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I'm guessing this is in reference to a restricted earth fault, and you want to know what the opposite is? Restricted earth fault protection is designed to operate for earth faults within a specific zone. Unrestricted protection will operate for faults "anywhere", as long as the pickup can be satisfied.

For example, REF (restricted earth fault) transformer protection looks for a small amount of neutral current, and if this exists, and the relay identifies this current as being within the zone of protection, the relay will trip. If it were unrestricted, the small amount of neutral current alone would be enough to cause a trip.

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How do you calculate 3 phase earth fault loop?

You can't have a three phase earth fault, you can have a phase to phase or a phase to earth fault. If you want the potential phase to earth fault current it will be your voltage times your impedance. If you want the phase to phase potential fault current then you should just double the above result.


Will earth fault affect batteries discharging in an equipment?

If one terminal of a battery is earthed (and, by this, we normally mean a 'chassis earth'), then an earth fault within the circuit supplied by the opposite terminal will result in the battery being discharged. The rate of discharge depends on the resistance of the earth fault.


What is earth fault loop impedance?

An earth-fault loop is the path taken by the fault current, when an earth-fault occurs within an electrical installation, and comprises a series circuit made up ofthe utility company tranformer's low-voltage winding,the utility company's distribution cable's line conductor,the consumer's line conductor to the point of an earth fault,the consumer's earthing conductor,and the resistance of the earth path back to the transformer.The combined opposition of this series circuit to the flow of fault current is termed the earth-fault loop impedance, expressed in ohms.


What is stator earth fault of generator?

its aproblem, thats what it is


Why neatural ground resistor using in 33kv transformer?

The function of a neutral earth resistor is to limit any fault current resulting from fault between a line conductor and earth.

Related Questions

What is an earth fault relay?

An earth fault relay is a relay that is activated by a fault current that flows from the power line to the earth. Earth fault relays are found in power distribution systems.


Earth fault relay and an overcurrent relay Methods to energise an earth fault relay?

Earth fault relay and an over current relay Methods to energies an earth fault relay with simulation diagram?


Is a fault is a crack in the Earth's crust?

Yes a fault is a crack in the Earth's crust


How do you calculate maximum earth fault current?

transformer max earth fault current


How does a standby earth fault relay work?

As per my openion standby earth fault relay work on zero impedance measurement, when earth fault occures than zero


What is the difference between balanced earth fault and restricted earth fault?

There is such a thing as a three phase to earth fault, so maybe this is what you mean by a "balanced earth fault". I don't believe any earth or ground currents would flow in this case. A restricted earth fault is a typical phase to earth fault, where the zone of protection is restricted to a specific area, such as around a transformer. "Restricted" is referring to the protection method, not what is actually going on with the currents and voltages.


What is the breaking point in the layers of earth is called?

A break in the Earth's surface might be called a chasm, a fissure, or a fault line.


What are the kinds of movements of the earth?

reverse fault, strike slip fault, and normal fault


How do you calculate 3 phase earth fault loop?

You can't have a three phase earth fault, you can have a phase to phase or a phase to earth fault. If you want the potential phase to earth fault current it will be your voltage times your impedance. If you want the phase to phase potential fault current then you should just double the above result.


What is a breaking point in layers of the earth?

That sounds like you are looking for the word "fault" or "fault line".


Break in Earth's rocks caused by stress?

Fault


Circuit diagram of stand by earth fault relay?

earth fault relay is similar like earth leakage ralay,but the 2nd one is more sensitiv.