Electric Motor maintenance: Market Overview, Common Errors, Future Sensors
Electric motors are the basic inherent part of industrial production as
well as of home appliances, HVAC (Heating, Ventilation, and Air Conditioning),
motor vehicles, and other applications. The use of electric motors is expected
to grow significantly in the next years. The annual growth of the use of
electric motors in new and already penetrated sectors creates pressure on their
effectiveness and new functionalities (e.g. IoT integration, Smart
The lack of efficiency and new functionalities present themself in different
forms of errors, that take place in the individual motors depending on their
usage, surroundings, installation, in one word – the maintenance
Electric motor maintenance: Common causes, available practices
Let’s look into multiple groups of main issues with electric motors and
identify possible solutions to achieve effective maintenance.
As for any mechanical device, it is natural for an electric motor to be
exposed to a range of issues causing malfunctions. Due to the importance of
electric motors, especially in industrial, mobility, and even consumer
products – their malfunctions or failures cause negative affect the whole
process of a company or a product, thus the customer is pressured to implement
reactive solutions, which, frankly speaking, is not the most economically viable
Reacting to an already-occurred obstacle, one does not have enough time to
make the most efficient decision. The user has to rather quickly replace or fix
the failed motor (reactive maintenance). This nor increases the potential
competitive advantage neither terminates the fact that the motor will
malfunction again because this motor will need to be used with the same
workload, in order to bring the same results.
Companies lose millions every day because of the unpredicted failure of
electric motors. On a large scale, the swift reaction of replacing
malfunctioning motors with the same ones, or just fixing them, eventually slows
down the development of the industry as such (slow automation, slow growth of
large companies, naturally slows regional development in the sector).
Taking a step back, and looking at the Motor Failures is a simple way to
eventually identify a set of decisions that would serve as proper
solutions with solid ROI.
Let’s look into multiple groups of main issues with the motors and
identify possible solutions.
First and foremost, the bearings are fundamental parts of the functioning of
an electric motor. Even in case of failure of one of the bearings, a chain of
negative effects can accrue such as overheating, lubrication issues, and
There are numerous causes of bearing fatigue or any other bearing issues,
some of the most common ones are excessive load management, misfits,
misalignment, etc. According to experts, up to 13 % of motor failures accrue due to bearing
Vibrations as such take place for various reasons, other than bearing-related
ones, such as
misalignment/inbalance in the application where the motor is used;
the shafts getting out of line (i.e. out of supposed parallel
wear and tear of the components (ball or roller bearings, drive belts or
gears, gear tooth that is heavily chipped).
Knowledge of early-stage vibration anomalies in the motor (bearing damage
will cause uncontrolled, immoderate vibrations within the motor) is a huge
competitive advantage for making the motor lifetime longer. The faster these
vibration anomalies are detected – the easier it is to conduct maintenance
An electric motor is essentially a device that turns electric input into
mechanical energy. This process naturally generates heat during operation. It is
a standard process and usually, some heat emission is natural, it should not
cause any alarm. However, excessive overheating can occur and even cause damage
in addition to deterioration of the components that are housed within the motor
itself. The most common reason being operational overload.
When a motor is being used in higher pressure conditions than it is designed
for, overheating may occur. Even a few degrees of additional heat within the
motor can be enough to wear out some of the essential components (i.e.
To deliver the designed output mechanical energy, a certain electrical power
needs to be inputted into the motor. Should this power exceed the designed
amount, the motor accordingly exceeds its limits, naturally placing risks of
malfunction. These are often called voltage spikes (a.k.a. power surge).
High-frequency AC volts as such may compromise the motor
effectivity and the whole basic performance as such. Harmonics are essentially
electric voltages/currents that can raise a significant drawback for the
electrical system as the motor cannot use extra energy effectively. The system
is unbalanced, the extra energy reflects on the windings and bearings, causing
energy losses, and finally a decrease in a motor lifetime.
Reduce harmonic distortion by installing a variable frequency drive, or you
can try using a filter to help keep harmonic distortion damage to a minimum.
Harsh, unfitting physical environment
Restricted Ventilation: Covering the motor’s enclosure
can result in the motor overheating.
Improper Lubrication: Not only can this result in damaged
bearings but can also throw grease into windings.
Moisture: Condensation can cause rust within an
Vibration, Belt Tension, and Misalignment: All three can
shorten the life of a motor if not corrected.
High Ambient Temperatures: Consider derating to a lower
power load if your motr temperature goes above its specified limits, or, install
a motor designed with proper insulation for operation at higher ambient
Condemnation: Condemnation is a usual cause of failure for
electric motors, especially for the bearings. It may appear when foreign
substances work their way into cleaning solutions or bearing lubricants. Dust,
dirt, abrasive materials, and small particles of metal, such as steel, can find
their way into the electric motor from other machinery(or directly from the
motor as a result of wear and rear), contaminated tools, or if the motor is
handled by technicians with dirty hands. Denting in the raceways and rolling
elements and vibrations indicate motor bearing failure due to
Electric Motor Sensing system: Future is tiny
The motors are usually able to reach certain operational heights to carry out
especially demanding tasks, however, these are not designed to be used at those
operational pressures at all times. This surely compromises the
performance and decreases the lifetime of a motor.
After a long back and forth the industry is naturally claiming that the key
to keeping the electric motor applications running smoothly, and getting the
maximum capacity for the longest time possible is to practice long-term
preventive and predictive maintenance. Surely there are various solutions (per
each above-mentioned issue), however, we try to introduce one that helps make
the electric motors safer, more efficient, and overall – intelligent, with
just one system.
This solution lies in the MicroWire, a
miniaturized sensor of physical quantities that can provide data about the
physical environment of the motor, directly from within!
This data (electric current, temperature, vibrations, pressure) is gathered
in real-time, and due to the miniaturized size of the MicroWire sensor –
there are minimum or no additional design changes needed to gather real-time
information about the motor directly from the local environment of interest
(i.e. MicroWire can be attached to the bearings and provide real-time data of
Vibrations, Pressure, Temperature etc.).
Market research within the Machine Learning and Artificial Intelligence
industries states that the time, finances and the final quality of these –
first and foremost depend on the precision and appropriate quantity of the data.
The form of the data gathered via RVmagnetics MicroWire sensors is up to the
customer. It can be adjusted to the software in place, as the system can gather
data with up to 10.000×/sec frequency, with extremely high precision.
Considering the accuracy of the MicroWire sensors – we essentially make it
clear the roadmap to Motor Maintenance, not only to maximize
efficiency and lifetime of the system but also to ensure the
safety of the environment where the motor is used.
There is an obvious benefit in motor efficiency for the businesses that use
electric motors in some form of their applications, but what is not less
important to mention is the environmental, global impact that a more efficient
electric motor can have. Electric motors emit a total of 6,800 metric tons of
carbon dioxide in a year. A transition to energy-efficient motor systems would
reduce the global electricity demand for electric motors by around 20% to 30%
By using more efficient motors, countries can save 300 TWh per year of
electricity in 2030, saving 200 Mt of CO2 emissions—equivalent to the annual
electricity generated by approximately 60 coal-fired power plants with a
capacity of 1,000 MW.