Thread: Fans: 3phase to 1phase conversion

The 3 phase motors cannot be converted to single phase. Your options are

1: finding a suitable single phase motor of the correct frame size and h.p., and doing the conversion.

2: Buying or making a rotary phase converter from a scrap motor and ebay parts for a couple of hundred. Run through a 30A single phase breaker and a disconnect-you'll be able to make enough 3 phase for nearly 10 h.p.

3. Depending on the h.p. rating, buy a surplus VFD (variable frequency drive). They can all convert single phase to 3 phase. You need to de-rate the VFD by 1.4 for converting single to three, but you gain the variable speed feature, which might be usefull for fans. The price of these increases rapidly with h.p., I think $150.00/hp on ebay. Triple that for retail.

I have a rotary without a transformer, so I make 240v three phase. With this set-up I can use most industrial machines. With a buck-boost transformer, I could step-up the voltage to 440, which is the standard.

Greg

Thanks a lot for that very thorough and helpful reply Greg. Looks like the outfit's for sale, as my electrical skills don't extend much further than very basic rewiring.

Any offers anyone?