NEMA Plug & Receptacle Identifier

Each of the charts behind this tool prints a handful of configurations the others leave out, in both directions. When only one of them shows a configuration, this tool names it and tells you which chart it came from rather than publishing a spec it cannot double-check. So a device missing from the tables below is usually one we have seen once, not one that does not exist.

On a few twist-lock rows one chart abbreviates its heading and leaves the word grounding off. Those configurations publish only when the second manufacturer states the ground in words. Grounding is the one field worth being slow about, because 10-30 and 14-30 are both 30A at 125/250V and only one of them has an equipment ground.

Those ratings are read from manufacturer product listings rather than a dated catalog, so they can be updated without a new edition being published. The values here were read on 2026-07-25 and the exact pages are listed in the record below.

• Hubbell Configuration Chart (Wiring Device-Kellems) (hubbellcdn.com/ohwassets/HCI/WiringDevice/media/NEMA_Chart.pdf), Footer document code WLCMNEMA17. Published on hubbell.com, bytes served by hubbellcdn.com, read 2026-07-25, md5 e450b7033f806d07d9503d5ca2e20236, 3,191,369 bytes.
• Leviton Industrial Wiring Devices Catalog (leviton.com/content/dam/leviton/commercial-industrial/product_documents/brochure/Industrial Wiring Devices Catalog.pdf), 142-page industrial catalog, retrieved 2026-07-25. Published on leviton.com, read 2026-07-25, md5 d685d8eb9681f83d9f843fcb804bc064, 9,556,937 bytes.
• Leviton product pages (straight blade 30A, 50A and 60A) (leviton.com/products/{5372, 5378, 5054, 5050, 278, 279, 9460, 55050}), Live product pages, retrieved 2026-07-25. Published on leviton.com, read 2026-07-25.
• Eaton Arrow Hart Color-Coded Locking Devices NEMA Selector Guide (eaton.com/content/dam/eaton/products/wiring-devices-and-connectivity/wiring-devices/locking-devices/color-coded-locking-devices/color-coded-printed-book.pdf), Colour-coded locking selector guide, 20 pages. Published on eaton.com, read 2026-07-25, md5 0ad45c48cc7b6482667593c18f506bc4, 974,808 bytes.

Hubbell's chart prints the pole/wire class as a row header ("2 Pole / 3 Wire Grounding", "3 Pole / 3 Wire") and the amperage as a column header, with the designation printed under each device symbol. Leviton's catalog states the same classes in words per block ("3-Pole, 4-Wire Grounding"). For straight blade above 20A, Leviton's product pages state it inline, quoted verbatim: "50 Amp, 125/250 Volt, NEMA 14-50R, 3P, 4W, Flush Mtg Receptacle, Straight Blade, Grounding, Side Wired, Steel Strap" (cat. 279) and "50 Amp, 125/250 Volt, NEMA 10-50R, 3P, 3W, Surface Mtg Receptacle, Straight Blade, Industrial Grade, Non-Grounding, AL-CU, Side Wired, Steel Strap" (cat. 5050).

Answer three things you can see without any measurement: whether the blades are straight (it pushes in) or curved (it twists to lock), how many slots or blades there are in total, and whether one of them is a round or D-shaped ground pin. Those three narrow the published set a long way. If the amperage is legible on the device face, that usually finishes the job. Where the visible evidence genuinely fits more than one configuration, this tool shows all of them rather than picking, and it names what still separates them. Usually that is the stamped voltage or amperage, both of which the tool will take as a further answer. Only when the candidates match on everything else and differ purely by amperage is what remains blade geometry, which lives in NEMA WD 6 and is a layer we have not added yet; in that case the tool shows every match rather than guessing.

A designation like 14-50R splits into three parts. The 14 is a line number that fixes the pole count, wire count and voltage class. The 50 is the amperage. The trailing R means receptacle and P means plug. An L in front, as in L6-30P, means twist-lock. The important catch is that the line number and the amperage are independent, so a designation can be perfectly well formed and still not name a real device: nobody manufactures an L7-60 even though the string parses cleanly. This tool decomposes any well-formed designation and then tells you separately whether it is one that manufacturers actually print.

14-50R is one configuration: 50A at 125/250V AC, 3 pole, 4 wire, with an equipment ground. The blade pattern is fixed, so any 14-50 plug mates with any 14-50 receptacle. What differs between products is build quality, mounting style and terminal type, not the configuration. Do not confuse it with 10-50R, which is the older three-wire version at the same amperage and voltage and has NO equipment ground.

Grounding, and it is the difference that matters. Both are 30A at 125/250V AC. The 10-30 is 3 pole, 3 wire, with no equipment ground: the neutral and the ground were bonded at the appliance. The 14-30 is 3 pole, 4 wire, with a separate equipment ground. That is why a dryer outlet swap is not just a plug change, and why this tool prints the grounding answer as its own line rather than leaving you to infer it from the slot count.

Because a cell publishes here only when two independent manufacturers print it and agree on every field. One manufacturer restating itself on a second page is not a second source. That rule leaves 35 designations we name and refuse: 33 that exactly one of our documents prints, 1 that both print without both stating every field, and 1 that neither prints at all. The tool names each one and says which direction the gap runs. Our sources genuinely disagree about which lines exist: Leviton prints L12 and L13, and the Hubbell chart has no row for either. A tool built on one chart would have told you those are not NEMA configurations, which is false. Line 11 was in that same position until a third manufacturer, Eaton, was read and confirmed it, which is exactly what moves a configuration from held back to published here.

This tool gives you amperage, voltage, poles, wires and grounding, corroborated across two independent manufacturers. Blade and slot dimensions live in NEMA WD 6 and are a separate layer we have not added yet.

No, and the reason is worth stating. TT-30 is the RV travel-trailer configuration and it appears on neither chart we fetched: both are general wiring-device references and RV and marine configurations sit outside them. We hold no source for it, so we publish nothing about it rather than filling the gap from memory.