A gloat and a regret

[radhak]

Thanks Jon - been searching for that manual but could not find it. Amazing that for all of Google's power, there are things it can't dig up! How did you find it?

UC, so I guess if it is a 3 phase I might as well forget about it?

What I don't understand is, if it comes single phase out-of-the-box, why'd anybody convert it to 3phase?

And how do I confirm it? If somebody has rigged it, it would not have a label saying so - would the electric wiring (at the outlet) be different, or marked '3 phase' or something? I do plan to go there tomorrow, but not sure the seller would be able to help much - he sounded like he was not sure today.

[OpaDC]

Thanks Jon - been searching for that manual but could not find it. Amazing that for all of Google's power, there are things it can't dig up! How did you find it?

From page 27 of the pdf file:
SINGLE PHASE OPERATION
THREE HORSEPOWER MOTORS
The motors supplied with single phase, 3 horsepower Unisaws are
designed to be operated from a 220-240 volt power system.
The single phase Unisaws are intended to be used on a circuit that has
an electrical outlet that looks like the one illustrated in Fig. 112. The tool
has a plug similar to the plug illustrated in Fig. 112. Make certain the
tool is connected to an outlet having the same configuration as the plug
(NEMA L-15R). No adapter is available, or should be used with the tool.
CAUTION: IN ALL CASES, MAKE CERTAIN THE RECEPTACLE IN
QUESTION IS PROPERLY GROUNDED. IF YOU ARE NOT SURE,
HAVE A CERTIFIED ELECTRICIAN CHECK THE RECEPTACLE.
The single phase, three horsepower Unisaw motors are single voltage
motors and cannot be connected to operate at a voltage other than
220-240 volts.

Shows picture of plug too.
If I read correctly on wikipedia, 3 phase will have four wires and ground:
EDIT: section below did not copy correctly, see link above for correct version
L1 L2 L3 Neutral Ground /
Protective Earth United States
(common practice1) Black Red Blue White or Gray Green, Green/yellow striped or a bare copper wire United States
(alternative practice2) Brown Orange Yellow Gray or White Green

EDIT 2: Link to pictures of 3 phase plugs. (notice I'm trying to help get rid of the do not buy excuses?)

[Tom Slick]

just to be confusing 3 phase can have 3 or 4 or 5 wires/blades depending on if it is wye or delta wiring, although it's probably 208v 3ph if it is 3ph.
Having 3ph in a residential area is very unlikely.

It could have any of the plugs from this chart where the voltage column has a 3Ø but it could also have a twist lock plug....the best way to tell is to read the data plate on the motor.

[poolhound]

Thanks Jon - been searching for that manual but could not find it. Amazing that for all of Google's power, there are things it can't dig up! How did you find it?

Go to this website for all parts, owners manuals etc for DeWalt, Delta, Porter Cable and Black & Decker.


http://www.dewaltservicenet.com/

[radhak]

Wow, thanks Tom, for that table!

And Jon, that manual and the link is mighty helpful, thanks again.

The plug from the manual looks like this :



Which I guess points to the 4th row, 2nd or 6th column. Need to check what is the amperage of the Unisaw. Again - points to a single phase.

[poolhound]

Maybe it would be a good idea to call the seller and get him to describe the plug. That way you could be closer to figuring out wether it is single or 3 phase. At least if he tells you it has 4 pins you will know it must be 3 phase.

[radhak]

Update : A gloat and NO regrets!!!

I BOUGHT IT!

Tentatively, that is. I have paid him an advance and will get the saw next week!!!

I went there and checked out the machine. The label on the motor says single phase. The Plug is as described in the manual, put into an extension cord (one of the thickest I've ever seen, maybe a half-inch thick). The plug to that cord seems to be a twist plug, similar to the one shown in the chart above (6th row, 6th column).

From everything I see, it's a single phase. The seller tells me the reason he was confused was because he thinks there's a 3 phase connection also in the shop. I am assuming it's possible for the shop to have a single phase and a 3 phase wiring running parallel. Somebody tell me that's possible, please .

The only alternative possibility is that somebody rigged up this unisaw to be a 3 phase, and never changed any of the plug-points, and did not document / mark that fact anywhere; which'd be pretty irresponsible, and also a bit remote.

