FIELD GUIDESource-led reference

Side by side

NEMA 10-50R versus 14-50R receptacles

Is the documented 50 A-class receptacle the legacy non-grounding 10-50R form or grounding four-wire 14-50R form?

Computer-generated illustration, not a photograph.
P290 · ConnectorNEMA 10-50R receptacle
Computer-generated illustration, not a photograph.
P280 · ConnectorNEMA 14-50R receptacle

How they differ

  • NEMA 10-50R receptacle Read the NEMA identifier and qualified electrical documentation; this record is identification-only and does not approve a legacy-circuit modification.
  • NEMA 14-50R receptacle Read the NEMA identifier and exact circuit/device documentation before treating a receptacle as a candidate.

Then askIs the documented 50 A-class receptacle the legacy non-grounding 10-50R form or grounding four-wire 14-50R form?

At a glance

Source-scoped form facts; counts, variants and unknowns are distinct
FieldNEMA 10-50R receptacleNEMA 14-50R receptacle
TypeConnectorConnector
FamilyPowerPower
Shapeslotslot
Nominal contacts3S319Source-backed nominal position/contact/conductor count for identification: 3. Not a wiring diagram or installation instruction.4S309Source-backed nominal position/contact/conductor count for identification: 4. Not a wiring diagram or installation instruction.
Positions / cavity spanNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Contact rowsNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Connector rolesocket (5050-P00)S319Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. 5050-P00. Documented role: socket. Manufacturer specification for named part only. No mating-face pin numbering, connector dimension or contact pitch inferred from wire acceptance ranges.; SEO heading says Grounding; detailed product description and Electrical Specifications say Non-Grounding. Retain conflict in source qualification; no universal wiring claim.socket (55050-P00)S309Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. 55050-P00. Documented role: socket. Manufacturer specification for named part only. No mating-face pin numbering, connector dimension or contact pitch inferred from wire acceptance ranges.
Key distinctionA familiar shell, blade or coding family does not establish voltage, current, wiring, grounding, mating or safe operation.A familiar shell, blade or coding family does not establish voltage, current, wiring, grounding, mating or safe operation.

Full evidence ledger and sources ↓

Illustrations are computer-generated with prior AI visual review; independent technical and rights review pending. A comparison is not a compatibility verdict.

This comparison stays within one evidence layer.

All selected records are Connector records. Similar layer does not mean compatible, interchangeable or safe to mate.

Families represented: Power

The reference ledger

Read the same question across.

2 selected records · 13 fields
No score. No compatibility verdict.

On a narrow screen, scroll the table sideways or open the field-by-field reading view below. Illustrations are not a size comparison.

Comparison of selected field notes; source links accompany each documented specification
What you are comparing
NEMA 10-50R receptacle — original, not-to-scale identification schematic; drawing review pending
P290 / ConnectorNEMA 10-50R receptacle

Identification schematic · not to scale · drawing review pending

NEMA 14-50R receptacle — original, not-to-scale identification schematic; drawing review pending
P280 / ConnectorNEMA 14-50R receptacle

Identification schematic · not to scale · drawing review pending

LayerConnectorConnector
Key distinctionA familiar shell, blade or coding family does not establish voltage, current, wiring, grounding, mating or safe operation.A familiar shell, blade or coding family does not establish voltage, current, wiring, grounding, mating or safe operation.
Nominal contacts3S319Source-backed nominal position/contact/conductor count for identification: 3. Not a wiring diagram or installation instruction.4S309Source-backed nominal position/contact/conductor count for identification: 4. Not a wiring diagram or installation instruction.
Positions / cavity spanNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Populated contactsNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Contact rowsNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Contact pitchNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Dimensions / axisNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Connector rolesocket (5050-P00)S319Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. 5050-P00. Documented role: socket. Manufacturer specification for named part only. No mating-face pin numbering, connector dimension or contact pitch inferred from wire acceptance ranges.; SEO heading says Grounding; detailed product description and Electrical Specifications say Non-Grounding. Retain conflict in source qualification; no universal wiring claim.socket (55050-P00)S309Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. 55050-P00. Documented role: socket. Manufacturer specification for named part only. No mating-face pin numbering, connector dimension or contact pitch inferred from wire acceptance ranges.
Coupling / latchNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Keying / polarizationNot recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Documented identification3-position/contact/conductor recognition fact in the cited implementation.C290A4-position/contact/conductor recognition fact in the cited implementation.C280A
EvidenceC290A,C290B →
Independent review pending
C280A,C280B →
Independent review pending
Read field by field — no sideways scrolling

The same selected records, fields, values and source links as the table. Missing fields remain non-equivalent; no values are merged.

Layer

NEMA 10-50R receptacleP290 / Connector
Connector
NEMA 14-50R receptacleP280 / Connector
Connector

Key distinction

NEMA 10-50R receptacleP290 / Connector
A familiar shell, blade or coding family does not establish voltage, current, wiring, grounding, mating or safe operation.
NEMA 14-50R receptacleP280 / Connector
A familiar shell, blade or coding family does not establish voltage, current, wiring, grounding, mating or safe operation.

