AEMT - Association of Electrical and Mechanical Trades

20 April 2021
Improving standards for sustainability of electric motors
Thomas Marks, Secretary, AEMT, looks at the importance of considering all the options when an electric motor needs to be repaired.
Image courtesy of Houghton International

Image courtesy of Houghton International

 The international focus on minimising our carbon footprint aims to reduce the effects of global warming and stabilize our weather patterns. At the same time, there is a realisation that we need to improve our sustainability and preserve the world’s resources for the next generation and beyond. For those operating in industrial sectors, there is an opportunity to contribute to these efforts by looking at the most effective solution for motor repairs.

Many service centres for electric motors belong to the Association of Electrical and Mechanical Trades (AEMT) which encourages members to assess and deliver the most appropriate repair or replacement of a motor. This ensures that their customers have the opportunity to reduce their energy usage by upgrading to a more efficient option, or repair the asset using the latest international standards and extend the service life of the motor cost-effectively.

Improved performance

Making the best choice relies on having all the relevant information for a certain situation. The decision to replace a motor with one of a higher efficiency classification is usually governed by the initial cost against the additional savings that will be made during its service life. Depending on the application, upgrading from an IE2 to an IE3 motor may not be justified by the improvements in efficiency.

However, some operators have concerns about the efficiency of a repaired motor compared to the original factory build specification. These questions can be answered by a recent study carried out jointly by the AEMT and the Electrical Apparatus Service Association (EASA) in the USA. It concluded that the energy efficiency of a motor is retained after a repair that follows international standards and guides of good practice.

Furthermore, the repair or remanufacturing of a motor effectively doubles the service life of the machine, especially in modern, clean environments. The reliability of the motor is similarly extended and in many cases they will carry the same warranty period as a new machine.

For those with specialist environments that require repairs to hazardous area motors, suitably qualified and certified repair centres will follow international standards (IEC 60079 19) to ensure the continued safety of the intrinsic protection concepts. It is worth noting that only suitably trained staff should undertake such repairs, otherwise the asset record for the motor may be compromised and with it, the assurances of the manufacturer’s design.

Circular economy

The decision to repair a motor, rather than replacing it, is not only a cost-effective solution, it also minimises the amount of resources that need to be used. This is summarised in IEC 60034 23, the international standard for rotating electrical machine: repair, overhaul and reclamation. It highlights the fact that replacing the bearings in a 110 kW machine effectively doubles the life of the asset while retaining 99% of the original machine. Furthermore, the old bearings can be recycled as high quality ‘green’ steel scrap.

For a refurbishment that involves a motor rewind, 90.5% of the motor is reused and those parts that are replaced consist mainly of high-grade copper and steel scrap that can be recycled. In fact, just 0.9% by weight of the original machine, made up of varnish, grease, insulation and paint, will not be reused or recycled.

In every case, maintenance and repair centres that are members of AEMT will always consider all the options for each case and ensure that the operator is aware of both the financial and environmental costs. With all the available information, it is the responsibility of those working with electric motors to decide on the best course of action.

More News from the AEMT
AEMT News
20 April 2021
Thomas Marks, Secretary, AEMT, looks at the importance of considering all the options when an electric motor needs to be repaired.
AEMT News
16 March 2021
The challenges of Covid-19 are affecting every business and where possible, some aspects have been transferred to an online setting. Professional training remains as important as ever and the AEMT has developed online courses that enable delegates to complete training on Ex-rated equipment to acquire or renew certification.
AEMT News
20 January 2021
Over the past 30-plus years, we have been made more aware of the impact of global warming and the consequences it has on our everyday lives. Corporations and individuals alike have a responsibility to reduce waste and strive to be more efficient with the resources we use. Improving the efficiency of electrical equipment reduces the demand on generation plants, allowing renewable sources to produce a greater proportion of the overall requirement. Thomas Marks, AEMT Secretary, looks at how the service and repair sector can help operators of electrical equipment to reduce running costs and their environmental impact at the same time.

Twitter Feed

News: Improving standards for sustainability of electric motors