220v conversion question

[krw]

It's not 30' of copper. Go *all* the way back, both legs.

[Lew Hodgett]

Time for an eye exam maybe?

Lew

[Scott Lurndal]

stranded, they're about the same. think 10-2 SJ vs. 12-2 SJ.

scott

[krw]

Well, the 25th. 8-)

[Luigi Zanasi]

From the Anti-FAQ, for everyone's edification.

5.1 HOW DO I WIRE MY SHOP?

As my friend Doug, the journeyman cabinetmaker, says: there's only four things you gotta know about being an electrician:

S--- flows downhill, Payday is on Friday, It may be s--- to you but its bread and butter to them, and Every asshole is a potential customer.

Oops! That was about plumbers. Forget it. Anyway, Doug is just jealous of plumbers 'cause they make more money than cabinetmakers, just like Tom.

Actually, all the regulars and most of the newbies on the wreck are electrical experts. That's why any thread on wiring and electricity gets so many responses. Most of us work with electricity all the time. After all computers and power tools are electrical, and so's the TV we watch Norm on. If you want to change the plug on your tablesaw, you still need to know everything about wiring and amps and volts and watts and volt-amps and wire gauges and phases and power factors and impedance and resistance and plug configurations and panel sizes and capacitors and motors and switches and electrical codes.

But that's OK, don't be afraid. You can trust any wiring and electrical advice from anybody on the wreck, apply it and be absolutely sure that it will meet code and be perfectly safe. No point in getting ripped off by electricians or consulting an inspector. Just ask away on the group and you can be sure of getting a whole lot of accurate and consistent responses, just like when you ask any math question of all the rocket scientists on the wreck.

Luigi

[clare]

At any ont point in time, he is correct. It just switches direction

120 times per second (60 each way)

[clare]

Yes, generally it drops to roughly quarter.. Windings go from parallel to series. 2 windings of 2 ohms each in parallel is 1 ohm, in seies it is 4

[clare]

My old Beaver table saw wouldstart like a bomb when plugged directly into the wall, or on a short 14 ga cord. It often popped a fuse on startup.

Putting it on a 25 foot 16ga cord it never popped a fuse, and took about 3 times as long to come up to speed (this was a repulsion start induntion motor - you could hear when the brushes came out)

[DLB]

I agree, small. But noticable to me.

[DLB]

Not additive? Now I am back to the beginning of understanding. Isn't the motor running at 15amps on either 120v or 240v?

[Puckdropper]

[e-mail] (Doug Miller) wrote in news:h7mvgg$do6$ [e-mail]:

*snip*

So, for truly instantious table saw start up, we should hook the motor up to the 4KV, bypassing the transformer. We'd only need a few microamps at most to power it, therefore all the power we'd need go directly to the saw.

Better add a cast iron body to the cast iron top, though... The slightest imbalance might flip the saw over!

Jokingly,

Puckdropper

[Doug Miller]

No. It runs at 15A @ 120V, or 7.5A @ 240V.

The amperages on the two legs of the 240V circuit don't add, because the two legs are in series with each other. Current is the same at all points in a series circuit.

[J. Clarke]

No. If it draws 15 amps on 120 it should draw 7.5 amps on 240. On 120 15 amps come in the hot and go out the neutral, on 240 7.5 amps go in the hot and go out the other hot.

[DLB]

That is what I did. HD had about 4 9ft 12gauge ext cords. Now they have 2.

[Jack Stein]

Doug, again thanks for taking the time to explain all this for me. Very helpful and informative.

Jack

Doug Miller wrote:

[keithw86]

Just to be clear, I've seen #12 extension cords but no #10.

[Jack Stein]

I bought a 12 gage extension cord at HD and that was hard to find. Well, they had like 50 14 gage and just ONE #12. Harder for the next guy to find:-) Also, the extension cord was cheaper than buying the wire, let alone the wire and plugs. I needed a new cable for my table saw. Pretty awesome that a better quality extension cord with molded plugs is cheaper than buying just the wire.

[Larry W]

Well, if we also bring relativity and quantum mechanics into this discussion, it would be fair to say that at any given time the current might be flowing in any direction you'd care to choose, and what's more, we have no way of telling so!

[Chris Friesen]

Just be aware that it may not be the same cable. Often the spooled stuff is good to 90 degrees C, while the extension cords are only good to 60C.

For most stuff it shouldn't be a problem.

Chris

[Robatoy]

Just like it is possible for a 10ga wire to be more flexible than a

14ga wire. Depends on alloys, strand count, and insulation materials.