The higher the current, the more heat is lost. To reduce these losses, the National Grid transmits electricity at a low current. This needs a high voltage. ... These high voltages are too dangerous to use in the home, so step-down transformers are used locally to reduce the voltage to safe levels .
What are step down transformers used for?
A step down transformer is designed to reduce electrical voltage . Its primary voltage is greater than the secondary voltage. This kind of transformer “steps down” the voltage applied to it. For instance, a step down transformer is needed to use a 110v product in a country with a 220v supply.
How are step down transformers used in the national grid?
In the National Grid, a step-up transformer is used to increase the voltage and reduce the current. ... Before reaching the end user, a step-down transformer , reduces the voltage from the transmission voltage to the safer voltage of 230 V for home use .
How do transformers make the National Grid more efficient?
The higher the current in a cable, the greater the energy transferred to the surroundings by heating. ... To reduce energy transfers to the environment, the National Grid uses step-up transformers to increase the voltage from power stations to thousands of volts, which lowers the current in the transmission cables.
Where are step up transformers used?
Step-up and step-down transformers are used in electricity distribution networks to change the voltage output from a power station (e.g. 25 kV) to that needed for high voltage transmission (e.g. 132 kV or 400 kV) and back down again for use in homes, factories and offices (e.g. 230 V).
What is the example of step down transformer?
The Step-down transformer diagram is shown below. For example, the range of voltage used by the power circuit is 230v to 110v , but in electrical devices, it is less like 16v. So to overcome this voltage issue, a step-down transformer is used so that it can be reduced from 230v to 110V and finally to 16v.
Can a step down transformer be reversed?
Conclusion: Standard step-down transformers may be reverse fed for step-up applications but there are several precautions that should be considered: ... Transformers with compensated windings will have output voltage 3-4% below nominal at no-load and 6-8% below nominal at full load.
Why is the national grid better than local power stations?
- Power stations can be based in less populous and remote areas of the country meaning pollution can be kept away from major cities.
- If one power station needs maintenance, consumers can still be supplied from others around the country.
Why do national grid overhead transmission cables use very high voltage?
The high transmission voltages are to reduce large losses from joule heating in the transmission cables . And the low voltages in the home are for reasons of safety.
Does a step-down transformer increase voltage?
A step-up transformer is one that increases voltage, whereas a step-down transformer decreases voltage . Assuming, as we have, that resistance is negligible, the electrical power output of a transformer equals its input.
What are the applications of a step up transformers and step down transformers?
Step-up and step-down transformers use electromagnetic induction to convert voltage between two circuits . We use both types in the distribution of power from supply stations to the end user, as well as to ensure that the appropriate voltage goes into a circuit on many personal devices.
How do you know if it is a step up or step down transformer?
If the input supply is given on the low voltage winding , then it becomes a step-up transformer. Alternately, if the input supply is provided on the high voltage winding, the transformer becomes a step-down one.
What appliances use step up transformers?
While this is done to make it suitable for general use, there are certain appliances like electrical motors, microwaves, X-ray machines etc . that require a high voltage to start. A step-up transformer is used to convert the existing power supply to the desired voltage.
How do you identify a step down transformer?
If input supply is given on the low voltage winding, then it becomes a step-up transformer. Alternately, if the input supply is provided on the high voltage winding , the transformer becomes a step-down one.
Why it is called step down transformer?
A transformer in which the output (secondary) voltage is less than its input (primary) voltage is called a step-down transformer. The number of turns on the primary of the transformer is greater than the turn on the secondary of the transformer, i.e., T 2 < T 1 .
What is step down transformer formula?
The currents I p and I s in the primary and secondary coils are related by I sIp=NpNs I s I p = N p N s . A step-up transformer increases voltage and decreases current, whereas a step-down transformer decreases voltage and increases current.
