The Dark Side is... well... Dark

[gsmittle]

Finally got me new-to-me Jet table saw out of the back of the 'Burb. I took my first good look at the motor. It's not a three-horse like I assumed the model number meant, it's a five-horse. Three phase.

Looks like a solid-state phase converter will set me back about $200. Unless I can find a three-horse single-phase motor that will fit... I really don't want to replace the current motor--it's a huge monster.

On the positive side, the tilt and raise motions are smooth and even. Adjustments will wait until I have the top on, which will be after I get the phase converter, which will be after I get power to the shop, ... and on and on and on...

Wonder how much running three-phase to my shop would be???

g.

[Tom Slick]

If you live in a residential neighborhood 3ph it probably not available. to run that 5 hp motor on 220v 1ph with a phase converter you are going to need a 40 amp circuit. It might be cheaper to switch to a 3hp 1 ph motor.

[Hoover]

Three phase wiring is a commercial shop operation. You will be better off doing what Tom Slick recommends. Sorry.

[wardprobst]

I'm going to suggest using the converter rather than changing out the motor. You can find really decent converters these days and that motor will serve you well.
You can check about having three phase run in but as others have suggested it's not always easily available.
DP

[SARGE..g-47]

Forget having 3 phase run in as it is commercial. If you lived between two industrial settings and even could.. you could have bought a new saw for what it would cost to do so. A new 5 HP motor is probably over $400.

Your cheapest route as stated is converter and run the 40 A IMO.

Were you not told or did you not ask whether it was 3 phase or 1 phase before you purchased the saw? Just curious as what's done is done at this point.

Good luck...

[LCHIEN]

I don't know the actual costs involved, but:
1. Running 3 phase to the house is probably impossible or totally cost prohibitive as residential areas do not have 3-phase to the house, just to the substation so they will want a small fortune to run wiring to the house IF they will even consider it. After they run a 3Ph connection and install a three-phase meter, you will then have to spring for an electrician to put in a 3-Ph panel and distribution; that stuff is industrial and not going to be cheap either.
2. Running a phase converter is probably possible but you should get a converter rated for 5 HP. As Tom i think said that would be a 220V 40A circuit, and a big phase converter. I suppose you could consider buying a converter sized for 20A and put 20A breakers on the circuit and you saw could never use more than 3 HP or so... there might be some issues as the motor startup will still draw inrush current like a 5 HP motor... Still if you get a 5 HP converter then you will have a 5 HP saw which I can't imagine will ever bog down in anything you can physically lift onto the table.
3. Maybe cheaper than a 5 HP converter will be to buy a 3 HP motor - someone said this might be $400, you might offset the cost by trading in or reselling the working 5 HP 3 Phase motor, I imagine those are quite expensive too and would either have some trade-in or resale value. I'm sure you would have no use for it! You'll only have a 3-HP saw BUT you won't be cursing each time you step around the converter taking up space in your shop.

If you can get a 5 HP converter for $200 that's probably a good deal.

[LarryG]

As everyone has said, running three-phase power to your house is going to be cost-prohibitive. In most residential areas, pole-mount transformers are used. Typically you'll see only one transformer hanging on the pole. Three-phase power requires either two or three, depending on how much three-phase power is needed; and as Loring says, also the wiring back to wherever the nearest three-phase power is.

A 5HP single-phase motor at 240V needs a 60A circuit, so factor that into your decision. A 3HP motor (what I have) is generally more than plenty and needs only a 30A circuit.

I don't really know much about three-phase converters except that they exist, and that they provide a pseudo three-phase output. Sometimes a commercial shop will go out of business and someone will have the chance to buy all the equipment for a song -- the problem being that everything is three-phase (which is one reason everything is so cheap, because so few people can use three-phase equipment). In a case like that, where'd you'd be looking at buying several motors, a converter would make more sense. For a single tool, I think you might be better off just buying a new motor and making sure everything you buy in future is single-phase.

[gsmittle]

Forget having 3 phase run in as it is commercial. If you lived between two industrial settings and even could.. you could have bought a new saw for what it would cost to do so. A new 5 HP motor is probably over $400.

Your cheapest route as stated is converter and run the 40 A IMO.

Were you not told or did you not ask whether it was 3 phase or 1 phase before you purchased the saw? Just curious as what's done is done at this point.

Good luck...

Running the 3-phase was tongue in cheek--I live in a residential area and it's impossible unless I relocate my whole shop to a commercial area. No point in that for just a hobby.

I talked to a very knowledgable lady at a converter manufacturer, who said a heavy-duty solid-state converter rate for 4-8hp will give me about 2/3 the maximum horsepower of the saw. That's around 3 1/2 hp--good enough for anything I can lift onto the table. The converter needs to be heavy duty because the saw doesn't run continuously. Solid-state would run me a little over $200. The unit attaches to the side of the saw cabinet, so no tripping issue.

A rotary converter will give me the full 5 horses, but the cost is prohibitive. I do remember reading how to make your own somewhere on the 'net, but I'm not sure I want to risk burning down/blowing up the neighborhood.

I plan on having 100 amp service run to my shop in about a year, so 40 amps or so for the saw is doable.

The saw was free, and I didn't think to ask about the phase. We all know what happens when we assume.

More updates as I learn more.

g.

[LCHIEN]

...
I talked to a very knowledgable lady at a converter manufacturer, who said a heavy-duty solid-state converter rate for 4-8hp will give me about 2/3 the maximum horsepower of the saw. That's around 3 1/2 hp--good enough for anything I can lift onto the table. The converter needs to be heavy duty because the saw doesn't run continuously. Solid-state would run me a little over $200. The unit attaches to the side of the saw cabinet, so no tripping issue.
...


More updates as I learn more.

g.

Sounds like a good deal, 3.5 HP saw for $200
So how come the converter is not on the UPS truck yet?

And as a bonus, by swapping any two of the phases, the saw will run backwards and you can uncut previously sawed wood.

[JimD]

My old table saw had a 1 hp motor. It drew enough to trip a 15A 110 circuit - like the BT3100 will. Worked fine on a 20A circuit. Weighs a lot. The converter seems like the way to go but even a big 110V motor would work.

Is there any chance you could get Jet to swap you motors? If the saw is not new, then it probably is not an option. If it is new, it might be.

Jim

[cgallery]

You can find 5HP static phase converters on eBay for $75. New ones. I don't know if they are any good, but I'd certainly investigate to save $125.

[JR]

And as a bonus, by swapping any two of the phases, the saw will run backwards and you can uncut previously sawed wood.

Oh, don't I wish I had that feature...

[leehljp]

You live in St. Louis, a big enough area to find a motor rebuilder or resaler. Check them out and ask if they are willing to trade a 3 hp SP for your 5 HP 3P. You would be stepping down, but possible for no or little money to have to be exchanged.

[gsmittle]

Sounds like a good deal, 3.5 HP saw for $200
So how come the converter is not on the UPS truck yet?

And as a bonus, by swapping any two of the phases, the saw will run backwards and you can uncut previously sawed wood.

That's a nice feature, but the kickforward scares me...

Thanks for all the suggestions, guys. This is not a new saw. It's the old Jet blue, not the newer cream color.

I'll contact Jet--maybe they'll swap motors for a small charge. I'm Googling now for motor rebuilders.

g.

[momo44]

Another recommendation is to get a 3HP VFD which will not only convert 1 phase to 3 phase, but will give you the advantage of a soft start on the motor and braking on the stop.
They are less than $200 new:(click here) Plus, 3 phase motors are simpler and run smoother than 1 phase. Keep the motor and use a VFD.

Maury