The most important factor when choosing a converter is to properly size your converter for your load. Not physical size but electrical size.
Example: If you need to run a 3HP metal chop saw you would need at least a 5HP phase converter. Or, if you have a 5HP metal shear you should probably go with a 7.5HP converter. Now this does not mean that a larger or smaller phase converter will not effectively run the equipment, it just means that this is the ideal converter for the application.
So why is proper sizing so important?
Your converter has been designed to best run a load of about 1/3 to 2/3 of your phase converters KW rating. By this we mean that the amount of capacitance and the balance of the three phases are configured such that they most resemble actual three phase power loaded at 1/3 to 2/3 of your rated converter power. It is at this load that the output power is within a couple percent of the input power.
Maintaining an output that is within a couple of percent of input power allows your three phase equipment to run at its best and draw the least amount of current. Running your equipment with converters generating out of phase voltages can be detrimental to your equipment's motor(s) and greatly shorten its life. Same goes for running three phase equipment from static phase converters which are designed to get your motor turning long enough so they run from two phases only.
Our customer's have reported that their current draw was reduced by as much as 80% when they replaced a static converter with our rotary converter.
The equipment I need to run has a 5HP motor, will a 5HP converter do the job?
Maybe.
The size of your machine's motor is just one factor for determining converter size. Real thing you need to know is how hard does the motor work to start your machine. Different types of equipment are harder to start and run than other types of equipment.
We developed a list of common three phase equipment with the power factor generally needed to start and run it. To determine recommended phase converter size multiple the power factor by your equipment's total wattage rating. Then, take that number and divide by 746, this will convert your wattage rating to HP. Your converter should be rated at this HP or larger.
Example: A table saw has a power factor of 1.5. Your table saw is 5HP or 3730 Watts. Watts x 1.5 = 5595 Watts; 5595 / 746 Watts = 7.5HP
Equipment LoadPower Factor
Air compressor--------------------------1.5
Air compressor 10HP+ ---------------1.75
Blower -----------------------------------1.4
Dishwasher ------------------------------1.2
Drill --------------------------------------1.25
Dryer -------------------------------------1.2
Glue Machine ---------------------------1.2
Grinder -----------------------------------1.5
Hoist -------------------------------------1.25
Heater ------------------------------------1.2
HVAC ------------------------------------1.5
HVAC Total 5HP+ ---------------------1.75
Iron Worker ------------------------------1.5
Injection Molding -----------------------1.5
Lathe --------------------------------------1.4
Meat Grinder -----------------------------1.25
Milling Machine -------------------------1.4
Metal Brake ------------------------------1.25
Metal Roll --------------------------------1.25
Metal Shear -------------------------------1.25
Mixer --------------------------------------1.4
Pump --------------------------------------1.5
Planer -------------------------------------1.5
Plasma Cutter ----------------------------1.2
Press ---------------------------------------1.5
Tire Balancer -----------------------------1.25
Sander -------------------------------------1.5
Saw Chop ---------------------------------1.5
Saw Table ---------------------------------1.5
Saw Band ---------------------------------1.25
Saw Radial Arm -------------------------1.25
Shaper -------------------------------------1.5
Washer ------------------------------------1.25
Welder ------------------------------------1.2
CNC equipment such as milling machines, lathes, routers and other voltage dependent machines require voltage balance within 5% or more. This means that your converter must produce voltages when measured L1- L2 and L2 - L3 and L1- L3. We only build CNC grade converters. All our converters are equipped with run capacitors on both legs of input power. This achieves the closet output power to true three phase as possible.
Why are the control panels for Elimia Phase Converters a lot bigger than others I've seen?
Because our converters have more "stuff" inside them.
As mentioned above all our converters are CNC grade and equipped with run capacitors. We are not relying on just the converter idler motor to generate the third leg of the three phase. We use capacitors along with the motor to generate an accurate third phase. We proudly display our voltage balance on our website with pictures of a three phase monitor during testing.
All our converters come with magnetic contactors. Contactors use a magnetic coil to hold electrical connections together while your converter is running. Magnetic contactors are better than spring loaded switches because they can provide much more contact to contact strength at the electrical connections. Plus, contactors are designed to open if at any time there is a power blink. And with our power blink safety feature your converter will not try to start back up after the power blink ends. Starting a converter with the load already on can damage the converter start capacitors.
We equip our converters with at least 125% of the starting capacitance needed to start the converter. Getting your converter started is probably it's most difficult task. By equipping our converters with extra starting capacitance we limit the stress on the capacitors which helps prevent breakdown.
Our converters utilize a unique electronic starting system which ensures that the starting capacitors are only engaged long enough to get your idler motor running. There are many methods that converter manufacturers use to get their idles running, some use shaft sensors, current relays, manual push buttons and probably more. We believe our method is the best and it allows us to equip Elimia Converters with options such as remote control start.
Some converter manufacturers are rated at 100% power, what does this mean?
It is theoretically impossible for a rotary phase converter to output 100% of its rated power. Any claims that a manufacturer makes is false.
So how come I am able to run a 5HP machine from my 5HP converter?
Simply, your 5HP machine does not require 100% of the motor rating to start and run.
It is very typical that you will never need all the power of your machine either running or starting. We have done test and successfully started 25HP equipment with a 3HP Elimia Converter. We only throw this out for discussion as we would never recommend it. In almost all situations your converter should be larger than the largest single load.
What size wire do I run to my converter?
Every installation is unique and requires an electrically knowledgeable person or a professional to properly install your converter.
Below are general minimum guideline for sizing wire and fusing supply power. Applies to wire runs less than 40 feet. Wire size should increase as distance between main power and your converter increases.
Probably the most important job when buying a converter is to properly size it for your equipment. Review the details below to help determine what size converter you need. As always, we are here to help.
