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A CONTACTOR SHOULD NOT BE USED TO START A 3-PHASE MOTOR unless there is some sort of motor protection in series with it. You would need a 3-phase contactor and just connect each phase (1 wire) to each terminal of the line side of the contactor, and the 3 wires to the load side. 3 wires on the line side, and 3 wires on the load side.

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15y ago
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14y ago

In three phase you can, in single phase you can not use a 3 pole contactor. A single phase induction motor has two sets of coils and a centrifugal start switch. The start winding is in series with the start switch. The start winding provides a rotating magnetic field in one direction enabling the motor to start. The motor can be reversed by reversing the connections of either the start winding or the run winding but not both.

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14y ago

You need to buy a "phase converter" either rotary or stationary, such as Grainger #2MV47. Remember, when using phaseconverters, the three-phase motor will only run at 2/3 of its rated horsepower.

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12y ago

Just use one of the contacts instead of all three. Usually labeled as L1, L2, or L3.

In single phase, only one wire is used to make or break the circuit being controlled. Only one of the contacts need to be used for this purpose.

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10y ago

The physical internal windings between single phase and three phase motors makes this an impossibility. That being said money can make anything happen. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Other wise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start.

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9y ago

When using a three phase contactor on single phase, the three phase overload block must be used. The wiring of the contactor consists of taking L1 of the supply and connecting it to L1 of the contactor. The load is connected to T1 on the bottom of the overload block. L2 of the supply is taken to L2 of the contactor. Instead of connecting the T2 to the load, the conductor is taken back to the top and connected to the contactor in position L3. The other side of the load is connected to T3 on the bottom of the overload block. The overload block has three N.C. contacts, one for each leg of L1, L2 and L3. These three contacts are wires in series to the stop - start circuit. Years ago on old schematic diagrams these contacts used to be placed on the up stream side of the magnetic starter's coil. When the overloads tripped the voltage was left on the control circuit which was found to be dangerous for trouble shooting. Now the overload contacts are positions on the beginning of the start- stop circuit so that when a overload trips, the whole stop - start circuit becomes de energized.

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13y ago

The incoming single phase line is in series with all three contactor contacts. For example; Incoming supply line to the top of A phase contact. From the bottom of A phase contact to the top of B phase contact. From the bottom of B phase contact to the top of C phase contact. From the bottom of the C phase contact to the overload block and then to the motor connection box.

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9y ago

Use two of the lines, or one line to neutral. Make sure the voltage does not exceeded the listed voltage on the nameplate of the motor.

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11y ago

red.yellow.blue .neutral for black. green for earth

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Q: How do you use a 3 phase contactor in a single phase installation?
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Can a 240 volt single phase motor be supplied with one phase until the other phase is closed without harming the motor?

Not a good idea. Use a double pole single throw switch to start and stop the motor if motor HP is small. Use a motor contactor on larger HP motors.


How do you wire up a 208v single phase motor with micro switch?

if you are using the pressure switch to control a 3phase pump chances are it already has a magnetic starter and a single pole control circuit i have seen small 3phase air compressors with the contacts driven right off the diaphragm bigger ones usually have 110 volt controls i would be concerned about the current rating of the switch if you are trying to switch the motor directly there are many single phase compressors that run directly from the pressure switch


How do you wire 3 phase power to 1 phase power diagram?

In an emergency and for a short period of time you can single phase a three phase motor but the motor will be loud, have terrible power characteristics and depending upon the use will burn up rather quickly. You should never try to run this in other than a life threatening emergency situation, the motors are not designed for it. Normally you don't. <<>> A three phase motor will not start on single phase. If the motor was started on three phase and loses a phase, it will stay running at a lower percentage of efficiency. Now a days the motor protection will not let a three phase motor run in a single phasing condition. All three phase legs of the motor are monitored and in a single phase condition the other two legs of the motor draw a higher current. This higher current is sensed by the motor's overload heaters in the motor's contactor and take the motor off line by opening the motor contactor. Now to the question, any two legs of a three phase system in electrical terms is known as single phase. As long as the three phase voltage matches the voltage needed in the single phase power diagram it can be connected to operate single phase equipment.


How do you connected 3 phase motor to single phase power?

Use VFD to make 3 phase from single phase source.


Do televisions use single-phase or 3-phase power?

Answer 1: TV's use single-phase power. Answer 2: TV's use single phase power of 220 or 110 volts ac power depending on what part of the world you live in.


Can you use this switch for three phase incoming and single phase outgoing?

No A intermediate switch can not be used to change three phase to single phase.


How do you converter single phase to three phase?

you can use a rotophase


How can you use a 3 phase capacitor as a single phase capacitor?

Just use any two of the three terminals that are available, this will give you a single phase capacitor.


What is the Difference between a magnetic starter And a contactor?

Motor starter usually refers to the complete assembly, including enclosure, contactor, control transformer (if any), overloads, fuses (if any), etc. A contactor is really just an overgrown relay, and is just one component of a starter. That having been said, many folks use the two terms somewhat interchangably. So someone who says starter may mean contactor, and vise-versa. Go figure.


Can you use an AC contactor in the place of DC contactor?

No, you definitely cannot.


Why you use only single phase induction motor not other?

You would use a single-phase induction motor if the available electric power supply is a single-phase one. That applies to the average house or small business.


What will happen if you use phase to phase voltage for a single phase device?

Phase to phase, two wire is classed as single phase. If the voltage from the phase to phase match the device's operating voltage, then connecting the device will allow it to operate.