$1600 Powermatic 1660804K 66 Cabinet Table Saw 5HP, 3Ph

[davidtu]

Its 3 phase, not sure if anyone can use it (any point in listed 3ph stuff??) but usually $2200--2400

http://www.amazon.com/exec/obidos/tg...X0DER&v=glance

[JBD]

I was going to post that couple days ago but figured nobody would be interested.
Maybe I was wrong?
I started watching all the other PM cabinet saws; but they havnt budged in price.

The Jet JTAS LT 3HP did drop 200 today, but not anything to post about tho.

[geeoh]

Amazon has some excellent bargins on 3 phase power tools (not me no 3ph.)
If anybody is looking for a very nice size planer at over half off:
JET 708584 JWP-208-3 20-Inch 2 Horsepower Planer, 115-Volt 3 Phase
List $1,817.00, now at $870.06 + 149.00 shipping

http://www.amazon.com/708584-JWP-208...609092&sr=1-20

[ryan.s]

Excuse my ignorance but what exactly does 3 phase mean? What are the characteristics relative to a 1 phase motor? Thanks.

[LCHIEN]

Excuse my ignorance but what exactly does 3 phase mean? What are the characteristics relative to a 1 phase motor? Thanks.

Three phase power requires 3-power carrying wires as opposed to two for 1 phase.

The three lines are 120° in phase from each other. THis is almost always used for industrial power applications, very large motors etc.

Among other things the three phases rotate in order so that a starting capacitor that's used in 1 phase motors, is not needed.

[ryan.s]

Three phase power requires 3-power carrying wires as opposed to two for 1 phase.

The three lines are 120° in phase from each other. THis is almost always used for industrial power applications, very large motors etc.

Among other things the three phases rotate in order so that a starting capacitor that's used in 1 phase motors, is not needed.

So from a pratical standpoint what is the difference in the performance of the motor or the operation of the tool? Thanks.

[LCHIEN]

So from a pratical standpoint what is the difference in the performance of the motor or the operation of the tool? Thanks.

I quote Wikipedia:
A three phase induction motor has a simple design, inherently high starting torque, and high efficiency. Such motors are applied in industry for pumps, fans, blowers, compressors, conveyor drives, and many other kinds of motor-driven equipment. A three-phase motor will be more compact and less costly than a single-phase motor of the same voltage class and rating; and single-phase AC motors above 10 HP (7.5 kW) are uncommon. Three phase motors will also vibrate less and hence last longer than single phase motor of the same power used under the same conditions.

But three phase power is not found in homes except very, very rarely. And
3-phase motors are scarce under around 3-5 HP. 3-phase motors because of their simplicity are more reliable than single phase.

[davidtu]

So why isn't it available in home? Or, why are there two different 240v systems when one is clearly better?

[LCHIEN]

So why isn't it available in home? Or, why are there two different 240v systems when one is clearly better?

installation costs and complexity are significantly higher with 3-phase.
I think the motor advantages probably don't start outweighing the labor and infrastructure costs until you get to bigger e.g. 5-10 HP motors. For most other electrical uses, there's not too much, if any, advantages.

In factories and other heavy electrical usage they have 440, 660, and 880V distribution in three-phase. There's also a lot of schemes such as Wye and delta connections and some 208V schemes that allow other wiring options. That' would be too much for home use to allow all those options that bigger motors come in, 110 is standard for home and office construction - all your appliances and small machinery come in one standard.

[lrr]

Three phase converters are available to convert single phase power to 3-phase. For small motors, it wouldn't really make sense, but for high HP motors, ths could be the ticket.