Regardless of the application, you and your team need to depend on your electric motor to operate consistently. Not all industrial applications are the same, but you can determine which motor will be best suited for your job by using this checklist. Consider these six factors when selecting your next industrial motor:

1. Size and Power

2. Reliability

3. Durability

4. Cost-Effectiveness

5. Precision

6. Safety

By understanding these characteristics and why they are required, you can select a motor that will offer cost-effective performance over its full-service lifetime. From food processing to chemical manufacturing, this checklist applies.

1. Size and Power

Industrial applications often require large, powerful motors capable of delivering high productivity over many hours. In these conditions, an electric motor that isn’t adequately sized will quickly deteriorate and wear out, causing downtime and loss of productivity while incurring a replacement cost.

When choosing an industrial motor, confirm it’s rated for the power required during the most intensive part of its operation, typically during acceleration and peak load times. If the required speed is lower than the motor’s base speed, a gearbox solution allows for a smaller, more cost-effective motor operating at a higher efficiency.

Industrial motors' duty cycle can be very high, especially when they’re the primary component in an operation. Ensure the rated duty cycle of the motor can be operated for its condition, or the motor will experience overheating and shorter service life.

2. Reliability

Industrial motors are often utilized in high-use applications that depend on consistent performance and productivity. By selecting industrial motors that are reliable and require minimal maintenance, plants can save on unplanned maintenance costs.

The use of brushes in the commutator of a motor can become problematic in these conditions, as the brushes quickly wear down and require periodic replacement that causes significant downtime. Because of this, brushed DC motors can be less reliable and potentially unsuited to high duty-cycle operations. As an alternative, AC induction motors have a simpler, brushless, low-maintenance design that is well suited for intensive industrial use.

Please look at our AC & DC Motor Speed Control to learn about the difference in controls for both motors.

If a motor requires regular maintenance, ensure it’s easy to dismount to reduce the downtime of the application.

3. Durability

Motor environments often contain pollutants such as moisture, dust, oil, and corrosive chemicals. To maintain performance, the motor must be able to operate effectively in this environment without becoming damaged.

The crucial factor in a motor's durability is its enclosure, which protects the vulnerable windings from encountering harmful pollutants. Open Drip-Proof (ODP) motors should only be used in clean, dry climate-controlled environments, as they provide little protection against airborne contaminants. For highly polluted environments, Totally Enclosed Fan Cooled (TEFC) motors are a great option, as they prevent the free exchange of air from the interior to the exterior motor body. Washdown duty motors use TEFC enclosure to protect the motor from regular washing.

To gauge whether an enclosure provides enough protection, its IP (Ingress Protection) rating should match or exceed the conditions that the motor is subjected to.

4. Cost-Effectiveness

In many motor applications, the cost of the motor is not the only consideration. Depending on the job, the costs may include the electric motor, gearbox (if required), and any other peripherals such as speed control, which are required for the motor to perform its function.

The AC induction motor is the most cost-effective solution for medium to large applications that do not require precise speed control. If a speed control is required, consider incorporating this as part of your project budget and timeline, as speed controls can be complex to set-up with AC motors. For medium to large applications, the speed controller pricing is usually offset by the savings on the cost of the motor.

DC motors are relatively expensive for their complex designs in medium to large applications. Speed control is simpler compared to AC motors, especially for smaller applications. They can effectively compete in terms of the total cost of the motor solution.

5. Precision

Many industrial applications such as robotics, actuation, and manufacturing automation require a different kind of motor solution that performs complex tasks consistently at high precision. The two main types of motors used in these applications are stepper motors and servo motors.

Stepper motors rotate a fixed amount known as a ‘step,’ providing holding torque when that step is reached. This makes them ideal for situations where the motor will rotate a specified amount and then come to a stop, such as in manufacturing and machine tools applications.

Servo motors are motor packages with precise speed and torque control capable of precise complex-motion performance. DC motors can be effectively controlled over a wide speed range with a simple circuit, as they dominated the servo motor industry for many years. However, improved AC motor speed controllers, such as Vector Control drives, have made it possible for cost-effective AC motors to provide servo-like precision and holding torque. They are a great option for medium to large applications.

6. Safety

Depending on your industry, a higher level of safety may be required for the motor environment.

In the chemical and petroleum industry, where the atmosphere is volatile, an explosion-proof motor may be required by law. These motors can contain an internal explosion of a specified substance without igniting the surrounding atmosphere, providing much-needed protection to personnel and infrastructure in the vicinity.

In food manufacture and processing, minimizing the risk of pathogens is a high priority. All the equipment, including motors, need to be regularly washed down and thoroughly cleaned. A fully enclosed washdown-duty motor would be ideal for this environment, with the physical exterior using approved paint or a paint-free stainless-steel body.

Check out our Electric Motor Safetyarticle for additional tips on maintaining motor safety.

Summary

Industrial motors often face exceptionally tough operating conditions, and downtime can be very costly for the operating company and those dependent on the productivity of the application. When selecting an industrial motor, it is important to prioritize the key characteristics required for the conditions that it will operate in to ensure it provides long-lasting performance.