NEMA L18-30 — 3ØY 120/208 V, 30 A Twist-Lock Plug & Receptacle
NEMA L18-30 is a twist-locking configuration per NEMA WD-6: 3ØY 120/208 V, 30 A, 4-pole 4-wire non-grounding. Wye with neutral, no ground. The receptacle is L18-30R, the matching plug L18-30P.
No free-licensed face diagram exists for this configuration yet — locking faces are not on Wikimedia Commons. The specs below still identify it unambiguously.
Specifications
- Configuration
- L18-30
- Series
- Locking (L / twist-lock)
- Voltage rating
- 3ØY 120/208 V
- Amp rating
- 30 A
- Poles / wires
- 4P–4W
- Neutral
- Yes
- Equipment ground
- No
- Max load (at rating)
- √3 × 208 V × 30 A = 10,808 VA
- Continuous (80%)
- 8,646 VA
Load figures are the arithmetic of the device rating at unity power factor. Continuous loads (3 hours or more) are limited to 80% of the circuit rating per NEC 210.19/210.20 — and the branch circuit behind the receptacle comes from the load calculation and conductor sizing, not from the plug face.
Where you meet it
Wye with neutral, no ground. The locking blades twist in and cannot vibrate or pull loose — the reason generators, stage rigs, and equipment connections spec the L series over its straight-blade cousins.
RELATED CONFIGURATIONS
See every configuration on the full NEMA plug & receptacle chart →
Common questions
What is the difference between L18-30R and L18-30P?
The letter is the device: L18-30R is the receptacle (outlet), L18-30P is the plug on the cord. Both share the same configuration — 3ØY 120/208 V, 30 A, 4-pole 4-wire non-grounding, twist-locking blades.
Does NEMA L18-30 have a neutral and a ground?
Yes on the neutral — the 3ØY 120/208 V rating means the circuit includes a grounded (neutral) conductor. It is a non-grounding configuration: no equipment ground, which is why new installations use its grounding successor.
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