# NEMA locking (twist-lock) plugs L5-15 to L23-30: voltage, poles, wires and amp rating by family (L5-20, L6-20, L6-30, L14-30, L21-30)

> What is the difference between NEMA L5-20, L6-20, L6-30, L14-30 and L21-30 locking plugs?

- Category: Electronic components › Connectors
- Kind: Standard part
- Basis: Elliott Electric's NEMA twist-lock chart, AutomationDirect's wiring-devices catalog and Wikipedia's NEMA connector article; configuration table only, no blade dimensions and no files
- Page: https://xemstudio.com/objects/nema-locking-plugs-l5-l6-l14-l21/ · JSON: https://xemstudio.com/api/geometry?object=nema-locking-plugs-l5-l6-l14-l21 · Plain text: https://xemstudio.com/objects/nema-locking-plugs-l5-l6-l14-l21/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no tolerance added.

## Notes

- Reading a name: L = locking (twist-lock, curved blades), the number after it is the family (voltage, poles and wires), the number after the hyphen is the amp rating, and a trailing P / R / C is plug, receptacle or corded connector (flanged inlet FI and outlet FO also exist). So L5-20P is a 20 A, 125 V, 2-pole 3-wire grounded locking plug; L6-30R is a 30 A, 250 V receptacle; L14-30P is 30 A, 125/250 V, 3-pole 4-wire grounded; L21-30P is 30 A, three-phase wye 120/208 V, 4-pole 5-wire grounded.
- Sources: Elliott's chart gives voltage, poles / wires and the amp ratings for each family; AutomationDirect's catalog tables list the individual configurations with amps, volts, poles and wires for L5 to L9, L14 to L17, L21 and L22; Wikipedia adds L10 to L13 and L19 to L21 wording. Where they differ both are shown: Elliott calls L10 '3-pole, 3-wire ungrounded' and Wikipedia '2-pole + neutral, non-grounding'; Elliott calls L19 and L20 '4-pole, 4-wire' and Wikipedia '3-pole, four-wire'. L17 appears only in AutomationDirect's tables.
- Not given: blade and pin dimensions of the locking configurations. They are in ANSI/NEMA WD 6, which is sold, and Wikipedia states no locking dimensions. The blade numbers for L5-30 and L14-30 that public summaries print are on nema-plug-receptacle-configurations; this page adds the other families.
- Elliott's page has visible linking slips (for example the L11 plug row links to an L10-20P page and L23 receptacles link to L22 pages); only the printed chart text is used. A 15 A rating is shown only where the chart lists it (L5, L6, L7; Wikipedia also names L11-15).
- No file: a plug drawn from the voltage and amp rating would not be the part you can buy. Maker CAD: McMaster-Carr lists twist-lock devices with per-part STEP; not linked here.

## Sizes

| family | voltage as published | poles / wires | amp ratings (A) | notes |
|---|---|---|---|---|
| L5 | 125 V | 2-pole, 3-wire, grounded | 15, 20, 30 | AD lists L5-15, L5-20, L5-30 |
| L6 | 250 V | 2-pole, 3-wire, grounded | 15, 20, 30 | AD lists L6-15, L6-20, L6-30 |
| L7 | 277 V AC | 2-pole, 3-wire, grounded | 15, 20, 30 | AD lists L7-15, L7-20, L7-30 |
| L8 | 480 V AC | 2-pole, 3-wire, grounded | 20, 30 | AD lists L8-20, L8-30 |
| L9 | 600 V AC | 2-pole, 3-wire, grounded | 20, 30 | AD lists L9-20, L9-30 |
| L10 | 125/250 V | 3-pole, 3-wire, ungrounded | 20, 30 | Wikipedia words it '2-pole + neutral, non-grounding' |
| L11 | 3-phase 250 V | 3-pole, 3-wire, ungrounded | 20, 30 | Wikipedia also names L11-15 |
| L12 | 3-phase 480 V | 3-pole, 3-wire, ungrounded | 20, 30 |  |
| L13 | 3-phase 600 V | 3-pole, 3-wire, ungrounded | 30 |  |
| L14 | 125/250 V | 3-pole, 4-wire, grounded | 20, 30 | AD lists L14-20, L14-30 |
| L15 | 3-phase 250 V | 3-pole, 4-wire, grounded | 20, 30 | AD lists L15-20, L15-30 |
| L16 | 3-phase 480 V | 3-pole, 4-wire, grounded | 20, 30 | AD lists L16-20, L16-30 |
| L17 | 3-phase 600 V | 3-pole, 4-wire, grounded (AD) | 30 | AD lists L17-30; not on Elliott's chart |
| L18 | 3-phase wye 120/208 V | 4-pole, 4-wire, ungrounded | 20, 30 | Wikipedia: '4-pole, no ground' |
| L19 | 3-phase wye 277/480 V | 4-pole, 4-wire, ungrounded (Elliott) | 20, 30 | Wikipedia words it '3-pole, four-wire, non-grounding': poles disagree |
| L20 | 3-phase wye 347/600 V | 4-pole, 4-wire, ungrounded (Elliott) | 20, 30 | Wikipedia words it '3-pole, four-wire, non-grounding': poles disagree |
| L21 | 3-phase wye 120/208 V | 4-pole, 5-wire, grounded | 20, 30 | AD lists L21-20, L21-30 |
| L22 | 3-phase wye 277/480 V | 4-pole, 5-wire, grounded | 20, 30 | AD lists L22-20, L22-30 |
| L23 | 3-phase wye 347/600 V | 4-pole, 5-wire, grounded | 20, 30 | AD shows L23-20R and L23-30R in its wiring diagrams only |

## Where the files are

- Elliott Electric: [NEMA twist lock plug, receptacle and connector configuration chart (L5 to L23; voltage, poles, wires, 15 / 20 / 30 A)](https://elliottelectric.com/nema-twist-lock-plug-receptacle-connector-chart.aspx) — web — Publisher's page; dimensions are facts
- AutomationDirect: [Wiring devices: plugs, connectors and receptacles catalog (locking L5 to L22: amps, volts, poles, wires)](https://cdn.automationdirect.com/static/specs/wiringdevicesplugsconnsreceps.pdf) — web — Publisher's page; dimensions are facts
- Wikipedia: [NEMA connector (locking L-series: voltage, poles, wiring; curved-blade twist-locking)](https://en.wikipedia.org/wiki/NEMA_connector) — web — CC BY-SA 4.0 (text); ratings are facts

## Questions

**What is a NEMA L5-20 plug?**

A 20 A, 125 V, 2-pole 3-wire grounded locking (twist-lock) plug (Elliott chart, AutomationDirect).

**What is the difference between L6-30 and L14-30?**

L6-30 is 30 A, 250 V, 2-pole 3-wire grounded; L14-30 is 30 A, 125/250 V, 3-pole 4-wire grounded (two hots, neutral, ground).

**What voltage is a NEMA L21-30?**

Three-phase wye 120/208 V, 30 A, 4-pole 5-wire grounded (Elliott chart and AutomationDirect).

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