In the US, the most common type of power cables have an IEC connector that plugs into the server and a NEMA connector that plugs into the power source. IEC is an acronym for International Electrotechnical Commission.
IEC C13 & C14 Connectors
The IEC is an international standards organization that covers a huge range of technologies, however this discussion will be limited to common power cable connectors. There are 26 IEC connectors (13 plugs & 13 receptacles). The odd numbers are for the plugs, the even numbers are for the receptacles. So a C1 (plug) will plug into a C2 (receptacle). The most common type used for Dell, HP, & IBM servers is the the C13 & C14 connectors.
NEMA 5-15P and NEMA 5-15R
NEMA is an acronym for National Electrical Manufacturers Association. NEMA is a US based organization that establishes a wide range of standards for US electrical devices, however this discussion will be limited to common power cable connectors. The NEMA 5 connectors are the most common. These connectors are available in 15A, 20A, & 30A. The 5-15 is the most common connector used in the US. This connector is the typical type used for wall outlets and extension cords. Plugs and Receptacles are designated with P & R in the nomenclature. If there is an L in the nomenclature then the plugs and receptacles are twist locks. A NEMA L5-20P would designate a NEMA 5 20A plug that has a twist lock. The corresponding receptacle for this plug would be a NEMA L5-20R.
IEC C13 & NEMA 5-15P Connectors (PC and Server power cord)
Typically if you order a Dell, HP, or IBM server it will come with Power Cables that have an IEC C13 & NEMA 5-15P on the power cable. The important thing to check is where that power cable is plugging in. That receptacle will determine what type of connector you need when ordering power cables for your new hardware.
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