Voltage Drop Formula

Voltage Drop =    Watts x Cable Length x 2  Wire Constant

Variables

Watts (W) = measures the electrical power or the rate of energy transfer being drawn by all the fixtures on the cable run

Cable Length [in feet] = the one-way distance of the cable

Constants

2 = accounts for the round-trip the current path takes back to the transformer

Wire Constant = pre-calculated value based on common wire gauges installed in low-voltage systems