specifications

PHASE CONVERTERS

Either a static or a rotary phase converter can make it possible to run a three phase motor on single phase power. The static phase converter does not actually generate three phase power continuously as a rotary phase converter does, but only long enough for it to start. Then the motor is running only on two of the motor windings instead of three. This results in a loss of Hp by 1/3. If your motor starts & stop over five times per hour, a static converter should not be used, or if your motor is heavily loaded a static converter should not be used. Static converters should also not be used for any CNC/EDM applications, resistive loads or any equipment that requires all three legs of three phase power.

ROTARY PHASE CONVERTERS

Provide full three phase power but are more expensive to purchase then a static converter. They provide enough current and voltage to allow full rated horsepower of the motor being operated from the output of the converter. Static converters are only for operating one motor, but with a rotary converter of the right size, multiple motors can be operated at one time. Different applications require different sizing requirements of rotary converters, where as a static converter should match the exact motor being started. Its always best to let a phase converter technician size the converter for your application. For example a 5 Hp table saw, would use a different size rotary converter then a 5 Hp air compressor.

One important point on rotary converters is the rotary motor itself. Always purchase a rotary converter with a Heavy Duty Cast Iron Totally Enclosed Fan Cooled rotary motor. They are more durable, run cooler because of the amount of iron used in the motor and they provide more power then a rotary motor that is manufactured with rolled steel and its an open style motor. Open style rolled steel rotary motors are much cheaper for a converter manufacturer to purchase, they do not weigh very much so they are cheaper on shipping charges and they are quieter but they do not hold up and they do not provide the power of the TEFC rotary motors. These style motors allow moisture, dust and dirt and insects to enter the windings and bearings. Insects love the heat of the motors and will end up making a home inside the motor. The internal fan on the rotor, will suck dust in that accumulates on the windings and forms an insulation barrier that will not allow the winding to cool properly over time. If you take a look at all the woodworking and machine shop equipment that manufacturers provide, you will notice that they all use totally enclosed fan cooled motors on their equipment for the same reason. They are better motors.

DES-Co On-Demand Phase Trans-Verter

Uses Auto-Transformer Induction instead of a rotary motor to provide three phase power to applications that cycle on & off.     With a rotary converter,   the converter would always have to start first, come up to full rpm and then generate enough power to start the unit.   So, you have to start a rotary or let it run all the time, and then start your equipment, letting both the rotary converter and your equipment consume electricity.

With a Des-co On-Demand Phase Trans-Verter,   there is no current draw at all while in stand-by mode, no in-rush current as with a rotary converter. The in-rush current draw is only the load of the equipment being operated.

These Des-co style phase converters are used on air conditioning & refrigeration equipment, lift station pumps, oil field pumps and submersible pumps. Elevators are another application where starting and stopping doesn't make using a rotary converter feasible.    Des-co On-Demand Converters must be sized to your equipment, so always call first to assure proper sizing with this and all Des-co type converters.

CNC ROTARY PHASE CONVERTERS

are a different class of converter all together. You should always at the least, double the horsepower of the motor or equipment you are wanting to operate from the converter.   If you have a machine that instant reverses, has regenerative feedback and speed changes, you should make sure you size the cnc converter properly to be trouble free.    Another thing to remember that just because a phase converter has balanced voltages does not mean it is a cnc phase converter. There is more to it then just balanced voltages.    They also have to provide proper phase angle along with balanced voltage and current.     This again goes back to the style of rotary motor being used,   where a cast iron TEFC rotary motor has more power and will operate a more constant output when instant reversing or speed changing cnc equipment.
All Rotary Converters provide a Delta Three Phase Output. This is important when operating some newer CNC machines that have certain Fanuc or Siemens Controls that require a Wye Three Phase source.   In this case, the Delta output of the converter should be connected to an isolation transformer which will change the output of the converter to a Wye.
Also, it is not a good idea to operate any other equipment, other then the CNC equipment at the same time.   The feedback from the other equipment will sometimes cause the voltage to be unstable and you will end up getting an error reading on your controls and a shutdown.

INVERTERS--VFD DRIVES

Are solid state controls that can be used to vary the speed of an electric motor without losing any of its power. It can be used for soft starting epuipment and in a lot of applications, can be used as a phase converter.
Some CNC Machinery does not like Inverters as a phase converter because of the chopped DC that the inverter provides as the three phase output, but in some applications they work just fine.