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Earth fault relay and an overcurrent relay Methods to energise an earth fault relay?
Wiki User
∙ 11y ago
Earth fault relay and an over current relay Methods to energies an earth fault relay with simulation diagram
Wiki User
∙ 11y ago
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What ways do you make electricity that are bad for the earth?
Using NON RENEWABLE RESOURCES like Fossil Fuels, Petroleum Products & NUCLEAR Energy are methods that are harmful for Environment on EARTH and their usage should be reduced by generating Elelctricity through Renewable resources.
Explain the term floating earth in portable appliances?
A 'floating ground' (or 'floating earth'), in the context of your question, describes an appliance whose metal enclosure is ungrounded when it is designed to be grounded. This can happen, for example, when the supply cable's ground wire is not connected to the earth pin at a plug, or has become accidentally disconnected at the appliance.The purpose of grounding an appliance's metal enclosure is to provide a low-resistance path to earth in the event that an internal live conductor should accidentally make contact with that enclosure -thus causing the local overcurrent protective device to disconnect the appliance. If the ground wire becomes disconnected, then this protection will no longer apply, and the appliance becomes a shock hazard.
What is treated earth pit?
A treated earth pit is an earth pit made according to the IS and has dis-connectible flanged connection to the earthing mat. This earth pit is used for measuring individual earth pit resistances.
Why should a earthing circuit have low resistance?
The purpose of an earthing (protective) conductor in a residential installation is to allow sufficient fault current to flow, in the event of an earth fault, to enable the operation of the circuit's overcurrent protection device (fuse or circuit breaker), so its resistance must be sufficiently low to allow this to happen.
What is residual earth fault protection?
Earth fault protection is protection based on ground, or zero sequence current. If current is coming up from the ground (or going down to the ground), this protection should operate. Residual usually refers to 3*I0, which is the same as the ground current, and is the vector sum of the current in all three phases. This can be measured by connected all three phase CTs in wye, and placing a single phase overcurrent relay in the wye path to ground.
Give the limitations of scientific methods in earth science?
Problems Using Scientific Methods In Agriculture
To study earth's interior geologists often rely on indirect methods such as evidence from fossils?
To study earth's interior, geologist often rely on indirect methods such as evidence from seismic waves, not fossils.
What hapend when earth is not connected in electrical circuits?
The main purpose of earthing electrical circuits is to provide a low-impedance route back to the substation transformer which, in the event of an earth-fault will allow sufficient fault current to flow in order to operate a circuit's overcurrent protection.
How does the standby earth fault scheme work?
Restricted earth fault protection is used to protect a specific zone, and should not trip for a fault outside of that zone (usually limited to a transformer, and possibly extending to lowside, highside, and tertiary breakers). Stand by earth fault protection is a term I am not very familiar with, but I believe this would be protection that is meant for a specific zone as backup, and can operate for faults outside of this zone. An example might be a highside time overcurrent relay set looking into a transformer, where the transformer is protected by a differential (primary protection), and there is a lowside feeder with relays (primary protection). The highside overcurrent acts as a backup (secondary protection) for the transformer and the feeder, and is delayed due to the nature of a time overcurrent relay.
What method of energy from the sun reaches the earth by which method or methods?
in the form of photons
What are the methods for stormwater purification?
It goes threw earth then comes out the other side
Methods used to investigate the planets?
Many methods and tools are used to investigate planets both from Earth and in space. Telescopes, physics, fly-by missions and Mars and Moon landing equipment are all very useful in studying things outside Earth.
What are the most common a variety of methods Geographers use to study the use of space on earth?
GIS (:!
What are the methods to know the interior of the earth?
Geologists have discovered a lot about the interior composition of the Earth by studying 'S' and 'P' seismic waves. For example, they learned that Earth has a liquid outer core when they noticed that 'S' waves didn't come out on the other side of Earth because they are unable to travel through liquids.
How have geologists learned about earth's structure?
they have used two methods direct and indirect. seismic waves are the forces produced when earthquakes occur.from rocks from deep inside earth they can give inferences about conditions deep inside earth. they also record the seismic waves and record how dast they travel through Earth this is an indirect method
Differetiate between solid earthing and ELCB?
ELCB is the connection to the direct earth path using protective device.while solid earthing is without protective device.A form of ELCB should be installed when direct earth path of low enough impendance can not be obtained.
Is the study of the earth's surface and how people use it?
Others study the impact of human activity on Earth's environment, and design methods to protect the planet. Some use their knowledge about Earth processes such as volcanoes, earthquakes, and hurricanes to plan communities that will not expose people to these dangerous events.
