Distribution Transformers

From 1 October 2004, distribution transformers manufactured in or imported into Australia must comply with Minimum Energy Performance (MEPS) requirements which are set out in AS 2374.1.2-2003.

The scope of transformer MEPS covers oil-immersed and dry-type distribution transformers with power ratings from 10 kVA to 2500 kVA intended to be used on 11 kV and 22 kV networks.

The intention of MEPS is to increase energy efficiency by eliminating low efficiency transformers from the market and to encourage the use of high efficiency transformers.

The standard also defines minimum efficiency levels for “High Power Efficiency Transformers”. Only products which meet the specified efficiency levels can apply this term to promotional or advertising materials.

Transformers within the scope of MEPS are required to have on their rating plate a statement that indicates compliance with AS 2374.1.2.

The MEPS for distribution transformers are set out as power efficiency levels at 50% of rated load in AS 2374.1.2 when tested in accordance with AS 2374.1 or AS 2735, as applicable.

How to register for MEPS

You will find information on how to register for MEPS on the Registration page.

Which products does MEPS not apply to?

MEPS does not apply to the following types of transformers:

• Transformers other than those on 11 or 22 kV networks
• Instrument transformers
• Auto transformers
• Traction transformers mounted on rolling stock
• Starting transformers
• Testing transformers
• Welding transformers
• Three phase transformers with three or more windings per phase
• Arc-furnace transformers
• Earthing transformers
• Rectifier or converter transformers
• Uninterruptible power supply (ups) transformers
• Transformers with an impedance less than 3% or more than 8%
• Voltage regulating transformers
• Transformers designed for frequencies other than 50 hertz
• Gas filled dry type transformers
• Flameproof transformers

Regulatory standards and test procedures for distribution transformers are published by Standards Australia. The standards that apply are:

• AS 2374.1.2: Power Transformers Part 1.2: Minimum Energy Performance Standard (MEPS) requirements for distribution transformers
• AS 2374.1: Power transformers Part 1: General
• AS 2735: Dry-type power transformers

These standards can be purchased from SAI Global under licence from Standards Australia.

AS 2374.1: Power transformers Part 1: General

Abstract:
Specifies the technical requirements for single and three-phase power transformers, including auto transformers, but excludes single-phase transformers rated at less than 1 kVA, three-phase transformers rated at less than 5 kVA, and certain special transformers such as instrument, starting, testing and welding transformers, transformers for static converters and those mounted on rolling stock. Based on but not equivalent to and has been reproduced from IEC 60076-1:1993. Includes Australian variations such as commonly used power ratings and preferred methods of cooling, connections in general use, and details regarding connection designation.

Scope:
This part of International Standard IEC 60076 applies to three-phase and single-phase power transformers (including auto-transformers) with the exception of certain categories of small and special transformers such as: single-phase transformers with rated power less than 1 kVA and three-phase transformers less than 5 kVA; instrument transformers; transformers for static convertors; traction transformers mounted on rolling stock; starting transformers; testing transformers; welding transformers. When IEC standards do not exist for such categories of transformers, this part of IEC 60076 may still be applicable either as a whole or in part. For those categories of power transformers and reactors which have their own IEC standards, this part is applicable only to the extent in which it is specifically called up by cross-reference in the other standard. At several places in this part it is specified or recommended that an agreement shall be reached concerning alternative or additional technical solutions or procedures. Such agreement is to be made between the manufacturer and the purchaser. The matters should preferably be raised at an early stage and the agreements included in the contract specification.

AS 2735: Dry-type power transformers

Abstract:
Specifies requirements for dry-type power transformers (including autotransformers) having highest voltage for equipment values up to and including 36 kV. This Standard should be read in conjunction with AS 2374, Power transformers. Where Australian Standards do not exist for other particular power transformers, this Standard may be applicable as a whole or in parts.

Scope:
This standard specifies requirements for dry-type power transformers (including auto-transformers) having highest voltage for equipment values up to and including 36 kV.

The following small and special dry-type transformers are not covered by this standard:

(a) Single-phase transformers rated at less than 1 kV.A and polyphase transformers rated at less than 5 kV.A.

(b) Instrument transformers (covered by AS 1243 and AS 1675).

(c) Transformers for semiconductor converters (AS 1955).

(d) Starting transformers.

(e) Testing transformers.

(f) Traction transformers mounted on rolling stock.

(g) Flameproof transformers.

(h) Welding transformers.

(j) Voltage regulating transformers.

(k) Small power transformers in which safety is a special consideration.

Where Australian standards do not exist for the transformers mentioned above or for other special transformers, this standard may be applicable as a whole or in parts.

MEPS Levels

MEPS levels set out as minimum power efficiency levels at 50% of rated load for various transformer types, are outlined below. Reference should be made to AS 2374.1.2-2003 for detailed conditions and test method.

NOTE: Negotiations are currently underway for a proposed increase in the stringency of all MEPS levels. 

MINIMUM POWER EFFICIENCY LEVELS FOR OIL-IMMERSED TRANSFORMERS