Exchange regulator is apparent nominal power output rated capacity, due to the power factor COSφ ≠ 1, so that the regulator can actually output active power: kW = Capacity (kVA) × COSφ. Therefore, when the actual selection should be a reasonable choice of power supply according to the electrical equipment of rated power, power factor and load type and other specific conditions, the output power should leave appropriate margin, specific selection safety factor as follows:
Purely resistive loads such as: Incandescent, resistance wire, electric furnace and other equipment, the capacity of the regulator selection 1.25-1.5 times the actual electricity load power sum on it.
Inductive loads, such as: fluorescent lamps, air conditioners, washing machines, refrigerators, fans, motors, CNC machine tools and other equipment, the selection should take into account the starting current load is particularly large, the capacity of the regulator should be used in actual electricity load power sum 2.5-3 times on it. If the input voltage is relatively low, considering the output capacity graph, and then adjust capacity. For example the user has the following inductive load: three-phase motor 2.2kW 1 Taiwan, 5.5 kW 1 station, the choice of the regulator is calculated as follows: the regulator capacity ≥ (2.2kW + 5.5 kW) × 2.5 = 19.25 kVA, that is, at least to choose three phase TNS-20 kVA or more specifications of the regulator is appropriate, above the rated input voltage input voltage ± 10% calculation, if the input voltage is below the rated input voltage of ± 10%, taking into account the capacity curve.
Capacitive load, the load is less, the regulator specifications should be 2 times more than the choice of load power.