Power Cords: Connection Types And Regulatory Issues Explained

1. Power Cords: Connection Types And Regulatory Issues Explained     A power cord is an essential element for all the cord connected electrical                           devices. It powers up your devices. Generally, power cords are connected in                         two ways.  1. Non-Detachable: It consists of a plug, the cordage, and a strain relief                         device. It is used to secure the cord to equipment enclosure.  2. Detachable: It is also known as power cord set. It consists of a plug,                             cordage, and a connector or receptacle.  Although when it comes to regulatory approvals, these cables are little                       tricky to understand. Let’s go through the brief of power cords which are                           intended for use in ITE and consumer products applications.    1​​

2. Before we begin, it would be good to note that power supply cords typically                             have two to three wires. ‘line’, ‘neutral’ and ‘ground’. Here are the standard                           IEC 60446 approved color codes:  1. In North America, the line wire is black, while it is either brown or grey                               elsewhere.  2. In North America, the neutral wire is white colored, while elsewhere it                         is blue colored.  3. In North America, the ground wire is green, while at all other places,                           it’s green with yellow stripes.  When you look for the buying options, it is important to ensure that the                             electrical rating of the power cord is higher than your equipment rating.                         Because an under-rated power cord may harm your system, cause                     overheating and an electrical fire. In general cases, your plug would need at                           least 125% of the rated current for the equipment. In North America, power                           cords designed to use with ITE equipment are rated as 125Vac/10A.  Here’s the break down about the power cords and their components:  Non-Detachable Power Cords  These power cords are hard-wired to the equipment. In general cases, you                         don’t need to remove the cord from the equipment.  To attach the stripped end of a non-detachable power cord there is a                           lug/ring terminal. One end of the terminal consists of a metallic ring or a                             2​

3. loop that is attached to a power terminal post. The other end is generally                             crimped on the stripped power cord wire. One more important thing to                         remember is, when utilizing this form of terminal, the crimp tool should be                           standard.  Manufacturers who own large equipment and need to ship power supplies                       occasionally might have chances that power supply cords get damaged                     during shipping. In such scenario, U.S recognized NRTLs (Nationally                   Recognized Testing Laboratories) allow the shipment under the following                   conditions:  ● Why the power cord needs to be disassembled.  ● The assembly of the disassembled equipment must be executed by                     qualified service personnel.  ● Detailed assembly instructions must be provided that address all                   aspects of the reassembly, including the connection of the main                     earthing terminals.  ● Instructions that state that no replacement cord would be used other                       than the one shipped with the product.  ● A suitable method of securing the power cord to the enclosure is                         provided, such as a strain relief grommet.  Detachable Cord  It is also known as a line cord, main cord, or power cable. It consists of a                                   flexible cord with electrical connectors male and female. The male end is                         attached to a molded electrical plug. The female consists of a molded                         3​

4. electrical receptacle. This connection method is meant to prevent an                     exposed live prong or pin that could cause an electric shock. The male plug                             connects to the electrical source, while the female connector attaches to                       the piece of equipment. Overcurrent protection fuse is another component                     of the cord.  That’s pretty much it about the power cords connection types. But it’s a                           vital part to understand the plug and cordage certifications and                     specifications based on their connection types. In North America, the                     NEMA 5 family of plugs is the most common type used. The NEMA 5 plug                               typically has a male plug featuring two flat blades. For example, you can                           consider buying NEMA 5-15 to C13 power cords as they meet all the                           industry standards. It does not have a current rating higher than 20 amps.                           For high-rated current, a ​NEMA Power Cords featuring the NEMA L14-30P                       plug and the NEMA L14-30P is rated at 30 amps.  Considering Cordage specifications, in North America, most commonly                 used cables are SVT, SJT, SJTW, ST, SPT-1, and SOW. While in Europe,                           cables must have approval and carry the “◄HAR►” mark on them.  Final Findings  We can clearly state that each country has their own standards of                         approvals. Considering the North American developing standards, NEMA                 (National Electrical Manufacturer Association) certify and declare the                 approved cords as NEMA Power Cords. These cables are typically used for                         ITE. Rest of the countries use IEC 60320 standard cords. It is an                           international standard for the certification of the power cord components.                     4​

5. So, the next time if you want to buy 5-15 to C13 power cords you will find                                   NEMA 5-15 to C13 power cords standardized. In the USA, the standard                         used to examine power cords is UL 817.  As this article has demonstrated, the power cords aren’t easy to                       understand. There are a number of components used, different regulations                     followed country wise. It is an essential conduit through which the                       electricity flows. Therefore, you need to take care while buying. They must                         meet the maze of international regulations and certifications for the power                       cords.  Source:  https://www.sfcable.com/blog/power-cords-connection-types-regulatory-is sues-explained/  5​