44 ELECTRIC MOTORS www.ipesearch.com
FEATURE
Improving the sustainability
of electric motors
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 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 thus 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 usually involves weighing
up 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 with 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, it 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 replace it, is not only a cost-effective
solution but also minimises
the 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.
Thomas Marks is secretary of the
AEMT
For more information:
www.theaemt.com
Tel: 01904 674899
Some
operators have
concerns
about the
efficiency of a
repaired motor
compared with
the original
factory-build
specification
With the realisation that we need to improve
sustainability and preserve the
world’s resources, those operating in
industrial sectors can contribute by
opting for the most effective solution for
motor repairs. Thomas Marks looks at the
importance of considering all the options
when an electric motor needs to be repaired
IMAGE COURTESY HOUGHTON INTERNATIONAL
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/www.theaemt.com
