Electricity can then be more easily transported. They are of different size: huge (Multi – ton units) which are used in power plants; intermediate – which are used in electric poles; and smaller transformers which are used in electronic equipments or appliances at homes or offices.
Two types of transformers: Core form transformers, shell form transformers. This distinction is based on construction of the core of a transformer. In the core form, windings surround the iron core whereas in the shell form there is a shell or a frame which surrounds the windings. Despite of the design every transformer has an iron core, primary and secondary windings, and insulation also transformer accessories such as wire harness, mechanical casing and bushing.
Electricity has to travel a long way from power plants to homes and offices. This is a very long destination travel and needs 'stepping down' of voltage along the way. The power first leaves from a power plant where the voltage is very high; it reaches electric poles where it gets stepped down to lesser voltage (which is less dangerous) then it is transported to final destination (equipments, appliances) where again power transformers 'step down' the voltage for more manageable state.
The main functionality of power transformers is to make use of electricity without the risk of destroying the internal circuitry of any equipment because of the flow of high voltage.
Did you know voltage in different parts of the world differ? Different countries follow different standards of power and it would prove to be very expensive to change back to a single universal system. United States and Canada run on 110/120 volts and all other parts of world runs on 220/240 volts, whereas industrial plants use 440 to 480 volts. This fact alone makes choosing the power transformer all the more selective.
Before choosing a power transformer there are few things to consider:
1. Determine the load size and load type
2. Primary voltage and frequency as well as secondary voltage and capacity
3. Determine the maximum load you can expect, this will help in determine the size of the power transformer
Power transformers require special accessories. They include off circuit tapping switches, transformer connectors, termination boxes, porcelain assemblies and wire harnesses. Wire harness or cable harness is one of the important accessories. Most of the electronic devices require special wiring. Wire harnesses are wiring configuration for these devices. Hence these can be used to transmit operational current or informational signals. Wire harnesses are especially used in Electronic, Computer & White Goods Industry.
Transportation of transformers for power plants needs special care. Because of their big size, they require to be transported in the same condition when the testing of completely assembled transformer had taken place. Until the final installation they should not absorb moisture from the atmosphere. For this reason core and coils of transformers are protected by dry air or dry nitrogen while transporting.