Power Cord Types Explained: Standards, Cable Construction, and Applications

A power cord is the physical link that connects an electrical appliance to a power source, enabling the safe transmission of AC current.

In this guide, we will categorize power cords into three key dimensions: Regional Standards, Cable Construction, and Special Application Scenarios. Whether you are specifying cords for industrial machinery or high-density data centers, understanding these specifications is critical for safety and compliance.

Power Cord Types by Regional Standards

Power cords are designed according to regional electrical standards to ensure safety and compatibility. The most widely recognized standards include NEMA (North America), IEC (International), and several key Regional Standards such as CEE and BS.

International Standard: IEC 60320

The IEC standard, developed by the International Electrotechnical Commission (IEC), is widely adopted across the globe. The most common IEC power connectors comply with the IEC 60320 standard, which categorizes connector types using "C" codes. Connectors are classified as male or female depending on their mating type. Female connectors are assigned odd numbers, while their compatible male counterparts are assigned the next even number.

The following table presents common IEC power cord types along with their corresponding current, voltage, and temperature ratings, helping users quickly identify and select the appropriate power cord.

Below are the most commonly used power connector types in data centers:

C13/C14: These are among the most widely used IEC connectors, rated for 10A at 250V. They provide standard power connections for desktops, monitors, switches, routers, and other IT and network equipment. C13/C14 connectors are widely used in commercial office environments, enterprise IT rooms, and data center infrastructures.

C15/C16: Also rated for 10A at 250V, but capable of withstanding temperatures up to 120°C, these connectors are ideal for use in applications requiring higher heat tolerance, such as electric kettles and certain networking equipment.

C19/C20: Rated for 16A at 250V, these connectors are designed for high-power devices such as servers and data center equipment.

North American Standard: NEMA

The National Electrical Manufacturers Association (NEMA) defines standards for power connectors widely used across North America, compatible with 120 V and 240 V electrical systems in the U.S. and Canada. Among these connectors, the NEMA 5-15 is the most common. It has three prongs—hot, neutral, and ground—that are designed to provide safety and reliable operation.

Note:

The NEMA 5-15 is the standard plug in Canada, the United States, Mexico, and Panama.

It is also used throughout Central America, the Caribbean, and northern South America, including Colombia, Ecuador, Venezuela, and, as a legacy, parts of Brazil.

In addition, it is used in Japan, Taiwan, the Philippines, and Saudi Arabia.

The NEMA 5-15P to 5-15R power cord is the most common type, widely used in homes, offices, and small businesses. Other common configurations, such as NEMA 5-15P to C13 and NEMA 5-15P to C15, are typically used to power servers, networking equipment, and other IT devices, especially in small racks or lower-power data center applications.

Europe Standard: CEE 7/7

CEE connectors follow European CEE standards, which are set by CENELEC. The CEE 7/7 plug has become the standard in practice across many European countries, as it works with both Schuko (CEE 7/4) and French (CEE 7/5) sockets. The most common power cords with a CEE 7/7 plug are CEE 7/7 to C13, CEE 7/7 to C15, and CEE 7/7 to C19, widely used in IT and office settings to power computers, servers, networking equipment, and other electronic devices.

Other Regional Standards

In addition to the widely recognized IEC, NEMA, and CEE standards, many countries have developed their own regional power plug standard.

For example, Australia follows AS/NZS 3112 (Type I), Brazil uses NBR 14136, the UK adopts BS 1363 (Type G), and Japan follows JIS C 8303 (Type A and B). Despite these regional differences, many of these plugs continue to use the IEC 60320 standard for appliance connectors, ensuring compatibility across a wide range of devices.

Country

Plug Standard

Image

Denmark	AFSNIT 107-2-D1
United Kingdom	BS1363
Australia and New Zealand	AS/NZS 3112
China	GB1002
	GB2099
Japan	JIS C 8303
South Korea	KS C 8305
South Africa	SANS 164 (BS 546)
Argentina	IRAM 2073
Brazil	NBR 6147
	NBR 14136

Power Cord Types by Cable Construction

When selecting the appropriate type of power cord, two key factors should be considered: how the equipment will be used and the environment in which it will operate. Different applications impose different performance requirements on the cord, which typically determine the choice of jacket material and construction rating.

In practice, the most straightforward and reliable way to identify a power cord is to check the letter codes printed on its jacket. These codes serve as the cord’s “identity tag,” clearly indicating its voltage rating, material composition, and suitability for specific environments such as oil resistance, outdoor use, or high-flex applications.

The following table summarizes common UL letter codes and their characteristics, providing a quick reference for cord selection.

