how to trouble shoot buck-boost transformer to change 1 phase to 3 phase.

[Etom]

I have a 2 buck-boost transformer that are used change 1 phase to 3 phase power. So that we can run a 3 phase motor off of 1 phase service power. The motor is not running it just hums.

After it comes out of the buck-boost transformers I have

• L1 TO L2 I have 218 volts
• L1-L3 I have 218 volts
• L2-L3 I have 0 volts.
• L1 to ground I have 111 volts
• L2 to Ground I have 218 volts
• L3 to Ground I have 218 volts

Is this normal for this kind of system? If not what could be my problem?

 

[gar]

160621-1646 EDT

I believe your question indicates you have little electrical background. A simple transformer arrangement won't convert a single phase power source to a three phase power source. The moderators will have to decide whether anyone should give you any advice. If you really only have a single phase power source, then it is not simple or cheap to power a three phase motor.

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[mpoulton]

As Gar says, you can't turn 1ph into 3ph with a transformer. This misunderstanding indicates that you have some very fundamental learning to do about what polyphase power is - and you need to have that knowledge before working with it. However, there actually is a fairly simple and inexpensive solution to run most small 3ph motors from a single phase supply. Many VFDs of 5hp and under are rated to accept 1ph input. If a VFD like this is suitable for your application, you can do it that way for a few hundred bucks.

 

[iwire]

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