If you're working with three-phase equipment, such as table saws, drill presses and other fine cutting equipment, it may be helpful to know how to make a 3-phase converter. By using a three-phase power source—an electrical service transmitted as alternating current which reverse polarity every 60 times per second—you are capable of higher power transmission, along with a smooth wave form quality and a constant linear and balanced load. In simple terms, it is putting three waves of peak power where there is only one wave with common or single-phase power. Making a three-phase converter is rather simple. A rotary converter is made up of a simple three-phase motor connected to a single phase power supply.
To make a three-phase converter you will need:
- One three-phase motor that is twenty to 30 percent more powerful than the equipment you're planning on powering with the three-phase power
- One role of three strand Romex wire with a copper ground (you can ground the shells of the motors together if you wish, but is not necessary)
- In order to make a three-phase converter, find a three-phase motor that has a twenty to 30 percent higher horsepower rating then the largest piece of equipment in your shop. It must also be rated for 220 to 240 volts. This is your three-phase power generator or Idler.
- Take your 230 volt single-phase power supply and connect it to the first terminal and second terminal of your motor or the corresponding wires for the motor. In order to start the motor turning, take a rope around the pulley or shaft of the idler and pull. This motor will not start turning on its own and will need a little help.
Once the Idler is turning, take the three-phase power by wiring from your first and second terminals, as well as to the third terminal of the three-phase motor, to your shop equipment. Once you have done this, you will have a three-phase supply to your equipment.
You can make a three-phase converter with a three-phase motor. However, when you make a three-phase converter this way, there are some limitations. Because of the instability of the current provided, it might damage some of the more advanced equipment in the shop. It will also have less power to supply for the equipment, making a more stressful situation for equipment under heavy load. It can cause more noise, vibration and heat in both the equipment and the generator. This will cause a shorter life for most equipment involved.