- With the lowest amperage available, white Romex has a load capacity of 15 amps. It is commonly used for outlets, lights and smoke detectors in the home. This 14-gauge wire is called 14-2 when two insulated wire conductors are included and 14-3 with three wires.
- The heavier, yellow Romex is rated at 20 amps. Common applications for this 12-gauge wire are receptacles and three-way circuits. Larger appliances, such as a microwave or welder, require the additional power this wire delivers.
- There is a significant weight difference between the 14- and 12-gauge Romex. White Romex with two wires, 14-2, weighs 57 pounds for every 1,000 feet of wire. With three wires, 14-3, the weight increases to 74 pounds. Compare this to the weight of yellow Romex at 82 pounds. for 12-2 and 107 pounds for 12-3 wire.