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To answer this question a voltage value must be given. Circuit breakers protect the conductors that feed the load. The lower the voltage value, the higher the current value, hence a larger the wire size is needed and therefore larger the breaker size for the circuit.
In reverse the higher the voltage value, the lower the current value, hence a smaller the wire size can be used therefore smaller the breaker size for the circuit.
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What size breaker is used for a 300 horsepower motor?
A breaker is based on the amount of current that the motor draws. This amperage should be taken off of the motors nameplate. In motors of a specific horsepower the amperage is proportional to the voltage the motor uses. Without the motors voltage this question can not be answered.
What is used in an electrical circuit to prevent a short circuit?
difference between p type and n type semiconducter materialAnswerInsulation is used to prevent a short current. To protect the circuit should a short-circuit fault occur is either a fuse or a circuit breaker.
Bus bar arrangements in sub station?
Burbars are the important elements in the electrical substation. Bus bars acts as nodal point in the substation which connects different incoming and outgoing circuits.Substations present in the power system performs various operations depends on the application such as stepping up the voltage, stepping down the voltage, high voltage transmission and switching stations to route the power to desired load center.Busbars in Substation:Busbars used in the substations are generally rectangular or circular cross section bars. These busbars can be either solid or hollow structures. Hollow circular cross section busbars are employes in EHV substations to reduce the corona effect.Switching Schemes:Switching schemes implies different methods employed to connect electrical circuits in the power system to transfer the electrical power in reliable manner. Switching schemes helps in deliver the electrical power to power system if any part of the system is faulty or under maintenance.Substations use different types of busbar arrangements or switching schemes depends upon the application, reliability of the supply and cost of installation. In every substations busbars plays a common role to connect different circuits. However switching is possible in the power system with the help of circuit breakers and isolators.Considerations for selection of busbar arrangement:Different types of busbar arrangements are employed based on the voltage, reliability of the supply, flexibility in transmitting power and cost. The other aspects considering in designing the busbars arrangements are:Simplicity in the designMaintenance of different elements without interruption in the power supplyFuture expansion feasibilityEconomical in cost of installation and operationDifferent busbar arrangements:Some of the switching schemes are busbar arrangements employed in the substations are listed below:Single Bus-bar arrangementDouble Main Bus-bar schemeMain and Transfer bus-bar schemeOne and half breaker schemeRing Main arrangement schemeSingle Bus-bar scheme:This is the simplest busbar scheme available which consists of single set of busbars connected to the generators, transformers and load feeders. All the feeders are connected by circuit breaker and set of isolators. This arrangement helps to remove the connecting elements (Generators, transformers, etc ) for maintenance by opening the circuit breaker contacts and further opening the isolators.Advantages:This busbar arrangement enjoys less cost of installationLess maintenancesimple operationDisadvantages:Fault on the busbar all the feeders connected to the busbars should be disconnectedwhen Busbar is under maintenance total supply and all feeders should be disconnectedLeast flexibility and reliabilitySee all 5 photosSingle busbar SchemeDouble Main Busbar Scheme:Normally in double main busbar scheme each circuit is connected to both the buses. In some cases half of the circuits can be connected and operated on each bus, in these cases bus or circuit breaker failure would cause loss to half of the circuits. In double main busbar arrangement one or two breakers can be provided for each circuit. Double main busbar and double breaker scheme provides high reliability in the case of fault or outage of one of the breaker.Advantages:Any circuit can be taken out of circuit for maintenanceFlexibility in connecting the feeder circuit to either of the busbarsDisadvantages:Most expensiveLoose circuits connected to busbar when fault occurs on the busbarDouble Busbar Single Breaker SchemeMain and Transfer Busbar SchemeMain and Transfer busbar scheme is similiar to single busbar arrangement with additional transfer bus connected. Tie circuit breaker is provided to tie both the main and transfer bus. During normal operation all the circuits are connected to the main bus. When circuit breaker connected to the circuit (transmission line) is required to trip for maintenance, tie circuit breaker connecting the main and transfer bus is closed. The relay protection for the circuits connected to the transfer bus is taken care by the tie circuit breaker.Advantages:Low initial costAny breaker can be taken of circuit for maintenanceDisadvantages:Requires one extra breaker for bus tieSwitching is somewhat complicated when breaker is under maintenanceMain and Transfer Busbar SchemeOne and Half breaker Busbar scheme:In One and half breaker scheme, two circuits are connected between the three circuit breakers. Hence One and Half breaker name was coined for this type of arrangement. Under normal operating conditions all the breakers are closed and both the busbars are energized. Any Circuit fault will trip two circuit breakers and no other circuit will be affected in this arrangement. When a busbar fault occur only breakers adjacent to busbars trips and no circuit will loose power. Two busbars can also be taken out of service with out affecting the power flow if the power source circuit ( alternator circuit) and receiving circuit (transmission line) available in the same bay.Advantages:Most flexible operation possibleHigh reliabilityBus failure will not remove any circuit from serviceDisadvantages:High costRelaying is somewhat complicated since the middle breaker must responsible for both the circuits on either direction and should operateone and Half Breaker SchemeRing busbar schemeIn this ring main busbar scheme arrangement, breakers are connected in ring and circuits are connected between the breakers. There will be same number of circuits as the number of breakers in the arrangement. During normal operation all the breakers are closed. During circuit fault two breakers connecting the circuit trips. During breaker maintenance the ring is broken but all the lines remain in service.Advantages:Low costFlexible operation for breaker maintenanceAny breaker can be taken out of service without interrupting loadPower can be fed from both the directionDisadvantages:Fault occur during maintenance will break the ringRelaying is complexBreaker failure during fault will trip one additional circuitRing Main Busbar Scheme
How would you change a fuse to a mini circuit breaker?
