organisations, professional institutions and government

bodies.

As with all Standards their quality is dependent on the amount and quality of

information that goes into generating the Standard.lt is important that if there are

concerns regarding Electrotechnical Standards, they are communicated into GEUlO

via the writer, Secretariat or any member of the committee. This equally applies to

the revision of Standards which take place every 5 years. As a part of the Standards

procedure, all BSI drafts are open to public comment through the committee.

Specifications

GEUIO is responsible for some 44 Standards encompassing both liquids, gases and

the associated testing procedures.As this is an Oil Seminar, the relevant Standards of concern are BS 148/98 and IEC 296/82. These two Standards are very similar but I would highlight the major differences

between the specifications as follows:

The other major Electrical Oil Standards that you may come across are:

DIN 57370 Part 1 (VDE 0370 Part 1) German

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ASTM D3487 American

UK mineral electrical oils are refined from naphthenic crudes specifically to comply

with our own BS 148 requirements. It cannot be assumed that they comply with the

DIN 57370 & IEC 296 requirements & vice versa. Testing should always be carried

out to verify the specific specification requirement.

The major areas of concern when considering ASTM D3487 oils for suitability in a

BSI48 application would be with regard to oxidation stability and the presence of

oxidation inhihbitors which will be present even in uninhibited D3487 oils.

Health 8 Safety I Environment

Finally a mention of environmental and health & safety standards which are now of

importance from both a standardisation and a working perspective. The major ones

that are of importance from a standardisation viewpoint are :

IEC 51 - Guidelines for the inclusion of safety aspects in product standards IEC guide 109 - Environmental aspects - Inclusion in electrotechnical product

standards.

IS0 guide 64 - Guide for the inclusion of environmental aspects in product standards.

These standards are available as guides to what should now be considered when

writing international standards.They give guidance on the format for including in

standards the identification of Cautionary and Warning statements which arise from

carrying out a risk assessment on a standard.

From an environmental viewpoint materials used in or referred to in standards must

be designed for the environment ie suitable for recycling I reuse. Every consideration

must be given to the prevention of pollution which includes packaging, transportation,

use and disposal. All these points are covered in what is now being referred to as

Life Cycle Analysis (LCA) which embraces the cradle to grave concept of

environmental management.

0 1999 The Instiition of ETectical Engineers. Printed and published by the IEE, Savoy Place London WC2R 0% UK.

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