What minimum size THW branch circuit conductors are required for a 240-volt, 4-kilowatt electric baseboard heater?

To determine the minimum size for THW branch circuit conductors used for a 240-volt, 4-kilowatt electric baseboard heater, it's essential to calculate the required current. Using the formula for power (P), which is expressed as P = V x I, we first solve for the current (I).

Given a power rating of 4,000 watts (4 kilowatts) and a voltage of 240 volts, we can rearrange the formula to find the current:

I = P / V = 4000 watts / 240 volts = approximately 16.67 amperes.

Now, according to the National Electrical Code (NEC), for continuous loads, conductors must be sized to handle 125% of the load. Hence, we calculate 125% of our current:

16.67 amperes x 1.25 = 20.84 amperes.

In terms of wire gauge sizing, a 10 AWG copper wire is typically rated for 30 amperes, making it suitable for this application as it exceeds the required current carrying capacity. This ensures that the conductors can safely handle the load without overheating, maintaining compliance with the NEC for safe electrical installations.

Therefore, the selection of