The 2019 Rewind Study
The Effect of Repair/Rewinding on Premium Efficiency/IE3 Motors
Published: January 2021
In response to various opinions about the feasibility of maintaining motor efficiency during repair, including replacement of the stator winding, the Electrical Apparatus Service Association (EASA) and the Association of Electrical and Mechanical Trades (AEMT) conducted two comprehensive rewind studies using third-party testing laboratories. This study was a follow up to a similar study conducted 2003. This valuable publication explains the findings:
The 2019 study reaffirms the results of the 2003 study.
Motors can be repaired without reducing efficiency.
Good Practice Guide To Maintain Motor Efficiency
Published: January 2021
The original 2003 rewind study good practice guide has been editorially updated, with no substantive changes to any of the good practices. Intended primarily for service center personnel, the guide which is now an independent document and not part of the complete EASA/AEMT rewind study report, outlines the good practice repair methods used to achieve the results given in both studies. It contains repair tips, relevant motor terminology, and information about sources of losses in induction motors that affect efficiency.
ANSI/EASA AR100-2020: Recommended Practice for the Repair of Rotating Electrical Apparatus
Published: September 2020
ANSI/EASA AR100 “Recommended Practice for the Repair of Rotating Electrical Apparatus”is a must-have guide to the repair of rotating electrical machines. Its purpose is to establish recommended practices in each step of the rotating electrical apparatus rewinding and rebuilding processes.
The scope of this document describes record keeping, tests, analysis and general guidelines for the repair of induction, synchronous and direct current rotating electrical apparatus. It is not intended to take the place of the customer's or the machine manufacturer's specific instructions or specifications or specific accepted and applicable industry standards or recommended practices.
ANSI recognizes only one standard on a topic; therefore, the EASA Recommended Practice is the standard for repair of rotating electrical apparatus.
EASA AR200-2021: Guide For The Repair Of Dry-Type Transformers
Published: August 2021
This updated guide outlines best practices for the repair of dry-type transformers.
The previous version of AR200 (published in 2011) was titled Guide For The Repair Of Power And Distribution Transformers. Like preceding versions, it embraced a broad scope of transformer repair that included liquid-filled distribution or power transformers up to 10 MVA and 69 kV.
In preparing this update, the Technical Services Committee chose to narrow the scope to the types of transformer repair activities usually found in EASA service centers (i.e., non-liquid-filled distribution dry-type transformers with high voltage windings up to 69 kV and rated less than 15,000 kVA). After all, liquid-filled transformer repair and service is a specialty few members offer, with many standards and best practices differing from those for dry-type transformers.
EASA Technical Manual
The EASA Technical Manual, EASA's most comprehensive technical document, pulls from the knowledge and experience of EASA's technical support staff, members and industry leaders. At more than 900 pages, leverage this resource for your service center technicians, either on your computer or on your bookshelf.
The EASA Technical Manual is available FREE to members as downloadable PDFs of the entire manual or individual sections. Printed copies are available for sale.
Revised September 2022
Internal Connection Diagrams for Three-Phase Electric Motors
Published : April 2021
EASA members can download a PDF of Internal Connection Diagrams for FREE. Use the link below for the free PDF.
This edition of EASA Internal Connection Diagrams contains significantly more connections than the previous version (1982), as well as improved templates for drawing connection diagrams. It provides internal connection diagrams for three-phase windings. It can be used with either concentric or lap windings. It also covers all possible parallels; wye and delta, 2 - 48 poles; part windings; two-speed windings; wye-delta and consequent-pole connections, 2 - 48 poles. It includes PAM connections, as well as triple- and quadruple-rated connections.
Getting The Most From Your Electric Motors
This 40-page booklet provides great advice for obtaining the longest, most efficient and cost-effective operation from general and definite purpose electric motors.
This booklet covers topics such as:
- Installation, startup and baseline information
- Operational monitoring and maintenance
- Motor and baseline installation data
- How to read a motor nameplate
- Motor storage recommendations
Failures in Three-Phase Stator Windings
The life of a three-phase stator winding can be shortened dramatically when the motor is exposed to unfavorable operating conditions — electrical, mechanical or environmental. The winding failures shown are typical of what can happen is such circumstances. You can also order copies of the brochure detailing these failures.