This is a single-phase choke coil loading inductor. This is required when experimenting to determine the output characteristics of devices like a transformer etc. For example, if you want to measure the effect of presence of an inductor, in a single-phase electrical circuit, then this loading inductor becomes a very useful accessory. Normally a loading rheostat (R), loading inductor (L) and loading capacitor (C) (popularly called as RLC loads) is associated in an electrical setup for the purpose of calculating efficiency of the circuit. This loading inductor is specially designed for experimenting in electrical laboratories.

This is arranged in a core type structure. The air gap in the coil is adjustable by a gradually moving, screw wheel mechanism. The air gap so adjusted is proportional to change in the magnetic reluctance. These changes make a variation in the current from 20% to the rated current. In general the coil voltage is 230V AC. The outputs are terminated on Banana terminals, for easy interconnections. The entire structure is made of heavy 1” angle iron pillars duly fastened to the wooden base. These are variable in 230V AC, at 1 to 10 Ampere capacity and continuously adjustable.