Recommendation? speed control for 3 phase motor

H

HSC ///

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Nov 7, 2012
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the new place I moved into has 3 phase wiring,
so I'll order a 3 phase motor (for a disc grinder) that I would normally wire up with a 110 VFD.

now I can plug directly into a 3phase outlet, so what do you suggest for an inexpensive speed control and reverse option controller?

I see several options available online, looking for your experienced suggestion

thanks
 
I have never used bought a 3ph input VFD befor but I would be half tempted to just get a normal vfd that can run off single phase. Unless you plan on being in the new shop for ever. 3ph is rare and you are a lucky bastard lol
 
VFD is still the only practical way to control a motor the way you want.
Shop around & look at their ’specs. Many VFDs can be powered three phase or single.
You also need to know what voltage your 3Ø service is.
 
One thing to consider about going 3 ph - the place you've just leased is 3 ph and that is the way to go for sure....... BUT - what about 10 yr down the road? Will you always be in a place that has 3 ph? While 3 ph is better (we're told that anyway), single phase 220 works just fine. Of course, the only thing that would be changed is the VFD, and many of those will operate on 3 ph or single phase either one, so maybe it's a mute point.

Looking thru the thread where you're "showing off" your new place - that's NICE!!!! Good looking 3 ph panel.
 
just buy a VFD that is rated for 1 and 3 phase if the voltage you have is 240. the all the 440 vfds i have seen are 3 phase only.
 
Wait? You guys(in America I'm guessing?) don't have three-phase wiring everywhere?

And aside from that: VFD definitely, maybe even go the extra mile with speed control
 
SV-97 said:
Wait? You guys(in America I'm guessing?) don't have three-phase wiring everywhere?

And aside from that: VFD definitely, maybe even go the extra mile with speed control
Click to expand...

3 phase is available in most or all cities but very few buildings, unless they are industrial buildings have 3 phase service.

Very very few of us have it available in rural areas due to the increased cost of running a third wire for distribution.
 
SV-97 said:
Wait? You guys(in America I'm guessing?) don't have three-phase wiring everywhere?

And aside from that: VFD definitely, maybe even go the extra mile with speed control
Click to expand...

America is odd in many ways...
Rural property excepted. 3Ø is available at most commercial properties, but often older buildings were not wired to accept it. Residential property basically never.

Sadly its the price of being self proclaimed leaders of the free world.
 
I'd keep an eye out on eBay or any local surplus shops. Obviously you want to be mindful of the specs, but I see 3ph input/output VFDs on the used market going for next to nothing all the time. If you do end up moving to a single phase shop in the future, you could always build a RPC, but for what used/surplus 3phase VFDs go for now days, you likely won't be out too much $$ to begin with.
 
What is the expected benefit of running a three phase drive, only while you have three phase power?

I've not seen an increase in my electric bill with the KBAC I use next to my TECO 1 Hp, I will however, never run an electric heater again in California. ABB will let you run some of their drives on both, but in single phase service it has to be "overated" (translate to, buy a bigger VFD than you actually need) You can still use single phase input drives now and in the future.
 
ron_m80 said:
What is the expected benefit of running a three phase drive, only while you have three phase power?

I've not seen an increase in my electric bill with the KBAC I use next to my TECO 1 Hp, I will however, never run an electric heater again in California. ABB will let you run some of their drives on both, but in single phase service it has to be "overated" (translate to, buy a bigger VFD than you actually need) You can still use single phase input drives now and in the future.
Click to expand...

I guess in this case it appears from this discussion that there is no benefit,
I just thought I would make use of the fabulous power I have available and was hoping a 3 phase speed controller would be less costly
 
HSC /// said:
I guess in this case it appears from this discussion that there is no benefit,
I just thought I would make use of the fabulous power I have available and was hoping a 3 phase speed controller would be less costly
Click to expand...

Like Jesenius said above, if you've got 3 ph you can run smaller wire, lower amps per phase. And I imagine if your equipment is anything like mine, much of it doesn't require speed control and is already meant for 3 phase. While the advantage for running a knife grinder or variable speed disc may be low, now any mill, drill, surface grinder, or welder you find at any industrial auction is plug and play (the majority of it can be wired 240 or 480).

While we all tout converting single phase to 3 phase via VFD and how it comes with the added bonus of speed control, it's not always ideal. Using a VFD to control your milling machines speed may be really convenient, but will not provide the same level of performance running it from 3 phase without a VFD will, especially at low RPM. When I get a phase converter going I will pull the VFD off of my milling machine and use it the way it was intended, because having the ability to instantly reverse and high torque at low RPM is more valuable to me than being able to dial spindle speed easily.
 
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