The age old question. 3phase down to single

[Sam Beagle]

I know this has been covered here a few times. But here's my spin on it.
I'm building my dream shop. Everything I have now is single phase. But today I got an opportunity to buy some really nice 3 phase high end equip that I need to finish my tool purchases.

Here are my questions
1. Can a single and 3 phase shop coincide.
2. Are the converters safe
3. Does it economically make sense to go this route.
4 do you need a converter on every piece.
Thanks again, and I really enjoy this site. I'm in the process of reading all the pages of posts over the year. Right now I'm on 123 pages back. I love to learn. Sam

[Michael Mahan]

Ask the woodman is doing series on up-grading his Hitachi Bandsaw to 3 phase motor & he's using a 'New" Mitsubishi 'Majix Box' a variable frequency drive to deliver the 3 phase power in his single phase shop

http://www.youtube.com/watch?v=Jbvu6bq1Etc

[Matt Day]

1. Yes
2. Yes
3. Yes
4. No. You could use a VFD on each machine, or use an RPC to power multiple machines. You just need to size the RPC to the machines you have. There is a TON of information about this here on SMC.

[Keith Hankins]

I've got both in my shop no issues what so ever. If you get a know brand like American Rotary (American made) then not a big deal really. You just need to decide what size you want to go with. I bought a 10hp unit that will drive up to 7.5hp 3ph motor. I've got two 3 phased pieces and will get more. The big nice industrial equip is less expensive and better equipment.`

Forgot to mention that when dealing with 3 phase equip some is 480 3 phase and some 220 three phase. It will make a diff in whats required.

[robert morrison]

1.Yes
2.Yes
3.Yes
4.No You can use a VFD on more than one machine. Single phase power from panel into the VFD. Three phase power from VFD to recepacle box. Diffrent 3 phase machiney can be plugged into the same receptacle, but only one at a time. Obviously the VFD has to be rated for handeling the largest hp machine that you want to use it on. This is economical for up to 3hp machinery. Excells where you want variable speeds at the touch of a button. Currently I have this setup for a drill press and lathe that are back to back. A 2hp 3 phase Powermatic model 26 shaper was recently moved to the end of these two mchines, and will use the same outlet. The RPC is more cost effective for handeling machinery over 3 hp.

my .02

[Brian Ross]

I am a big fan of American Rotary. Excellent product and true 24/7 service. This comes into play if you get an electrician that does not understand how they work. I have two 20 hp units in my shop and one has been running for 8 years without a burp and the other 6.

Brian

[Ethan Melad]

I also have both in my shop - shaper and jointer are 3 phase on a 7.5hp (or maybe 10hp..?) rotary converter, most other machines are 220, some 110. No problems for me, but I agree that its very helpful if your electrician knows something about phase conversion. Mine didn't, and so I basically had to provide him with info/diagrams, etc. and it was an unnecessary hassle.

[Rich Riddle]

1.Yes
2.Yes
3.Yes
4.No You can use a VFD on more than one machine. Single phase power from panel into the VFD. Three phase power from VFD to receptacle box. Different 3 phase machinery can be plugged into the same receptacle, but only one at a time. Obviously the VFD has to be rated for handling the largest hp machine that you want to use it on. This is economical for up to 3hp machinery. Excels where you want variable speeds at the touch of a button. Currently I have this setup for a drill press and lathe that are back to back. A 2hp 3 phase Powermatic model 26 shaper was recently moved to the end of these two machines, and will use the same outlet. The RPC is more cost effective for handling machinery over 3 hp.

my .02
I agree with this with one caution. If you run more than one machine using the same variable frequency drive (VFD), you really should readjust the VFD to each machine on which you utilize it. That's why below a certain threshold (usually 3 horse power motors), many people simple purchase a VFD for each machine. Low horse power VFD units prove far less expensive than larger models.

I use both a VFD and three-phase rotary phase converter (RPC) in the shop. Depends on your needs.

[Ed Aumiller]

Some VFD's will burn up without a load on them when they are plugged in...
Recommend a VFD per unit hard wired into the machine..

RPC's do not have this problem...

[Peter Quinn]

1.Yes
2.Yes
3.Yes
4.No You can use a VFD on more than one machine. Single phase power from panel into the VFD. Three phase power from VFD to receptacle box. Diffrent 3 phase machiney can be plugged into the same receptacle, but only one at a time. Obviously the VFD has to be rated for handeling the largest hp machine that you want to use it on. This is economical for up to 3hp machinery. Excells where you want variable speeds at the touch of a button. Currently I have this setup for a drill press and lathe that are back to back. A 2hp 3 phase Powermatic model 26 shaper was recently moved to the end of these two mchines, and will use the same outlet. The RPC is more cost effective for handeling machinery over 3 hp.

my .02

Ditto. I have a 10HP American Rotary phase convertor, all of the machines I run with it are well over the 3 hp threshold above which VFD's get expensive. I have one 3 phase circuit powered by the convertor, it feeds twist lock receptacles just like the 220V single phase in my shop, only difference is I have to turn on the convertor first and flip a knife switch to energize the receptacles. Once you get into 3 phase machines, its hard to turn back to consumer grade. I like the RPC because I can run multiple machines simultaneously without issue, not of my machines benefit from the speed control associated with VFD's presently.

[Loren Woirhaye]

I use a 10hp rotary unit now. I had a 5hp but I acquired a machine with a 7.5hp motor and needed to upgrade to run the thing. A lot of 3 phase machines have complex wiring and switch setups and would not be able to work as designed using a VFD. Boring machines and wide belt sanders are not likely to be compatible with VFD use.

[Chris Parks]

I agree with this with one caution. If you run more than one machine using the same variable frequency drive (VFD), you really should readjust the VFD to each machine on which you utilize it. That's why below a certain threshold (usually 3 horse power motors), many people simple purchase a VFD for each machine. Low horse power VFD units prove far less expensive than larger models.

I use both a VFD and three-phase rotary phase converter (RPC) in the shop. Depends on your needs.

The VFD's I was supplying to customers have 10 different profiles in them so each machine can be programmed with its own profile. I was getting them out of China straight from the manufacturer.