The saw itself runs great - he's finishing off his last job on it and I saw it in operation. I felt it has a slightly more noise than the powermatic I have worked on a couple of years ago, but most probably has to do with lack of TLC. There's no wobble in the blade, the fence seemed dead-on. It's a Unifence, something I'm not used to. He told me it's a new fence as the older one didn't work well. He has extension tables built all around it - I'm sure he'd just give all that up if asked, but I may not have space for it. I think I'd be happy with just the extension table on the right side that came with the saw (I think).


Anyway, he's shutting down his shop, so he has a ton of stuff to simply give away for as cheap as possible. He threw in a couple of recently-sharpened Freud blades too; and I picked up a PC trim router, a tiny craftsman jointer and a grinder for $15 each. Need to research that jointer : never seen anything that small : just 2 feet long and easy to lift !

He has many more stuff - the other Unisaw, a miter saw, nail guns, larger routers, compressors, et al, but I don't have space in my garage. Affording it would have been a lesser problem - he just wants to almost give it away.

I should thank all of you for persuading me to grab this opportunity. But seeing that I have not yet told LOML, and am still trying to think up a way of sneaking this in, maybe I should wait for your advice on how to deal with that first !

I'm just kidding - Thanks for all your help and input, everybody. Love this forum!

[Stan]

Sweet deal radhak, I'm sure you'll enjoy your new "ol' arn" saw.

[Tom Slick]

It is possible to have single and 3 phase. Sounds like you have a nice 220v single phase table saw.


EDIT: Just to clarify the above sentence should read: It is possible to have single and 3 phase in the same building/area etc.

[shoottx]

I am glad you went ahead with the deal. You have bought a heck of a nice saw for very little. And if you ever want to sell it you will get your money back.

I still am just jealous. This is like buying a BT3K for $20.00

[Uncle Cracker]

UC, so I guess if it is a 3 phase I might as well forget about it?

What I don't understand is, if it comes single phase out-of-the-box, why'd anybody convert it to 3phase?

Yeah, that's pretty much it. You'd have to replace the motor and switchgear to use a single-phase connection, or obtain the aforementioned phase converter or VF drive.

Folks use 3-phase for very large motors (only option), but also sometimes for smaller ones. If there is 3-phase power available, it's a good option. Three phase generally uses less current to do the same work as single phase (because of work split between 3 legs instead of 2, and sometimes higher voltages, so wiring and switchgear are usually lighter and cheaper.

[poolhound]

I happened to be down in Mesa and went into Timber Woodworking. A nice new 3hp Delta was approx $1800.

Once you get it home and installed you are going to have a big grin on your face every time you make a cut!!!

[radhak]

I happened to be down in Mesa and went into Timber Woodworking. A nice new 3hp Delta was approx $1800.

Once you get it home and installed you are going to have a big grin on your face every time you make a cut!!!

Yup - I have that grin already - though surreptitiously, as LOML still doesn't know what's coming in !

This has been a blessing in disguise - I cleaned up the garage a lot this weekend, throwing out a lot of stuff that I was saving to use 'one of these days', or that the kids had outgrown. At the end of it, I think I have a real good workshop going, even without a Unisaw! Once it occupies it's rightful center-stage, this is gonna look so good I might even post pictures !

[radhak]

Yeah, that's pretty much it. You'd have to replace the motor and switchgear to use a single-phase connection, or obtain the aforementioned phase converter or VF drive.

Folks use 3-phase for very large motors (only option), but also sometimes for smaller ones. If there is 3-phase power available, it's a good option. Three phase generally uses less current to do the same work as single phase (because of work split between 3 legs instead of 2, and sometimes higher voltages, so wiring and switchgear are usually lighter and cheaper.

Thanks UC, I didn't read this earlier. I guess you'd have seen by now that we managed to infer that this saw is a single-phase, and hence I have committed to buy it.

I even had the electrician come in and draw up a 240 volt outlet in the garage for me. He stiffed me for $150 just for that small work, but I always needed one of that, and I'm very wary of electrical stuff, so I'll live with it.