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It depends what you mean by an '11-kV transformer'; do you mean a primary transformer (33/11-kV transformer) or a distribution transformer (11-kV/400-230-V transformer). Differential protection IS offered on primary Transformers.
What else can I help you with?
Which relay is used to protect generators and motors?
differential protection relay
What is percentage bias relay?
This is basically a differential relay that contains an additional restraining coil with the operating coil connected at its midpoint used to prevent the unnecessary pick up of the relay.
What is the difference between diffrencial relay and a distance relay?
They're completely different, used for different applications (usually). A distance relay uses both current and voltage. A differential relay uses only current. A differential relay usually has harmonic restraint capability, while distance relays ideally track system frequency. Differential relays require fast operation, while distance relays may not be required to operate as quickly. Distance relays have more issues with operating for out of zone problems than differential relays. There are many more, but this gives an idea.
What is differential transformer protection?
The current input (primary) to a transformer is proportional to the output (secondary) current. Differential protection relays monitor these via current transformers (CT). The percentage of difference between primary and secondary can be adjusted. If it is over the seting the relay will trip the primaryand secondary feeder breakers. Thus indicating an inbalance between internal phasewindings and or shorts to earth.
Which types of relay is use in power transformer?
A 'power transformer' is a category of transformer used within electricity transmission and primary distribution systems. Relays are widely used with power transformers to provide various types of protection that will act to disconnect the transformer in the event of a fault. Examples of these relays include Buchholz relays, earth-fault relays, and differential relays. Relays are also used to operate a power transformer's automatic tap-changing mechanism in order to compensate for changes in load.
Which relay is used to protect generators and motors?
differential protection relay
Dear all what direct consequences can be from Current transformer on generator with respect to differential protection relay?
CT's are used as inputs to the differential. If the CT is bad, or it is not wired to the differential correctly, it will cause differential current to be seen by the relay, resulting in a trip.
Which instrument transformer mostly used in relays?
Both Current and Potential Transformers are used for relays according to the working of relay.
What is percentage bias relay?
This is basically a differential relay that contains an additional restraining coil with the operating coil connected at its midpoint used to prevent the unnecessary pick up of the relay.
What is the difference between diffrencial relay and a distance relay?
They're completely different, used for different applications (usually). A distance relay uses both current and voltage. A differential relay uses only current. A differential relay usually has harmonic restraint capability, while distance relays ideally track system frequency. Differential relays require fast operation, while distance relays may not be required to operate as quickly. Distance relays have more issues with operating for out of zone problems than differential relays. There are many more, but this gives an idea.
What is restricted earth fault protection and how is it provided?
A Restricted Earth Fault (REF) means an earth fault from a restricted/localized zone of a circuit. The term "REF protection method " means not to sense any earth faults outside this restricted zone. REF is a type of "unit protection" applied to transformers or generators and is more sensitive than the method known as differential protection. An REF relay works by measuring the actual current flowing to earth from the frame of the unit. If that current exceeds a certain preset maximum value of milliAmps (mA) then the relay will trip to cut off the power supply to the unit. Differential protection can also be used to protect the windings of a transformer by comparing the current in the power supply's neutral wire with the current in the phase wire: if the currents are equal then the differential protection relay will not operate; if there is a current imbalance then the differential protection relay operates. However, REF protection is also applied to transformers in order to detect ground faults on a given winding much more sensitively than differential protection can do.
Why buchholz relay is used in transformer have ratings more than 750kva?
Buchholz Relay is a special type of relay and its only used in transformers, and the main use of this relay is transmission and distribution systemAnswerA Buchholz relay is used between a transformer and its expansion tank. So they are only used (1) where there is an expansion tank and, (2) in substations, where the associated protection relays can be installed.
What is differential transformer protection?
The current input (primary) to a transformer is proportional to the output (secondary) current. Differential protection relays monitor these via current transformers (CT). The percentage of difference between primary and secondary can be adjusted. If it is over the seting the relay will trip the primaryand secondary feeder breakers. Thus indicating an inbalance between internal phasewindings and or shorts to earth.
What is metrosil?
Metrosil is a non linear resistor and used with high impedance differential protection.During an internal fault ,the voltage developed across the relay can be very high and the metrosil limits the voltage across the relay ,thus protecting the relay and the wiring from any damage
How much should a used Roland TD-11KV drum kit cost?
A nice, brand new, Roland TD-11KV drum kit (with mesh heads) should cost about $1600. Used can range anywhere from $1400-$1600
Where is Buchholz from?
If you are referring to a Buchholtz relay used to protect transformers, then it was named in honour of its inventor, Max Buchholtz, an engineer with the Prussian Electricity Supply Company, in Kassel, Germany.
What are the Application of electromagnetic relay?
1) protection of various ac and dc components 2)it can be used for differential protection 3)used as auxiliary relays in contact systems of protective relaying schemes
