Four reasons why electric motors overheat

Increases in the temperature of an electric motor reduce its lifespan. By knowing the reason why electric motors overheat, users can develop a preventive maintenance strategy to combat inefficiencies.

11/03/2017


Photo by Manki Kim on UnsplashMany problems occur with electric motors. Including those associated with lubrication and voltage spikes. Also, over time, excessive heat occurs. Increases in the temperature of an electric motor reduce its lifespan. The winding insulation deteriorates, and the bearings may also deteriorate.

Why Motors Overheat

There are many reasons electric motors overheat. There are four primary reasons why overheating occurs:

1. Overload

The standard current tests most load levels, but overvoltage may still be an issue. Reducing the current may not entirely reduce excessive heat. It is best to know the operating capacity of your motors. Maintaining that level helps keep excessive heat to a minimum.

2. Starting and stopping

Limiting how often the motor starts and stops reduce its heat. Keep a close eye on the number of times it starts. If necessary, cut it down. Online motor testing is the easiest way to monitor the starting and stopping of the machine.

3. Poor power conditions

Power conditions often result in overheating. Poor power is associated with the use of VFDs, although the VFD may not be the primary cause of the problem.

4. Operating conditions

Operating electric motors in poor environmental conditions also leads to excessive heat. Associated problems include clogged ducts and high ambient temperature.

How to help motors keep their cool

One way to keep your motors cool is by reducing the excessive load that the motor handles. When considering the specifications of the task involved, match the appropriate motor to the necessary load.

Testing

Testing the motor as part of a routine maintenance program also reduces the possibility of failure due to excessive heat. Don’t judge the temperature of the motor just by feeling the outside surface with your hand. Touch, in general isn’t an excellent sensor; what feels hot to you is cool for somebody else.

Maintenance programs

That isn’t to say don’t worry about how hot the motor feels. Use the appropriate testing methods to find hot spots within the motor windings. Those accessive hot spots reduce the motor’s lifespan.

Ensure that your motors have the proper protection in place. That protection includes thermostats and overload protectors. One piece of a good maintenance plan, these devices ensure that the motor is not operating at damaging temperatures.

Electrical motors are often some of the most expensive assets in your facility. With proper maintenance and common sense, extending their useful lifespan becomes a little easier.

David Manney is marketing administrator at L&S Electric. This article originally appeared on Watts New, L&S Electric's blog. L&S Electric is a CFE Media content partner.



Top Plant
The Top Plant program honors outstanding manufacturing facilities in North America.
Product of the Year
The Product of the Year program recognizes products newly released in the manufacturing industries.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
June 2018
2018 Lubrication Guide, Motor and maintenance management, Control system migration
May 2018
Electrical standards, robots and Lean manufacturing, and how an aluminum packaging plant is helping community growth.
April 2018
2017 Product of the Year winners, retrofitting a press, IMTS and Hannover Messe preview, natural refrigerants, testing steam traps
June 2018
Machine learning, produced water benefits, programming cavity pumps
April 2018
ROVs, rigs, and the real time; wellsite valve manifolds; AI on a chip; analytics use for pipelines
February 2018
Focus on power systems, process safety, electrical and power systems, edge computing in the oil & gas industry
Spring 2018
Burners for heat-treating furnaces, CHP, dryers, gas humidification, and more
April 2018
Implementing a DCS, stepper motors, intelligent motion control, remote monitoring of irrigation systems
February 2018
Setting internal automation standards

Annual Salary Survey

After two years of economic concerns, manufacturing leaders once again have homed in on the single biggest issue facing their operations:

It's the workers—or more specifically, the lack of workers.

The 2017 Plant Engineering Salary Survey looks at not just what plant managers make, but what they think. As they look across their plants today, plant managers say they don’t have the operational depth to take on the new technologies and new challenges of global manufacturing.

Read more: 2017 Salary Survey

The Maintenance and Reliability Coach's blog
Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
One Voice for Manufacturing
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Maintenance and Reliability Professionals Blog
The Society for Maintenance and Reliability Professionals an organization devoted...
Machine Safety
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
Research Analyst Blog
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Marshall on Maintenance
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
Lachance on CMMS
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
Electrical Safety Update
This digital report explains how plant engineers need to take greater care when it comes to electrical safety incidents on the plant floor.
Maintenance & Safety
The maintenance journey has been a long, slow trek for most manufacturers and has gone from preventive maintenance to predictive maintenance.
IIoT: Machines, Equipment, & Asset Management
Articles in this digital report highlight technologies that enable Industrial Internet of Things, IIoT-related products and strategies.
Randy Steele
Maintenance Manager; California Oils Corp.
Matthew J. Woo, PE, RCDD, LEED AP BD+C
Associate, Electrical Engineering; Wood Harbinger
Randy Oliver
Control Systems Engineer; Robert Bosch Corp.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me