Figure 7 – Delta connection – three phase, three wires. Amps per leg on three phase?? Three phase Amps = [HP * 746] / [E * %age Efficiency * PF * 1.73] Example: Determine the current flowing through a three-phase, 2 HP, 400-volt motor having an efficiency rating of 93% and a power … 230 volts motor - 3-phase : 2.5 amps/hp; 460 volts motor - 3-phase : 1.25 amps/hp; Always check nameplate information before designing protective devices, wiring and switch gear. 02-24-2017, 07:36 PM #2. As an example, consider a balanced three phase load consuming 36 kW at a power factor of 0.86 and line to line voltage of 400 V (V LL) : the line to neutral (phase) voltage V LN = 400/√3 = 230 V three phase power is 36 kW, single phase power = 36/3 = 12 kW now simply follow the above single phase method. I will do that tomorrow. Three phase kW to Amps calculations involve a ration of 1000 times kW to the power factor times voltage and an additional factor 1.73 that represents an equivalent of √3 and is added because the circuit is three phase in nature. A motor of a given rated horsepower is expected to deliver that quantity of mechanical power at the motor shaft. What is causing the .6 reading on one leg? The Wye configuration is used to distribute power to everyday single-phase appliances found in the home and office. Calculate three-phase motor power consumption by multiplying amps by volts by the square root of three (W = AV(sqrt 3). The power factor of resistive impedance load is equal to 1. Go back to Three phase power measurements ↑ Wye and Delta comparison. Three phase kW to Amps. Single-Phase Motors - HP and Full-Load Currents. The higher the voltage, the more efficient and powerfull the circuit will be. Depending on the primary and secondary voltage rating of the “3-phase transformer” and it’s winding configuration, (i.e. Convert watts to kilowatts by dividing the number of watts by 1,000. I should of checked the voltage. For example, if the motor is drawing 30 amps at 250 volts, you have 30 x 250 x sqrt 3 (about 1.73) = 12,975 watts). Single- phase loads are connected to one leg of the wye between line and neutral. Decided to check the amps on a three hp motor. Easy enough. AC three phase watts to amps calculation Calculation with line to line voltage. A 3 phase power outlet will have 3 wires for power, and if it is 220 volts you could measure 220 volts between any combination of the 3 wires. 3 Phase in N. America is normally available in 208, 220 or 240 or 480 or 600 volts (Canada). 3 PHASE AMPERES - 80% POWER FACTOR* (Extended Table) kW Times 1000 divided by (Volts*1.73) *.80 This chart approximates the amperage of a generator based on the size of the generator and the load on the generator at 100 percent of capacity. I got 9-.6-9 It sounds good. Jraef. FORMULAS USED IN CALCULATOR: 1-Phase KVA = Volts x Amps / 1000 1-Phase Amps = KVA / Volts x 1000 3-Phase KVA = Volts x Amps x 1.732 / 1000 3-Phase Amps = KVA / Volts / 1.732 x 1000