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Calculation of restricted earth fault relay stabilizing resistor?
Wiki User
∙ 10y ago
Requirement of REF protection for 50KVA 11KV/.4KV transforemr
Wiki User
∙ 10y ago
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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.
How does cable sizing calculation gets affected by earth leakage protection?
Ground / earth protection will not impact cable sizing.
What is an Unrestricted Earth Fault?
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.
What is difference between neutral grounding reactor and neutral grounding resistor?
They both reduce earth fault levels by inserting impedance in the return path. A reactor is used when the earth fault level wanted is greater than about 25% of the phase fault current. This limit is due to over voltages experienced in arcing faults, the higher the reactor impedance the higher the potential overvoltage. With resistors lower fault levels are possible, but as the resistor has to dissipate all energy it will generally be more expensive and larger than a reactor.
What current does the input required to give an output on Lm741?
It depends on the shunt feedback resistor on the op-amp, for example with a 10k feedback resistor connecting the output to the inverting input, 1 mA input current gives 10 volts signal output. The input terminal stays near zero voltage because of the high open-loop gain of the op-amp, so the inverting input is termed a 'virtual earth'.
How designing stabilizing resistor in restricted earth fault relay?
To determine the value of Stabilizing resistor Rs = Vs/Is = If(Rct +2Rl)/Is Where, Rs = resistance value of the stabilizing resistor Vs = voltage at which the relay will operate Is = current flowing through the stabilizing resitor and the relay If = maximum secondary fault current magnitude Rct = internal resistance of the current transformer Rl = resistance of attached wire leads
What accounts for stabilizing effects of Earth's ocean?
The high latent heat of water.
What is the calculation from Jupiter to earth?
YES
What accounts for the stabilizing effects of Earth's oceans?
The high heat capacity of water helps to stabilize the Earth's temperature by absorbing and releasing heat slowly, preventing rapid temperature changes. Additionally, the ocean's circulation patterns distribute heat around the globe, helping to regulate climate and maintain relatively stable temperatures. The presence of large water bodies also influences weather patterns, reducing extremes in temperature and creating more moderate conditions.
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.
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.
What is the circulation calculation of the Earth and the Sun?
365 Days
How does the moon affect planets?
the moon creats earths tides! It also effects the planet by stabilizing the rotation of earth!
What Distance between electric earth point out building?
how long distance of electric earth cable , between point or manhole ,what calculation to make good earthing in building how long distance of electric earth cable , between point or manhole ,what calculation to make good earthing in building how long distance of electric earth cable , between point or manhole ,what calculation to make good earthing in building
What is the largest natural satellite orbiting the earth?
The largest natural satellite orbiting Earth is the Moon. It is about a quarter of the size of Earth and plays a key role in stabilizing our planet's rotation.
How does cable sizing calculation gets affected by earth leakage protection?
Ground / earth protection will not impact cable sizing.
Do tornadoes change the Earth's atmosphere?
The updraft of a tornado may help somewhat in stabilizing the atmopshere, but the parent thunderstorm normally would do that anyway.
