Normally tap selection range is ± 15 % in steps of 2.5 %. It is provided on HV side so that the voltage on LV side feeding to the load can be maintained. The taps of transformer can be changed by the tape changer manually. The tap changer is used to regulate the output voltage manually according to line voltage. These tubes provide better and effective cooling of transformer oil by increasing the surface area of tank to the atmosphere. It provides passage to drain the oil during overhauling or as and when required oil sample for testing.

It provides passage to pour the transformer oil in the tank during purification or in case of shortage found in the tank. Transformer consists of the following parts and components.įigure 1 – 3 Phase, 500 kVA, 11/0.433 kV Natural Air Oil Cooled Distribution Transformer It is basically a static electrical device which steps down the primary voltage of 33kV or 11 kV to secondary distribution voltage of 415-440 volts between phases and 215 volts between phase and neutral through delta-star windings by electromagnetic induction without change in frequency. The distribution transformer is a main and largest equipment of distribution substation. The following equipment are installed in distribution substations:

Lightening arresters, earthing of equipment and fencing is done for this purpose. Safety and protection of equipment as well as working personnel is also a considerable factor. 10 electrical equipment you can see in every distribution substation

Autocad electrical switch symbol