How to connect an electric motor ?
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Three-phase motors are used mainly in the production.In this article we will talk about how to connect the motor 380 to 220 independently both in industrial and in the domestic environment.
Features of three-phase motors
Before describing the actual connection process, we note that for the three-phase motor requires a network with a voltage of 380V, which is usually indicated on the label on the unit.options there is also indicated for the correct operation and connectivity products.If the three-phase motor, you will see the words "380 / 220V», which means that this model can be applied in a single-phase network with a voltage of 220V.And the easiest way to connect a three-phase 380V motor is to connect it to the 220V network, simply by using an additional capacitor.
network In order to connect the three-phase electric motor to 220V network, you must:
- close the stator windings on a "triangle";
- connect the network phase at the output of any of the 3 windings (usually denoted in the chart as "A");
- connect the network zero at the output of another coil (usually referred to as "B");
- connect one end of the chain starting and operating capacitors at the output terminal of the third winding (usually referred to as "C");
- 2nd connected capacitors chain end of the windings to any "A" or "B".
Remember that the choice of coils and their connection sequence does not matter.If you have the basis to connect this circuit, be aware that you may need to further consider the presence of buttons, tearing the chain from the start capacitor at the end of the motor acceleration.Otherwise, in the stator windings can occur huge power surge that will cause the motor to overheat and lead him out of action.
Another nuance when connected to 220V three-phase electric motor is that the connection is always leads to power losses.Power loss can be from 30 to 50%, but it is not critical for domestic use.The resulting power would be enough to run the simple equipment, such as, for example, grinding, grinding or sawing machine.In domestic use three-phase motor is also designed for the simplest equipment.
Moreover, for the independent connection of a three-phase motor 320 to 220V is necessary to choose the starting and run capacitors.And to accomplish this, it is necessary, first of all, do the following.
- Thoroughly examine the parameters of its motor, determine its power correctly.
- Using formulas or tables to calculate the minimum operating capacity capacitors (1 kWh corresponds to about 70 uF capacitor capacitance).The formulas and tables can be found in directories of Electrical, or consult with a specialist.
- In order to gain the necessary working capacity, you need to perform a parallel connection of capacitors.
- To calculate the total capacity of the starting capacitor.Usually launcher capacity exceeds the working capacity of the capacitors in three times.
also add that to choose the best capacitor types: MBGO, MBGCH, OSH MBPG with an operating voltage of at least 300V.So in conclusion - a few additional tips.
important to know that after a long time off capacitors are quite dangerous, because the voltage is held at its outputs.In order not to accidentally touch the machine, it is worth making the fence and before you start working with a condenser, always producing his discharge.It should also be borne in mind that when working a long time with no load, motor, converted from 380 to 220V, can burn.
Also note that you can not connect the 3-phase motor 3 kW to household wiring to 220V.In this case, will "stand out" plugs or machines, and in the worst scenario, may even melt the insulation on the old wiring.
And finally recommend to reading one of our articles on this topic - How to connect the engine to 220.