240 V receptacle wiring diagram
Light: on
Both legs are live — the load sees the voltage between them, and the breaker opens both at once. There is no neutral in this three-wire load. The copper highlight is the live loop, not a wire colour.
A 240 V load sits across two live legs, not between a hot and a neutral. Each leg is an ungrounded conductor; the load sees the voltage between them. A bonding conductor is there for safety, and a two-pole breaker opens both legs at once. In this three-wire arrangement there is no neutral at all.
How this circuit works
Current leaves on one leg, passes through the load, and returns on the other leg. There is no third current-carrying wire to make it work — the two legs are the whole circuit. Because both are live, both have to be switched, which is what the ganged two-pole breaker is for. Open it and watch the entire loop go cold in the diagram.
Where a neutral does appear on a 240 V circuit, it is because the appliance has 120 V controls or accessories inside it, and that is the four-wire case. The pure heating or motor load shown here needs only the two legs and the bond.
Questions people ask
Where is the neutral on a 240 V receptacle?
In a straight three-wire 240 V load there is no neutral — the load sits across two live legs, with a bonding conductor for safety. Some appliances also want a neutral for their 120 V controls, and those use a four-wire arrangement. The diagram shows the three-wire case: two legs and a bond.
Are both legs really hot?
Yes. Both legs are ungrounded conductors, each live with respect to ground. The load sees the voltage between them. That is why the diagram lights the whole loop in copper and why a two-pole breaker is used — you have to open both legs to make the load safe.
Why a two-pole breaker?
Because there are two hot legs feeding the load, and both must be disconnected together. A two-pole breaker ties its handles so throwing one throws both. Open it in the diagram and both legs go dead at once.
Related
- Glossary: bonding vs grounding — what that third conductor does.
- Contactor wiring diagram — switching larger loads with a coil.
- All wiring diagrams
Learn one thing a week
Now and then a new diagram, drill, or reference sheet goes up. Leave your email for a short heads-up when it does — no spam, no selling it on, one click to leave.