Power cords, also referred to as power cables, mains cables, or line cords, are essential components that supply power from an electrical outlet to an electronic device. They serve as the final step in delivering electricity that enables devices to turn on and operate.
This article will provide an in-depth explainer covering the purpose, design, types, standards, and proper use of power cords. It aims to help readers understand which cord powers their computer and how to choose the right one.
What is the Purpose of a Power Cord?
A power cord is a detachable cable that connects an appliance or electronic device to a power source, allowing the safe flow of electrical current to enable operation. Its key purpose is power transmission rather than data transfer.
Power cords have connectors on each end that plug into an outlet and the device. Common types of connectors include C13, C14, C15, C19, and C20. The cord’s gauge wire then carries electricity from the source to the equipment.
Key Components and Design
While acting as a crucial conduit for electricity flow, power cords also provide protective insulation and regulation. This well-designed cable contains:
- Copper wires to conduct current along the cord’s length. More wires enable increased capacity and efficiency.
- Insulating materials like PVC plastic to cover the wires, preventing electric shocks and fires.
- Safety certification markings to indicate testing and compliance with regulations. Common ones are UL, CSA, CE, TUV, and ETL.
Cords also tend to be thick and durable to withstand wear over time. Those with higher wattage ratings feature thicker internal wiring suited to increased loads.
What Are the Different Types of Power Cords?
There are a few common types of power cords used to power various devices:
IEC Power Cords
The most widely used power cords for computers, monitors, printers, and other electronic equipment are IEC power cords. These feature standardized IEC connectors and are interchangeable between compatible devices.
Popular IEC power cord types include:
- C13 cords – Feature a C13 connector to plug into a computer PSU and a C14 socket to plug into an outlet. Rated for 10A, 250V.
- C5 connectors – “Mickey Mouse” shaped, commonly used for laptops up to 3A.
- C7 connectors – Compact, figure-8 shape used for smaller devices up to 2.5A.
- C15 cords – Larger version of C13 rated for up to 16A. Used for monitors, printers, servers.
NEMA Power Cords
NEMA power cords have standardized NEMA connectors used in regions like North America and parts of Asia.
The most common NEMA cords are:
- 5-15 plug – Standard 15A, 125V straight blade plug used in North America.
- 5-20 plug – 20A, 125V straight blade plug used for higher power devices.
- 6-15 plug – 15A, 250V straight blade plug for devices needing higher voltage.
Specialty Power Cords
There are also various specialty power cords designed for specific devices:
- Appliance cords – Feature molded connectors to safely power kitchen, garage, and home appliances.
- Extension cords – Allow positioning appliances and devices further from outlets.
- International cords – Support localized power sockets, voltages, and plug shapes used abroad.
Power Cord Standards and Specifications
To ensure safety and compatibility, power cords are built to meet certain government and industry standards.
Wattage and Amperage Ratings
Cords have established wattage (W) and amperage (A) limits stated on their jackets. These determine the maximum power they can safely and efficiently transmit without overheating or deteriorating over time.
- Common ratings are 10A, 13A, 15A, 16A, 20A indicating capacities.
- C13, C5, and C7 cords are often 10A-13A; C14 and C15 cords are 15A+ rated.
Quality and Safety Certifications
Power cords meeting quality benchmarks and safety testing carry certifications like:
- UL – Indicates testing for fire/electrical safety in the US and Canada.
- ETL – Independent testing for quality and safety in North America.
- CE – European standard assessing health, safety, and environmental compliance.
- RoHS – Restriction of Hazardous Substances directive.
Government and International Standards
There are also various standards that regulate power cord design:
- IEC 60320 – International standard for connectors, plugs, and appliance couplers. Includes C13, C14, C15, C19, C20.
- NEMA standards – US standards regulating plug and receptacle configurations.
Which Power Cord Do I Use to Power My Computer?
- Most standard desktop computers use a C13 power cord connected to the PSU to receive power. The C14 plug connects to the wall outlet.
- Laptops typically use smaller C5 power cords also known as figure-8 connectors, or compact C7 cords.
- High performance computers may use C15 cords or C19 server PSU cords to supply added power capacity.
Matching your computer power socket shape, voltage, and amperage rating ensures a safe, reliable power supply.
I hope this guide has helped explain what power cords are used for and how to determine which one powers your computer! Let me know if you have any other questions.