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Earth Fault Protection, also known as Protective Earth Ground, also known as the Grounding Conductor, or more simply, just Ground, is a connection ultimately to a system of grounding rods that are driven into the earth. Typically, that ground connection starts at the utility power pole, where the neutral of the distribution transformer is grounded.
Neutral, also known as the Grounded Conductor (as opposed to the Grounding Conductor) is one of the conductors that transfer power to the load. It is grounded so that the other conductors, known as Hot, are never more than their specified voltage above ground, and also so that faults can trip the protective device (breaker or fuse) in the distribution panel.
Normally, Ground is connected to the enclosure of the load, such as the casing of a motor. If an insulation failure or other fault in the motor were to result in a short circuit to the casing, there would be a current path to ground, preventing the casing from become an electrocution hazard, and also ensuring that high current flows through the protective device, tripping it.
Sometimes, a fault to ground is not enough to trip the protective device, but it is enough to electrocute someone. The modern Ground Fault Current Interrupter (GFCI) breaker prevents this by comparing current on Hot against current on Neutral. By Kirchoff's current law, these two currents should be equal. If they are not, that means there is an alternate path, usually to Ground, and the GFCI trips.
Wiki User
∙ 14y ago
Wiki User
∙ 14y agoA fault between phase and ground.
A "fault" occurs as the result of the dielectric strength of an insulating medium fails. For overhead power lines, the insulating medium is typically air. The phase wires are spaced so far away from each other, and so far away from ground. This spacing is based on the "dielectric strength" of air, or how well air acts as an insulator/resists the flow of electricity.
If the distance between a phase wire and ground is decreased (the wood pole breaks), or the dielectric strength of air is compromised (someone starts a fire under a power line, or lightning strikes near by - both of these tend to lower the insulating capability of air) a line to ground fault is likely to occur.
Wiki User
∙ 9y agoAn earth fault is when an energized wire makes contact to a ground wire that is tied into a grounding rod, which is in the earths ground.
Wiki User
∙ 12y agoFailed conductor connection to earth
Wiki User
∙ 14y agoA fault line is where two plates meet.
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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.
Can an electrical short be caused a phase to a phase?
It could be a phase to phase, ph to neutral or earth fault. In single ph wiring ph to ph exhibits no short ckt faultAnswerYes, but you have got the terminology wrong. There is no such thing as 'phase-to-phase', the correct term being 'line-to-line'. So you can have a short circuit as a result of a line-to-line fault, a line-to-neutral fault, or a line-to-earth fault.
Why phase fault relays are having higher settings and more plug positions while earth fault relays are having lower settings and usually only two plug positions?
phase fault relay are having higher settings because the magnitude of phase fault currents are not so much higher as earth fault currents.hence in order to prevent any damage to the system,the earth faults should vanish as quickly as possible
What is a phase to phase fault?
Its is the condition when two different phases directly comes in contact with out any load or resistance.
3 types of faults?
Reverse faultNormal faultStrike-slip 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.
How is a IDMT relay used to give protection against a phase to earth fault a phase to phase fault on a feeder?
As with any IDMT relay the higher the fault current the quicker the trip time.
Can an electrical short be caused a phase to a phase?
It could be a phase to phase, ph to neutral or earth fault. In single ph wiring ph to ph exhibits no short ckt faultAnswerYes, but you have got the terminology wrong. There is no such thing as 'phase-to-phase', the correct term being 'line-to-line'. So you can have a short circuit as a result of a line-to-line fault, a line-to-neutral fault, or a line-to-earth fault.
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 phase fault relays are having higher settings and more plug positions while earth fault relays are having lower settings and usually only two plug positions?
phase fault relay are having higher settings because the magnitude of phase fault currents are not so much higher as earth fault currents.hence in order to prevent any damage to the system,the earth faults should vanish as quickly as possible
What is a disconnect installation fault?
I have never heard a fault type referred to as a "disconnect installation fault". In general there are a few types of faults - phase to ground or ground faults, phase to phase, phase to phase to ground, three phase, and three phase to ground. I'm guessing what you're referring to is a fault on a disconnect switch. Disconnects are used to isolate equipment. When a disconnect faults, it usually faults to ground.
How does an earth or ground fault affect 3 phase motors?
Three phase Delta motors can continue to operate when one phase has an earth (ground) fault, when the motors are powered from an ungrounded Delta or Wye (star) service. This feature can be helpful in agricultural and oil rig pumping because it allows the operation to continue until the affected motor can be replaced. Motors on a grounded service will trip and the pumping will stop immediately after one phase goes to ground.
What is earth fault?
The current of the earth fault.is appox 1.7amp please verify this with book concepts of physics by h.c. vermabecause i read it few year back and at present i don't have that bookA current that flows from phase conductors to earth or protective conductors etc from the point of an insulation breakdown.
What is a break in earth's crust?
A fault
What is a fault record?
fault records gives complete information about a fault,i. fault current magnitude,type of fault,fault phase details,etc.with time stamping.
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.
Which is most severe fault in power system?
Three phase fault is the most severe.
