The wattage rating information for a particular device may be on a label or imprinted on the back somewhere. If no wattage rating is displayed, the load can be calculated by multiplying the amps drawn (appliance amps) by the voltage of the circuit. If neither the amps nor the wattage ratings for a device is known, the chart below lists common household appliances and the average watts drawn for each to aid in calculating the load of a circuit.
If the wiring is correct turn the power off and install the device in the outlet box. Carefully fold the wires to fit into the box and push the device with your palm until it sits flat and is aligned with the mounting holes. Drive the mounting strap screws and shift the replacement of the device left or right as necessary to square it in the box as you tighten them down. Install the cover plate, turn the circuit back on and test the device again.
Electric cable with spiral metal sheathing. Early armored cable, BX cable, carried two electric wires with no ground. The metal sheath served as the ground. Later versions carried an aluminum ground wire, wound in the spiral. Newer armored cable includes an insulated ground wire.
Try to remove the wallboard cleanly so it can be reattached when you’re done. The baseboard can be reinstalled without replacing the wallboard, but this will create easy access for pest such as rodents, as well as drafts from cold air during the winter.