What do you mean by instrument transformers, Electrical Engineering

Assignment Help:

Q. What do you mean by Instrument transformers?

These are generally of two types, potential transformers (PTs) and current transformers (CTs). They are designed in such a way that the former may be regarded as having an ideal potential ratio, whereas the latter has an ideal current ratio. The accuracy ofmeasurement is quite important for ITs that are commonly used in ac circuits to supply instruments, protective relays, and control devices.

PTs are employed to step down the voltage to a suitable level, whereas CTs (connected in series with the line) are used to step down the current for metering purposes. Often the primary of a CT is not an integral part of the transformer itself, but is a part of the line whose current is being measured. In addition to providing a desirable low current in the metering circuit, the CT isolates the meter from the line, which may be at a high potential. Note that the secondary terminals of a CT should never be open-circuited under load. The student is encouraged to reason and justify this precaution. One of the most useful instruments for measuring currents in the ampere range is the clip-on ammeter combining the CT with one-turn primary and the measurement functions.


Related Discussions:- What do you mean by instrument transformers

What are the predefined interrupts in 8086, What are the predefined interru...

What are the predefined interrupts in 8086? The predefined interrupts are, DIVISION BY ZERO (type 0) Interrupt. SINGLE STEP (type 1) Interrupt. NONMASKABLE (ty

Change management in power distribution, Change Management in Power Distrib...

Change Management in Power Distribution: Organisational change might be described as an organisation-wide effort to augment the effectiveness of an organisation through str

Explain the significance of v number, Explain the significance of V number....

Explain the significance of V number. Ans: V number or V parameter or normalized cutoff frequency is one of the parameter which is used to calculate the maximum number o

Dsp, A pure sine wave with a frequency of 100Hz is sampled at 150Hz. At whi...

A pure sine wave with a frequency of 100Hz is sampled at 150Hz. At which one of the following frequencies would you expect an alias?

Transformer, how back emf is produced in transformer?

how back emf is produced in transformer?

Oscillator, how to design colpitts oscillator?

how to design colpitts oscillator?

Dc motor, You have been given a DC motor to characterize. What three measu...

You have been given a DC motor to characterize. What three measurements are required in order to develop the torque-speed curve and the acceleration curve for the unloaded motor?

Energy stored in a magnetic field , Energy stored in a magnetic field ...

Energy stored in a magnetic field Consider a circuit consisting of a voltage supply,  switch,  resistor  and  a  coil  of  N turns wound on a toroid of length l, all in series

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd