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Would have to know the current rating of the motor or each of the phases on the motor when running. 3 Phase motors usually use mucvh less current than their single phase counterparts. My son has a lot of 3 phase equipment in his shop and most of them run under 5 amps per leg. But you really need those specs from the motor.

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Q: What size feeder and breaker is needed for a 15 ton AC - 3 phase at 440 Volts?
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How do you come up with 277 volts?

The star point or wye voltage of a 480 volt three phase four wire system is 277 volts. The 480 voltage is divided by the sq root of 3 (for 3 phases). The sq root of 3 is 1.73. 480 volts/1.73 = 277 volts. The same formula is used on all three phase four wire systems. 208 volts /1.73 = 120 volts, 416 volts /1.73 = 240 volts, 600 volts / 1.73 = 347 volts.


How does 120 volts come from 208 volts?

208 is a three phase wye connection voltage. To obtain the each individual coil voltage the 208 is divided by 1.73 which equals to 120 volts. Hence you have 3 phase 208 voltage on the phase legs and 120 volts to the wye point which is grounded. This same formula is used on any 3 phase system. 600/347, 480/277, 208/120.


How many amps does a 2000 watt heater draw at 240 volts on each line?

For a single phase circuit, the equation you are looking for is I = W/E. Amps = Watts/Volts.


Three phase voltage in india?

It is 230V single phase and 440V in 3 phase system at 50 Hz.AnswerIf the single-phase voltage is 230 V, then the three-phase voltage must be 400 V, not 440 V. The line voltage is 1.732 times the phase voltage.


How is a 208 volt 3 phase electrical sub-panel wired?

Mark the phases red (phase) black (phase) and blue (phase) along with a white (neutral) and a ground (wire size depends on the main breaker amperage) the phases attach to the main breaker unless it is a breakerless panel attach the phases to the lugs on the bus bars top or bottom then connect the neutral to the neutral bus and the ground to the panel

Related questions

How many wires are used for a 460 volt circuit breaker?

If the load is single phase and the load requires 460 volts to operate, then two conductors will be needed and they will connect to a two pole breaker. If the load is three phase and the load requires 460 volts to operate, then three conductors will be needed and they will connected to a three pole breaker. The sizing of the wires will depend upon the current that is drawn by the loads.


Do you need a neutral to install 480 volts 3 phase heater?

If the heater is rated as a 3 phase 480 volt heater then a neutral is not needed. If the voltage stated is 277 volts three phase then a neutral is needed.


What size circuit breaker is used for a 10000 watt single phase cooler with 240 volts?

The equation for amperage is Amps = Watts/Volts = 10000/240 = 41.6 amps. It is not stated if this is a motor load or not. If it is a motor load then the feeder has to be rated at 125% x 41.6 = 52 amp wire. Also if it is a motor load then the breaker will have to be 250% x 41.6 = 104 amps. A 100 amp breaker will work and still be within the electrical code ruling. Otherwise for 41.6 amps a 50 amp breaker will be sufficient.


What is breaker size for 62.19 KW 3 phase?

A breaker protects the wire size of the feeder that is connected to it. The amperage of the load must be found. Without a voltage stated the amperage from the wattage given can not be calculated. The equation for amperage when the kw is given is A = kW x 1000/1.73 x volts x pf. The pf constant to use is .9.


Why am I only getting 120 volts from a 30 amp breaker that should be feeding 220 volts?

I assume you have a 30 amp two pole 220 volts breaker. Check the voltage source. If the source voltage is 220V, but out let voltage is 120 then the breaker must be faulty, a high resistance or partial open circuit could have caused the reduced voltage at the breaker outlet.


What size breaker for a 208 volt single phase motor that pulls 1.4 amps?

208 volts is not a common single phase voltage but you could just size your breaker to the capabilities of the conductor. 208 is normally a phase to phase voltage <<>> Many 230 volt motors can be connected to lower voltage supplies. These motors can be connected to supplies of 208 and 200 volts. The code requirement is that the 230 volt full load amperage of the motor be increased by 10% and 15% respectively for wire sizing and breaker selection. To answer the question you will need a two pole 15 amp breaker.


What size underground feeder wire is needed from a 400 amp breaker to a 125 amp panel box. The total distance is 100 feet?

1/0 <<>> This is a voltage drop question. A voltage and whether it is a single or three phase system must be provided to give an answer.


How do you calculate main breaker amps for 12 units 60 amps 3 phase volts?

This is a code question for a contractors licence. The explanation would take too long to type out. You have by no means given all of the information needed to give you an answer.


Are all large motors three-phase?

Yes, most large motors are three phase. Usually single phase motors only go up to 10 HP. Larger than this and the wire size and contactors used to control the motors becomes extreme. For example a single phase 10 HP motor on 115 volts draws 100 amps. The same single phase motor on 230 volts draws 50 amps. The same 10 HP motor on three phase system draws the following amperage; 230 volts is a 28 amp draw, 460 volts is a 14 amp draw and 575 volts is a 11 amp draw. As you can see the higher the voltage becomes, the smaller the wire feeder size is needed and much smaller size contactor can be used to control the motor.


3 phase panel double pole single throw breaker 2 wires from breaker going to lighted sign 120 volts each is this a 240 volt system or a 120 feeding 2 diff ballast in the sign?

In a three phase panel a double pole single throw breaker is definatly putting out 220v as two separate 110v circuits that are out of phase with each other. So from one leg to the other its 220v and from either leg to ground its 110v. By definition it is 220v but it could be used as separate 110v circuits as well. The only way to know how its actually being used would be to open up the sign and see if both circuits are tied into one ballast as 220v or if they split and go to differant ballasts then they are 110v circuits using a common disconnect means. Being that either way both circuits terminate in the same area they technically both require a double pole single throw breaker.


How many amps do you need to supply a 150kva transformer to get 118amps 480 volts?

Rephrase your question, as it doesn't make any sense. If the primary side of the transformer is 480 volts 3 phase, this transformer can be supplied from a breaker as big as 180 amps. If 480 volts 3 phase is your secondary then you can supply up to 180 amps to your loads.


How do you wire a roman weld transformer 120 kva 1 phase 440 volt from a 3 phase 480 delta-wye connection?

In a 480 volt wye connection you obtain two voltages, 277/480 volts. Any leg to grounded wye point will give you 277 volts. Between any of the legs to each other you will receive 480 volts. Any two legs of a three phase system is classified as single phase supply. From a 480 volt central distribution panel install a two pole breaker sized to the amperage shown on the welding machine. Be sure to use the input current and not the output current to find the correct feeder for the unit.