Type	Jacket Material	Key Properties	Typical Applications
SVT	PVC	Lightweight, flexible, 300V rated; indoor dry locations only	Office IT equipment, monitors, low-power network devices
SJT	PVC	Junior hard service; thicker jacket than SVT; 300V rated	Commercial IT equipment, network devices, entry-level racks
SJTW	PVC	Moisture and weather-resistant; suitable for damp locations	IT equipment in semi-humid rooms, edge data rooms
SJTOW	PVC	Oil-resistant and weather-resistant; durable jacket	Rack PDUs, servers, switches, UPS systems
ST	PVC	Hard service cord; heavy-duty; 600V rated	High-power equipment, infrastructure power
STOW	PVC	Oil- and weather-resistant; 600V rated	Industrial-grade power distribution, facility equipment
SO	Thermoset Rubber	Extra hard service; oil-resistant; high mechanical strength	Industrial power equipment, hospital facilities
SOOW	Thermoset Rubber	Oil-resistant insulation and jacket; weather-resistant; highly flexible	Mission-critical facilities, outdoor or mobile power
SEOW	TPE	Extra hard service; oil- and weather-resistant; flexible	High-end infrastructure, special environment deployments
SJEOW	TPE	Hard service; weather-resistant; flexible TPE jacket	Commercial and medical-grade equipment

Note:

Definitions of cable designations are derived from UL's designation scheme as defined in the National Electric Code (NEC)—NFPA-70.

Power Cord Types by Special Application Scenarios

Data Centers & Server Rooms

In high-density data centers and server rooms, Locking power cords are the preferred choice. Locking IEC cords and retention devices secure connections to rack PDUs and equipment, preventing accidental disconnects and ensuring continuous operation of servers, switches and core network infrastructure. In these environments, connection reliability, compatibility with standardized rack power management, and support for high continuous loads are far more important than generic IEC/NEMA cords.

Industrial Environments

For factories, workshops and other harsh industrial environments, specify industrial-grade heavy-duty power cords. These cables feature rugged construction (enhanced strain relief, abrasion- and oil-resistant jackets, high-temperature ratings and vibration tolerance), larger conductor gauges for higher ampacity, and robust connector designs that withstand mechanical stress. Choosing industrial-grade cords reduces failure rates, minimizes maintenance, and preserves uptime where equipment is exposed to chemicals, heat and continuous mechanical wear.

Medical environments

In hospitals, clinics and laboratories, use hospital-grade power cords that prioritize patient and equipment safety. Medical cords provide enhanced insulation, low leakage current, dedicated protective grounding and meet stringent medical safety standards; they are often paired with hospital-grade plugs/connectors and retention solutions. These characteristics ensure safe, reliable power delivery to monitors, diagnostic instruments and life-support systems while reducing the risk of electrical faults or interruptions.

Power Cord Types FAQ

Q: Can one power cord type be used worldwide?

A: No single power cord is universally compatible because wall plug standards and voltages vary by country. While IEC 60320 connectors are standardized for the device-end globally, the wall plug must still match the specific regional socket to ensure safe and legal operation.

Q: Which standards must hospital-grade power cords comply with?

A: Hospital-grade power cords must meet rigorous requirements for grounding reliability and durability. According to UL and CSA regulations, they must comply with the following specific standards:

Medical Equipment:

UL 60601-1 and CAN/CSA C22.2 No. 21.

Power Supply Cords:

UL 817 and CAN/CSA C22.2 No. 21.

Plugs and Receptacles:

UL 498 and CAN/CSA C22.2 No. 42.

Q: How do I choose the correct power cord for servers and network equipment?

A: The correct power cord is determined by the equipment's inlet type, current rating, and thermal requirements. Factors such as rack density, PDU outlet type, and operating temperature should also be considered to ensure safe and reliable operation.

Q: Why is "VW-1" printed on my power cord?

A: This marking indicates the flame-retardant rating of the cable. VW-1 means the cord has passed the UL Vertical Wire Flame Test, demonstrating strong self-extinguishing properties and reduced flame propagation along the cable in the event of a fire.

Q: How can I quickly identify the jacket material of a power cord?

A: Check the letter codes printed on the cable jacket:

If the code includes "

T

", the jacket is made of

PVC (thermoplastic)

.

If the code includes "

E

", it indicates

TPE (thermoplastic elastomer)

.

Cables without

T

or

E

(such as

SOOW

) typically use

thermoset rubber

, which provides higher resistance to abrasion and heat for industrial or outdoor use.

Conclusion

Understanding power cord types is essential for safety, compliance, and optimal equipment performance. This article explains power cords by regional standards, cable construction, and special application scenarios, providing guidance for selecting the correct cord for equipment. For proper selection and reliable operation, consult the complete Power Cord Buying Guide or explore FS Power Cords.