NEMA L12-20 — 3Ø 480 V, 20 A Twist-Lock Plug & Receptacle
NEMA L12-20 is a twist-locking configuration per NEMA WD-6: 3Ø 480 V, 20 A, 3-pole 3-wire non-grounding. Three-phase 480 V, no ground. The receptacle is L12-20R, the matching plug L12-20P.
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
- L12-20
- Series
- Locking (L / twist-lock)
- Voltage rating
- 3Ø 480 V
- Amp rating
- 20 A
- Poles / wires
- 3P–3W
- Neutral
- No
- Equipment ground
- No
- Max load (at rating)
- √3 × 480 V × 20 A = 16,628 VA
- Continuous (80%)
- 13,302 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
Three-phase 480 V, 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 L12-20R and L12-20P?
The letter is the device: L12-20R is the receptacle (outlet), L12-20P is the plug on the cord. Both share the same configuration — 3Ø 480 V, 20 A, 3-pole 3-wire non-grounding, twist-locking blades.
Does NEMA L12-20 have a neutral and a ground?
No neutral — the 3Ø 480 V rating means the circuit runs line-to-line with no neutral. It is a non-grounding configuration: no equipment ground, which is why new installations use its grounding successor.
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