PURPOSE: To control loads through controlling a primary current, by changing secondary currents through changing the value of the primary current, and by making switching circuits perform their outputting operations respectively according to the numbers of the turns of their associated secondary windings, and further, by feeding respectively the secondary currents only to the loads whereto their associated switching circuits are switched on respectively.

CONSTITUTION: In a load controlling apparatus, a primary winding 1, a plurality of secondary windings 2-4, sensing circuits 5, switching circuits 7, and loads 8 are provided respectively, and a plurality of secondary windings 2-4 are coupled electromagnetically to the primary winding 1 and each of them has a different number of turns from others. Hereupon, when a power is fed to the primary winding 1 and the value of a primary current is changed, the values of secondary currents are changed. Since the numbers of the turns of the secondary windings 2-4 are different from each other, the sensing circuits 5 performing their outputting operations respectively and the ones performing no outputting operation are made present. Thereby, only to the loads 8 whereto their associated switching circuits 7 are switched on respectively, the secondary currents are fed. Therefore, by the control of the primary current, the loads 8 can be controlled.