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Why were instrument of a transformer placed on a high voltage side in short circuit test?
Wiki User
∙ 11y ago
I assume "tension" in this question should be replaced with "voltage". Short circuit tests are often performed from the lower voltage side of the transformer, since a lower voltage source is then required to perform the test. Often times the test lab may not have a source that can output a high enough voltage to perform from the high voltage winding.
Wiki User
∙ 12y ago
Wiki User
∙ 11y agoSathiyama enaku theriyathu...
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How could you convert step up transformer into step down transformer?
Injecting power into the higher voltage winding of a transformer will make it act as a step down transformer; injecting power into the lower voltage winding will make it act as a step up transformer. A transformer can be used both ways.
You can use neutral to autotransformer?
Yes, but the transformer must have both the hot and neutral to work as designed. A auto-transformer is not a variable resistor that could reduce current/voltage by a change in the resistance which could be used in the hot and or neutral wire. An auto-transformer is designed to have the hot wire and neutral on each end of the winding with a variable tap in between. The resistance of the transformer and the inductance will effect the circuit to a limited way if placed in the neutral but this effect will not vary the voltage over the full range, the amount of voltage reduction will vary with the load's current draw, see ohms law. Neither a resistor or a auto-transformer connected in the neutral line only will increase the voltage above the level of the input like a correctly connected auto-transformer . Stanley
How does a current transformer work?
A current transformer is used in high voltage circuits where it is not possible to measure current directly. A CT is a step up transformer with only one turn in primary. There will be as many cores based on the purposes like metering, protection etc. The secondary of a CT should never be kept open circuited bcoz very high flux will be developed in the secondary and hence it may be damaged.
What is transformer tank?
The container the transformer core and windings are placed inside is the tank.
What components are placed in an electrical circuit to control the amount of resistance in circuit?
resistors, variable potentiometers
What position in the circuit is a fuse placed to protect a transformer?
In series to every phase winding of transformer.
What is the voltage obtained when a capacitor is placed in a dc circuit?
Eventually, the capacitor will charge to approximately the source voltage level. As this occurs, the current in the circuit will drop to near zero.
How could you convert step up transformer into step down transformer?
Injecting power into the higher voltage winding of a transformer will make it act as a step down transformer; injecting power into the lower voltage winding will make it act as a step up transformer. A transformer can be used both ways.
You can use neutral to autotransformer?
Yes, but the transformer must have both the hot and neutral to work as designed. A auto-transformer is not a variable resistor that could reduce current/voltage by a change in the resistance which could be used in the hot and or neutral wire. An auto-transformer is designed to have the hot wire and neutral on each end of the winding with a variable tap in between. The resistance of the transformer and the inductance will effect the circuit to a limited way if placed in the neutral but this effect will not vary the voltage over the full range, the amount of voltage reduction will vary with the load's current draw, see ohms law. Neither a resistor or a auto-transformer connected in the neutral line only will increase the voltage above the level of the input like a correctly connected auto-transformer . Stanley
What Is a core-core type transformer?
A 'core type' transformer core is one in which the primary windings and secondary windings are placed around each of the limbs, as opposed to a 'shell type' core, in which the two windings are placed across the centre core. A core-type core is a magnetic circuit equivalent to an electric series circuit, whereas a shell-type core is equivalent to an electric parallel circuit. This is better answered with a diagram, so I suggest that you do a search on the internet.
What diodes are called catching diodes?
It's a diode that is used to limit a voltage to some desired value. Importantly, it's used to limit a transient voltage or an alternative voltage. The simplest example is that diode placed across a relay's inductive coil. As current is cut off through the coil, a large induced voltage appears that can cause damage to the circuit. A diode can be placed in circuit to catch/damp the induced voltage.
Why lightning arrestor should be placed near transformer?
A lightning arrestor acts to reduce a voltage surge due to, for example, a lightning strike on a power line. This will protect the transformer from an over-voltage acting to break down its resistance. A lightning arrestor is connected between each line conductor and earth. Under normal voltage conditions, it acts as an insulator, but when a critical value of over-voltage is reached, it conducts -suppressing the voltage spike.
Why Current Transformer Placed Between Power Transformer and Breaker in Substation?
A current transformer is primarily used at the neutral point of a transformer for earth fault protection.A neutral current transformer will measure any ground fault current which will essentially flow from the star point of the transformer.A fault-detection device other devices is connected to the current transformer and, if the fault current exceeds a certain trigger value, the fault-detection device will give a trip command to an earth-fault relay to disconnect the supply of electricity to the transformer.Additional AnswerCurrent transformers are widely-used in substations to (a) allow the measurement of currents in the high-voltage lines, and (b) to operate protective relays. There are many different types of protective relays, and their function is to disconnect faults by (a) detecting them, and (b) tripping the appropriate circuit breaker(s).
How does a current transformer work?
A current transformer is used in high voltage circuits where it is not possible to measure current directly. A CT is a step up transformer with only one turn in primary. There will be as many cores based on the purposes like metering, protection etc. The secondary of a CT should never be kept open circuited bcoz very high flux will be developed in the secondary and hence it may be damaged.
Why is a voltmeter not placed inside the circuit?
The voltmeter is connected parallel to the circuit in order to measure the voltage drop across that circuit or sub-circuit. If you were to connect the volmeter series to the circuit, since it is a high impedance device, it would represent an effective open-circuit condition. You would see the voltage available to the circuit, but the circuit would not receive its intended current and it would not function. Contrast this with the ammeter, which you do place series to the circuit in order to measure the current flow through the circuit.
What is transformer tank?
The container the transformer core and windings are placed inside is the tank.
What is a current transformer and how can a current transformer be used to extend the range of a wattmeter?
A current transformer (CT) works just like any other transformer. It is important to note it is not referenced to ground. It reflects current flow, not phase to ground voltage, so it attempts to hold current constant, not voltage. There is usually one primary "winding": one large cable through a donut CT, and multiple secondary windings. If a secondary winding is shorted (a wire placed across its terminals), the voltage built up in the secondary will be equivalent to V = I*Z, where I is the secondary current, and Z is the impedance of the secondary winding, usually specified as some flat value plus so many ohms per winding. If too big of an impedance is placed on the secondary, a voltage will build up to the point that the donut CT saturates, resulting in an output wave that has a large amount of harmonics. If the CT is open circuit\'d, voltage will build up until it is high enough to arc over (usually where it should have been shorted). CT\'s can be damaged by open circuiting them, so don\'t do it.
