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	Subject - 3 phase questions gigglez_0 On three phase power where you have like 240 volts three phase or 480 volts 3 phase does the 240 or 480 relate to the voltage measurement between 2 phases and nuetral or ground? Also on a 208/230 volt 3 phase motor, why are 2 voltages given. Is the power 208 volts between 2 phases or 230 volts between 2 phases or can the motor be wired for either voltage.....this question also applies to 208/230 460 volt motors. Can they be wired for 3 different voltages or is low voltage for both 208 volt service and 230 volt service Dave Nix The voltages are measured between two "hot" conductors. Example: 208, 230, 240, 460, 480 The motors are made with multiple "taps" where you can use the same motor at different locations and wire it according the the actual voltage available. Scott Vickrey In the case of the motor you mentioned labeled 208/230 460 volts. This motor can be wire for it's low voltage connection using 208 or 230 and for it's high voltage configuration using 460 volts. David Hyatt Both Scott and Dave are correct. The voltages you listed are line voltages, thats reading between line one and line two, line two and line three and so on. Not to be confused with phase voltage, that would be reading line 1 to neutral line 2 to neutral and so on. On 480 three phase wye, you will read 277 volts from line to neutral. On 208 three phase wye you will read 120 volts from line to neutral. This is called phase voltage. Hope this helps. gigglez_0 thanks for the replies..... But I am still confused as to why some motors are called 208/230 I have seen motors that are labled to operate on 208/230 and 460, am I correct in that these motors are operated on 460 volts when wired for high voltage and they operate on 208 or 230 volts when confiqured for low voltage set up. Its the 208/230 volt designation that is confusing me. Why is 208/230 listed as two seperate voltages with the slash mark in between instead of there being a motor for 208 volts and a seperate motor for 230 volts. I appreciate deeply any help in my getting straight on this subject. Dave Nix The voltage available at the building comes from a transformer somewhere. Depending on your area of the country or state, the utility company offers either a 480/277 volt and/or 208/120 volt 3 phase and/or a 230 volt 3 phase only and/or a 230/115 volt single phase supply. The motors are designed to be sold anywhere in the country so they don't have to manufacture two or three separate models of the same motor. Are you trying to figure out how to use this motor somewhere where the voltage is something different? David Hyatt They provide you will multiple taps that will work with all voltages listed as a convenience to the consumer. All these voltages will work on that motor, they just hook up to different wires. JimmyDee A motor that has the 208/240 lower voltage has a slightly larger wire size in the windings than a straight 240 volt lower voltage. This is because it will draw slightly more amperage at 208 volts than it will at 240 volts and because of this the motor manufacture will increase the wire size to prevent over heating. Its not a good idea to run a single voltage (240 volts for the lower voltage) at 208 volts fully loaded. Jim kingofmars well put Jimmydee. king