Nominal contacts

NEMA 10-50R receptacleP290 / Connector
3S319Source-backed nominal position/contact/conductor count for identification: 3. Not a wiring diagram or installation instruction.
NEMA 14-50R receptacleP280 / Connector
4S309Source-backed nominal position/contact/conductor count for identification: 4. Not a wiring diagram or installation instruction.

Positions / cavity span

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Populated contacts

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Contact rows

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Contact pitch

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Dimensions / axis

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Connector role

NEMA 10-50R receptacleP290 / Connector
socket (5050-P00)S319Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. 5050-P00. Documented role: socket. Manufacturer specification for named part only. No mating-face pin numbering, connector dimension or contact pitch inferred from wire acceptance ranges.; SEO heading says Grounding; detailed product description and Electrical Specifications say Non-Grounding. Retain conflict in source qualification; no universal wiring claim.
NEMA 14-50R receptacleP280 / Connector
socket (55050-P00)S309Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. 55050-P00. Documented role: socket. Manufacturer specification for named part only. No mating-face pin numbering, connector dimension or contact pitch inferred from wire acceptance ranges.

Coupling / latch

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Keying / polarization

NEMA 10-50R receptacleP290 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
NEMA 14-50R receptacleP280 / Connector
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.

Documented identification

NEMA 10-50R receptacleP290 / Connector
3-position/contact/conductor recognition fact in the cited implementation.C290A
NEMA 14-50R receptacleP280 / Connector
4-position/contact/conductor recognition fact in the cited implementation.C280A

Evidence

NEMA 10-50R receptacleP290 / Connector
C290A,C290B →
Independent review pending
NEMA 14-50R receptacleP280 / Connector
C280A,C280B →
Independent review pending

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Evidence behind this page

Scope first. Source second. Approval separate.

2 linked sources · 4 scoped claims · 0 sources with inspection/access flags.

Page scope: Evidence behind the compared records; the editorial comparison still needs separate review.

Assessment 2026-10-22 · earliest scheduled source review 2027-01-04. This is a recorded-date assessment, not a live source check. Page-level independent review is not established by this panel.

Inspect 2 source scopes, access limits and dates

S309 · 55050-P00 NEMA 14-50R receptacle

Leviton · Manufacturer / product-owner domain · inspected 2026-10-06 · due 2027-01-04

Within inspection window

Scoped support: Primary manufacturer identification reference for NEMA 14-50R receptacle: V47 normalizes the named connector designation and 4-position/contact/conductor context only.

Not established / limitations: Identification/reference scope only. V47 does not turn this source into a universal wiring map, installation approval, safe-use recommendation, fabrication drawing or end-to-end compatibility verdict.

Locator: Product description and Technical Information

S319 · 5050-P00 NEMA 10-50R receptacle

Leviton · Manufacturer / product-owner domain · inspected 2026-10-06 · due 2027-01-04

Within inspection window

Scoped support: Primary manufacturer identification reference for NEMA 10-50R receptacle: V47 normalizes the named connector designation and 3-position/contact/conductor context only.

Not established / limitations: Identification/reference scope only. V47 does not turn this source into a universal wiring map, installation approval, safe-use recommendation, fabrication drawing or end-to-end compatibility verdict.

Locator: Product description and Technical Information

Trace 4 claims to their source records

C280A · P280

Leviton identifies 55050-P00 as a NEMA 14-50R, 50 A, 125/250 V, 3-pole 4-wire grounding receptacle.

Claim scope: V47 identification fact only; the cited product establishes the named connector/configuration and narrow position/conductor context, not universal wiring, mating, installation safety or interchangeability.

Source links: S309 · Evidence trail → (private workspace)

C280B · P280

Exact source example 55050-P00: construction: Surface-mount3pole4wire grounding receptacle; side-wired; thermoplastic body and galvanized-steel strap. rating: 50 A125/250 V. Exact manufacturer part; construction, role and regional rating remain scoped. No physical compatibility, pin map or hardware validation is established.

Claim scope: Exact named component/family technical construction reference from the full current primary document; geometry, ratings and implementation limits do not transfer to other variants.

Source links: S309 · Evidence trail → (private workspace)

C290A · P290

Leviton identifies 5050-P00 as a NEMA 10-50R, 50 A, 3-pole 3-wire non-grounding receptacle.

Claim scope: V47 identification fact only; the cited product establishes the named connector/configuration and narrow position/conductor context, not universal wiring, mating, installation safety or interchangeability.

Source links: S319 · Evidence trail → (private workspace)

C290B · P290

Exact source example 5050-P00: construction: Surface-mount3pole3wire non-grounding receptacle per detailed description; thermoplastic body; side-wired galvanized-steel strap. rating: 50 A125/250 V. Exact manufacturer part; construction, role and regional rating remain scoped. No physical compatibility, pin map or hardware validation is established.

Claim scope: Exact named component/family technical construction reference from the full current primary document; geometry, ratings and implementation limits do not transfer to other variants.

Source links: S319 · Evidence trail → (private workspace)

Prepare this page for review → (private workspace)Read the evidence method →

Recorded evidence only. An inspection date, publisher label, source link or generated packet is not independent technical review, hardware testing, fabrication approval or a compatibility verdict.