How to Wire a 15A – 250V Outlet (NEMA 6-15): The Complete NEC Guide
How to wire a NEMA 6-15 Receptacle?
To wire a NEMA 6-15R (15A, 250V), you need a Double-Pole 15A Circuit Breaker and #14 AWG Copper Wire. This is a 240V circuit with NO neutral. Connect Hot 1 (Black) to the left brass screw, Hot 2 (Red or Taped-White) to the right brass screw, and Ground to the green screw.
NEMA 6-15 (240V): Two horizontal blades (— —) and a ground pin.
NEMA 5-15 (120V): Two vertical blades ( | | ) and a ground pin.
They look similar in size but carry double the voltage. Always verify the receptacle face before installation. Understanding the difference between socket vs outlet vs receptacle terminology can also help avoid confusion.
1. What is a NEMA 6-15 Receptacle?
The NEMA 6-15R is a grounded receptacle designed for 250V single-phase equipment drawing up to 15 Amps. It is commonly found in workshops for tools like table saws, large window AC units, or commercial lighting ballasts.
2. Electrical Ratings & Required Materials
| Specification | Requirement | Notes |
|---|---|---|
| Wire Size | #14 AWG Copper | Minimum size. #12 AWG is also acceptable. |
| Voltage | 250V (240V Nominal) | Single Phase, 60Hz. |
| Breaker | 15A Double-Pole | Do not use single-pole breakers. For panel work, see our low voltage electrical cabinet maintenance guide. |
| Torque | 14-18 lb-in | Tighten securely to prevent arcing. |
| Max Wattage | 3,600 Watts | Continuous load limit: 2,880W (80%). |
3. Step-by-Step Wiring Installation
Shut Off Power & Test
Turn off the Double-Pole 15A Breaker. Use a voltage tester to verify the box is dead. Safety first! If you are unfamiliar with using testing equipment like multimeters (often used to test a capacitor or check voltage), please consult a professional.
Prepare Wires (Re-identification)
If you are using standard 14/2 or 12/2 cable (Black, White, Bare):
- Black Wire: Hot 1
- White Wire: MUST be wrapped with Red or Black Electrical Tape. This signifies it is now a HOT wire, not a neutral (NEC 200.7).
- Bare Wire: Ground
Make Connections
Connect Ground First: Attach the Bare/Green wire to the Green Hex Screw.
Connect Hot Wires:
- Connect the Black wire to one Brass Screw.
- Connect the Taped-White wire to the OTHER Brass Screw.
(Order of hot wires doesn’t matter, as long as they are on the brass screws).
Panel Connection
At the panel: Ground to Ground Bar. Connect the Black and Taped-White wires to the two terminals of the Double-Pole 15A Breaker. If you notice any issues with your panel during this step, such as overheating or buzzing, you may need a professional electrical system maintenance service.
4. NEC Codes & GFCI Rules
NEC 210.8 (GFCI Requirement)
For 240V outlets in garages, basements, outdoors, or near sinks, GFCI protection is MANDATORY. You must use a 2-Pole GFCI Breaker since the receptacle itself does not have GFCI buttons.
NEC 210.21(B)(3) (Multiple Receptacles)
You can install multiple 15A (6-15R) outlets on a single 15A or 20A circuit. However, you cannot put a single 15A outlet on a 20A dedicated circuit unless it’s a duplex receptacle (which counts as two).
5. Frequently Asked Questions
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