Transformers = device which changes the voltage of an AC circuit to a higher or lower value.
Consists of an iron core two separate coils of wire are wound.
Coil is also called a winding.
Coil with higher number of turns (winds around the iron) has a higher voltage
Coil with fewer number of turns has a lower voltage.
Change depends on the direction the current runs, raising or lowering it as desired.
Changes voltage but practically no effect on total power in the circuit
Waste very little energy.
They generate heat due to the little waste that does occur
Transformers are used to step up voltage in order to transmit power over long distances without excessive losses.
like a signal booster
They also step down voltage to create a usable level such as used in households.
step up transformer = when used to increase voltage
step down transformer = when used to decrease voltage
Thermal rating = product of Voltage and Amperage or VA
Represents how much heat it can handle without melting or exploding.
1,000 VA = KVA
Insulation
small transformer = wire insulated by rubber or vinyl
Large transformer = insulated by a fluid which is resistant to the flow of electricity and capable of withstanding the high internal temperatures.
and Rapidly conducting heat away from the windings
Ventilation
They require proper ventilation to dissipate the heat generated
if not, a large transformer could explode, the cooling fluid is often toxic, turning to vapor or spraying on people would not be good.
Placement
Allowed either outside building or in a fireproof vault.
Noise
They create an audible hum noise and should be isolated
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