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Supply Voltage

Many CNC/EDM require 208 or 220 volts AC, + or -10 percent. Unfortunately, the voltage of most single-phase supply lines is quite high, often 240 to 250 volts. When the single phase supply is above 230 volts and the CNC you are installing is not equipped with "taps" for higher or lower voltage, a transformer must be installed ahead of the converter to "buck," or lower the incoming voltage to a nominal level. GWM can furnish the proper transformer or recommend a correct size to be purchased from a local supplier. Buck/boost transformers are quite common, and will add or subtract voltage from the line in varying increments. Call GWM for help. You will need to know your single-phase voltage--measured with a digital voltmeter--the CNC spindle HP, and the nominal 3-phase voltage requirement of your machine to select a transformer. The "buck" transformer may add $150 to $550 to your installation.

For machines operating on non-standard voltages--380, 400 or 575 volts--consult GWM.

I hope you enjoyed reading this as much as I enjoyed writing it. And I hope you have added to your knowledge of understanding--and selecting--a phase converter. Thanks for listening.

Sincerely, Gary A. Werner