I imagine you are talking about an actual fuse box, as opposed to a breaker box. These are different. One has circular fuses, the other has breakers, which generally look like switches. If it is a fuse box, unscrew the circular fuse and replace it with a fuse of the same amperage. The amperage is noted somewhere on the top of the fuse facing you when you look at in the fuse box. It will either be 15A [A for Amps] or 20A if it is in a house. If it is a breaker, and it is just tripped, turn it all the way off, and switch it back on. If the breaker is actually bad, use should call an electrician.
What size breaker is needed for a 115v 60hZ 18.0FLA motor?
25 amps and it should be run through a contactor and motor over load set,you should set the over load to 5% above the motors full load current.And not your breaker should be a d curve type with 6ka rating.
Where is the circuit breaker for a hot water heater?
The owner's manual should specify the location of the internal circuit breaker, if your particular model has one. The breaker for the overall circuit should be in the breaker box with all the others.
How should a fuse or circuit breaker be used?
to protect the circuit
What should you do to the surge strip if the circuit breaker fails to reset?
You should replace the surge strip if the circuit breaker fails to reset.
How are Branch circuit protected?
Branch circuits are protected by the circuit breaker found in the electrical panel. Each circuit should have its one breaker. The breaker should be rated to protect the insulation of the wire, so you can determine the breaker size based on the circuit conductor size Example #14-2 should be protected by a 15 amp breaker
What is a Ampere Frame Rating of a Circuit Breaker?
The ampere frame rating for a circuit breaker designates how the circuit breaker should be configured. It also states the trip unit of the amp.
Should a fuse or a circuit breaker be connected in parallel to the circuit it is protecting?
No it should be in series.
Must wires be connected to breaker box?
It should be connected to circuit breaker. Circuit breaker will automatically discontinue the flow of electricity if it detects faulty condition.
What do I do if there is no circuit breaker for outdoor light?
If you have a light that is not being powered through a circuit breaker or fuse, you should call a qualified electrician to remove this circuit from the panel's bus and install a circuit breaker for it. Without an overcurrent protective device (circuit breaker or fuse) you have a potential fire hazard.
A parallel circuit breaker should be connected in a parallel to the circuit it's protecting?
For a circuit breaker to protect anything, it must be wired in series with whatever it is protecting.
What size circuit breaker should be used for dishwasher and disposal?
A 15 amp dedicated circuit breaker should be used for the dishwasher. The disposal can be wired to the general kitchen 15 amp circuit.
Circuit breaker trip cause smoke will homeowner insurance pay for it?
A circuit breaker does not "cause" smoke. A circuit breaker "breaks" a circuit when there is too much current, creating a hazardous condition for the wires that are connected to the circuit breaker. The circuit breaker PROTECTS you from electrical fire. Find the source of the smoke; what burned? If a circuit breaker tripped during the incident, it is usually caused by melting/burning wire insulation, either inside or outside of an appliance. If the insulation inside the walls of your house has burned/melted, it could be that the circuit breaker was too large for the wire or that the circuit breaker failed to shut off at the appropriate current load. If the circuit breaker failed, your insurance should help you. If an appliance overloaded the circuit, your insurance should help you. If someone connected an oversized circuit breaker, causing the wire to overheat, your insurance company may refuse to help you.
Explain whether or not a fuse or circuit breaker should be conected in parallel to the circuit is protecting?
If you were to connect a fuse or circuit breaker in parallel with a circuit, it would create a short circuit and immediately melt (fuse) or trip (circuit breaker). These devices must be connected in series with the load.
