What is the difference between NEMA motors and IEC motors, and which one is more energy-efficient?

Since 1926, the National Electrical Manufacturers Association (NEMA) has set standards for motors used in North America. NEMA regularly updates and publishes MG 1, a book that helps users correctly select and apply motors and generators.

It contains practical information on performance, efficiency, safety, testing, manufacturing, and the manufacturing of alternating current (AC) and direct current (DC) motors and generators.

The International Electrotechnical Commission (IEC) sets standards for motors in other parts of the world. Similar to NEMA, the IEC publishes standard 60034-1, which serves as a global market guide for motors.

Do you know the difference between the metric system, the imperial system, NEMA standards, and IEC standards? In China, the motor standards use IEC (European standards), while NEMA MG1 is the American standard.

Essentially, they are quite similar, but there are some differences in certain aspects. NEMA standards and IEC standards differ in terms of motor power utilization factor and rotor temperature rise. The power utilization factor for NEMA motors is 1.15, while for IEC (China),

it is 1. The way other parameters are labeled may also differ, but the actual content is essentially the same. Let's take a look below:

1. In terms of appearance, metric motors are more beautiful, in line with Eastern aesthetics, but there are more varieties of patterns in imperial motors.

NEMA STANDARD MOTOR

IEC standard motor

2. different contrasts

Overall, the main difference lies in the significant variation in mechanical dimensions and stricter sealing requirements according to IEC. In terms of electrical aspects, NEMA electrical requirements include a long-term overload factor of 1.15 and commonly seen high insulation requirements according to UL.

Comparison of NEMA and IEC motor frame sizes:

Although NEMA and IEC have many similarities, there are almost no fundamental differences between the two motor standards. NEMA emphasizes a more robust design for wider applicability. The breadth of ease of selection and application are two fundamental pillars of its design philosophy.

On the other hand, IEC focuses on application and performance. Choosing IEC equipment requires a higher level of application knowledge, including motor loads, duty cycles, and full load current (FLC) - used when selecting IEC contactors. In addition, NEMA designs have components with a safety factor, with service factors that can be as high as 25%, while IEC focuses on saving space and cost.

How is NEMA?

NEMA has not yet provided defined standards for IE5 in the North American market, although some manufacturers are selling motor drives for VFD drives, referred to as "ultra-high efficiency". The same concept also applies to achieving equivalent efficiency levels of IE5 through variable speed drives at full load and partial load. Integrated motor drives using ferrite-assisted synchronous reluctance technology are another solution that can provide IE5-level efficiency and simplify setup, while eliminating expensive wiring and installation time.

Why is energy efficiency a hot topic?

There are many reasons for the government's authorization of motors. Motors and motor systems account for approximately 53% of global electricity consumption. Motors can be used for 20 years or longer, so the energy consumed by inefficient motors accumulates over the product's lifespan, putting unnecessary pressure on the power grid and leading to avoidable CO2 emissions. By focusing on selecting the best motors, OEMs can design their equipment to improve overall system efficiency, thereby reducing environmental impact and saving costs, and ultimately delivering products to customers. In addition to reducing greenhouse gas emissions and energy costs, efficient motors can also improve air quality, reduce equipment downtime, and increase output for end users.

Is it worth upgrading? Savings and returns

The purchase price of motors and drives is only a few percentage points different compared to the energy consumption over the lifespan of the operating equipment. For low-voltage motors, the payback period for replacement is typically 2-3 years. When considering new investments, the typical payback period for IE efficiency levels is less than one year.

If you are purchasing the IEC standard motor, please contact with professional electric motor manufacturer - Dongchun motor , all motors warranty : 2 years.