When electric motors and motor controls are measured, two standards are used to do so – one is the National Electrical Manufacturers Association (NEMA) and the International Electrotechnical Commission (IEC). The former is used in North America and the latter in most parts of the world. The motors of both NEMA and IEC have the same output power, efficiency, and size. But then they do have differences between them and today, in this article, you will come to know about the differences between NEMA to c14 to NEMA 5 15r power cords and IEC power cords.
NEMA and IEC Power Cords – The Differences
NEMA and IEC are both electromechanical products, but today’s world demands flexibility among these two products to adapt to the market demands and local needs. But to adequately make use of this flexibility, you first must understand the major differences between NEMA and IEC, and here are they-
i) Philosophically Different
The philosophy, as maintained by NEMA, places special emphasis on developing resilient designs that can be used for a variety of purposes. Application range and easy selection are the two pillars on which this philosophy is based. NEMA motor control devices’ design has been made based on the NEMA Industrial Control Standard or ICS-2.
It involves a higher degree of knowledge like the duty cycle, motor load, and full load functions to understand the functionality of the IEC devices. It is because of these factors that the Original Equipment Manufacturer sector benefits from the IEC power cords more.
ii) Need for Training
Here lies one of the biggest differences between the IEC and the NEMA products. IEC products are application-specific and require a relatively high degree of knowledge to make them function properly. You needn’t have intensive training to select an IEC product, but to operate it, you need specific knowledge.
iii) The Market Division
There has been a huge market shift from IEC products to NEMA products as the commercial and light industries have shown a great liking for the IEC products and they have almost transitioned to this product. However, the processing industry has remained with the NEMA-style devices. If you add up the number of IEC products sold, then it outsells the NEMA-style ones, but in dollar valuation, NEMA-style devices outsell IEC products.
Key Differences Between NEMA and IEC
- The fundamental difference between them lies in the fact that NEMA provides for around 25% service factor in contrast to the IEC which focuses on space and cost-savings.
- Devices operating below 100A or 50HP are considered much bigger for NEMA and are costlier. Here IEC is strongly inclined towards power rating, which makes it more critical than the NEMA ratings. It is for this reason that the IEC system is not as popular as NEMA in the United States.
- While constructing the electrical elements, NEMA is the first choice as it is more inclined towards the design requirements whereas IEC concentrates on the IP ratings more.
- IEC doesn’t address corrosion as NEMA does. NEMA also provides a certain amount of protection against corrosion. The ratings of the two also differ as they protect different aspects.
- The IEC-rated equipment is cheaper than that of the NEMA-rated ones.
- NEMA ratings have versatility and are designed to support various applications.
- Large-sized devices, marketed in North America only, use NEMA power cord only whereas IEC ratings are for the more compact devices in the global market.
- IEC ratings are best for countering overloads while NEMA ratings are best for countering short circuits.
- IEC devices are safer than NEMA devices because they require safety covers.
The Common Misconception
This misconception is related to the NEMA starter as it looks larger than the IEC starter and people often feel that the starter is much more hardy and powerful than the IEC one. The fact is that the NEMA starter looks bigger just because of the design and nothing else. This way chances arise where the ratings go down for the IEC power cord as the classification used for it goes wrong. As a result, the IEC system is blamed in general as it fails to perform according to its rating standards. What happens in reality is different. According to the Underwriters Laboratory’s testing for both IEC and NEMA applications, the differences between them are not limited just to their sizes or cost-effectiveness, but also to the way the system works in actuality.
The ratings of a NEMA starter depend greatly on the highest horsepower ratings given to it by the National Electrical Manufacturers Association ISCS2 standard. The selection of the starters depends on the NEMA size which ranges from Size 00 to Size 9 and can be used on a wide range of applications. These applications range from simple on-and-off applications to the more demanding plugging and jogging applications. If you wish to select a NEMA motor starter then definitely watch out for the motor’s voltage and horsepower.
With the publication of the IEC 60947, the International Electrotechnical Commission, or IEC has clearly outlined the operational and performance characteristics of its devices. Having done that, it has not made anything specific regarding any standard size. The duty cycle of IEC devices is typically governed by utilization categories. As far as general motor starting applications are concerned, AC3 and AC4 are the commonest utilization categories for general motor IEC devices.
The mechanical, electrical, and industrial applications should undergo safety testing before their market release. The Ingress Protection mark is different from rating company to company, but the two primary outstanding standards are the NEMA and the IEC The NEMA 5 15r power cord.
It is very much needed that you gain in-depth knowledge regarding the ratings of NEMA and IEC before choosing between them. There isn’t any gross difference between the ratings of the two because of the efforts made by the industry to standardize it. The ratings have made it possible to remove the vague areas like the ‘waterproof’ one. It is always advisable that you check the ratings of NEMA and IEC before making the selection as it is the ratings that help you to understand what to and not to expect from the device. It is much more vital before going for the differences between the two.