Too many items plugged into a circuit can cause an overload. Exceeding the limit should automatically shut off the circuit at the main panel. Power strips don’t always protect you.
A dedicated circuit serves a single large-draw appliance like the stove or furnace.
The general-purpose circuits serve multiple sources as lights and plugs.
But, if you connect a high-power use appliance like heaters or an air conditioner, you may need it on only a dedicated circuit.
Maximum load: For 15 amp circuit – 120 volts x 15 amps = 1800 watts. For 20 amp circuit – 120 volts x 20 amps = 2400 watts.
Maximum load on each circuit isn’t the goal because a margin of safety of 80% is best. For a 15-amp circuit, the safe load is 1,440 watts; for a 20-amp circuit, it’s 1,920 watts. On a multiple-outlet circuit, limit any individual appliance to half the circuit rating – 900 watts for a 15-amp circuit.
If all the connections add up to more than the limit allowed by the National Electrical Code, you need to remove some load to other circuits or run a new circuit for the largest appliances to avoid overloads.
Signs of an electrical circuit overload or short circuits:
- Tripping a breaker.
- Burning smell.
- Lights dimming when you turn on appliances or more lights.
- Burnt or discolored outlets.
- Buzzing outlets or switches.
- Warm light switch covers.
- Appliances, tools or electronics lack power.