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There will a only one phase on Home Electricity.
AnswerThere is no such thing as a phase-to-phase-to-ground fault'; the correct term is 'line-to-line-to-ground fault. It occurs when two or more line conductors make contact with each other and to ground; for example, when a JCB accidentally cuts through a three-phase cable.
Wiki User
∙ 10y ago
Wiki User
∙ 14y agoThis is where there is a path for electricity between one "hot" wire and the ground. This is also called a ground fault.
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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 are symmetrical faults?
A three-phase symmetrical fault exists when all three line conductors are short-circuited, sometimes to earth (ground). An unsymmetrical fault occurs when only one or two of the three lines are involved.
What is the GFCI?
A "GFCI" is a ground fault circuit interrupter. For more information see the link below.
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.
Is transmission voltage a phase to phase voltage or a phase to ground voltage?
Phase to Phase voltageCorrection to the above answer:There is no such thing as a 'phase-to-phase' or 'phase-to-ground' voltage. The correct terms are 'line-to-line' (or 'line voltage') and 'line-to-ground' (or 'phase voltage'). Transmission-line voltages are line-to-line (or 'line') voltages.
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.
What are the types of faults in ehv transmission lines?
The three types are Line to ground faults line to line fault double line to ground fault three phase line to ground fault
How can you have a ground fault protection in a 3 phase 3W system?
3 phase ground fault detection on a 3 phase system requires that the vector summation of all three phase currents be measured. The vector sum of these currents should equal zero, or nearly zero for a balanced system. If a ground fault exists, then the vector sum will not equal zero. This condition must be validated using i2t techniques in order to eliminate false trips.
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 are the types of transmission line faults?
these are the faults that occur in transmission line: 1. line to line fault 2. line to ground fault-this is the most common fault that occurs in tr. line(75%) 3. double line to ground fault 4. triple line to ground (or) 3 phase fault- this is the most serious and dangerous fault that occurs in transmission line.(but rarely occurs)
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 are symmetrical faults?
A three-phase symmetrical fault exists when all three line conductors are short-circuited, sometimes to earth (ground). An unsymmetrical fault occurs when only one or two of the three lines are involved.
Why a 3 phase fault is more severe than other fault in transmission line?
It isn't necessarily (depending on your perspective). A three phase fault is a severe duty on generators, because all three phases are shorted. In solidly grounded systems a phase to ground fault could result in higher magnitude currents, which would be more difficult for a breaker to interrupt (so from the breaker's perspective, this would be more severe).
Why short circuit and accidental ground is the most dangerous faults?
These are the most dangerous faults because you will be dealing with very high fault levels. Phase to phase will have very little to limit the impedance of the fault current. And phase to ground faults can be high since most systems are solidly grounded. Arching faults and faults through an impedance will be lower and cause less electrical and mechanical stress on the system.
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.
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.
What is the GFCI?
A "GFCI" is a ground fault circuit interrupter. For more information see the link below.
