An electric stove, like an electric water heater or dryer, is an energy-intensive appliance. The electric code requires a stove to be connected to the main electrical panel by a dedicated circuit, and it stipulates the gauge of the wire you use to connect it, depending on the amount of power it draws. A double-pole breaker must control the circuit, and its rating, in amperes, must match that of the stove.
240-Volt Wiring Basics
An electric stove is a 240-volt appliance, and the circuit that powers it must be wired differently than light circuits or those powering smaller appliances. A 240-volt circuit draws power from both hot bus bars in the main electrical panel, instead of just one, which means that the cable has two hot wires, as well as a return wire and a ground. Each hot wire must connect to a separate circuit breaker, but the breakers must be coupled so that if one trips, the other will also trip, thereby completely de-energizing the circuit.
Stove Circuit Breakers
The rating of the circuit breakers you use for a stove circuit must match the maximum amperage rating of the stove. You can find this rating imprinted on a metal tag affixed to the appliance, usually near the point where the plug attaches. Most stoves are rated for 50 amps, but some smaller ones may only be rated for 40, while larger ones can be as high as 60 or more. Because 240-volt breakers are coupled, you need two adjacent slots on the panel in which to install them. Each automatically contacts a different bus bar so that the voltage between the wires attached to them is 240 volts.
The size of electrical wire is denoted by its wire gauge or AWG (American Wire Gauge) number. Gauge varies inversely with wire diameter, so the lower the gauge, the thicker the wire. Thicker wires transmit electricity more efficiently than thinner ones with less resistive heating, but since they are more expensive and difficult to install, electricians tend to use the highest gauge wire permissible. 14- and 12-gauge wires are suitable for most 120-volt applications, but 10-gauge is the minimum size allowed for 240-volt wiring. The breaker controlling the circuit determines the exact size of wire that you should use.
Stove Wire Requirements
Since stoves generally draw from 40 to 50 amps, it is permissible to wire them with 8-gauge wire. If your stove draws 50 amps, however, you will ensure adequate power to the stove and avoid the danger of overheated wires by using 6-gauge wire. You must use 6-gauge wire if your stove is rated for more than 50 amps. Wire gauge is imprinted on electrical cable sheathing together with another number that denotes the number of conductors, not including ground. A 240-volt circuit uses 3-conductor wire, so your stove circuit requires either 8/3 or 6/3 cable, depending on the stove and breaker ratings.