a little power apparently goes a long way

[toolguy1000]

...... I did make sure to balance the loads on both legs.

i think that doing that in my panel contributed greatly to more effective power distribution and resulted in better tool performance.

[chopnhack]

Man, I could of used that magic smoke when my cms died, I didn't know they still bottle it

As for the OP, do what works, if in doubt or in your case where there are signs of stress on your grid have a pro come and evaluate it. IIRC the NEC states that loads that are to be left on continuously are to be rated at 1.25x their normal load, so lights, a.c. or d.c. or ambient air cleaner would fall into this category.

[woodturner]

Originally Posted by woodturner:
Lights dimming is a symptom of voltage drop. Voltage drop in a wire increases when more current is drawn, such as when starting a motor. Larger wire has less voltage drop - which is why a "rule of thumb" is to use one wire size larger than required by NEC.

in my municipality, they won't allow that. or at least they wouldn't allow it when i had the garage service done..

Are you saying you municipality will not allow you to install larger wire? That doesn't seem possible, and it is arguably required by NEC for motor applications.

[pelligrini]

some great comments here. interesting that others have shop service similar to mine and work without incident also.

I've never noticed the lights dimming with my subpanel. I did make sure to balance the loads on both legs. The AC and DC are on one and the tools and lights are on the other. In the couple spots I have two duplex outlets, they are on seterate legs.

I used to have a terrible time with power when I was running the shed off of two extension cords. One came from the porch circuit and eventually another from a nearby bedroom window. Never could really run that AC unit due to the voltage drop from the long cords.

sounds like a good test. when can you get my complimentary workpiece to me?

At $58 a BF I might be able to send you an inch of it.

[Cochese]

some great comments here. interesting that others have shop service similar to mine and work without incident also.

They wouldn't allow you to build above code? That doesn't make sense.

[toolguy1000]

If that magic smoke comes out, be sure to replace it.

This Lucas Wiring smoke would seem to be a direct replacement.

now that looks to be one really useful item for the inattantive woodworker.

[toolguy1000]

Lights dimming is a symptom of voltage drop. Voltage drop in a wire increases when more current is drawn, such as when starting a motor. Larger wire has less voltage drop - which is why a "rule of thumb" is to use one wire size larger than required by NEC.

in my municipality, they won't allow that. or at least they wouldn't allow it when i had the garage service done..

Regarding breakers, you can find the trip curves online for your breakers if you are interested. The key point is that a stalled saw will usually take a few minutes to trip a breaker - it won't trip instantly. Stick a fork in a wall socket and it will trip within millisends (please don't try this at home ), but lower levels of overcurrent require much longer to trip the breaker. That's why the 20A breaker in a typical table saw circuit doesn't trip when the motor draws 60A on startup - the duration of the overcurrent is too short to trip the breaker.

but it still wouldn't take 5 minutes to trip the breaker or have the saw motor emit it's, what was that, "magic smoke". one would have to be fairly inattentive to permit that to happen.

some great comments here. interesting that others have shop service similar to mine and work without incident also.

[toolguy1000]

How about some 8/4 Cocobolo?
http://www.woodworkerssource.com/uni...que_items.html

sounds like a good test. when can you get my complimentary workpiece to me?

[Cochese]

If I stalled my saw, I wouldn't wait for the breaker to trip. I'd probably hit the stop switch in a few miliseconds.
Unless if it were a body part jaming the saw. Then I'd probably have bigger things to worry about than a tripped breaker...

I would think that the magic smoke would be let loose from the motor before the breaker for the saw tripped.

If that magic smoke comes out, be sure to replace it.

This Lucas Wiring smoke would seem to be a direct replacement.

[pelligrini]

The key point is that a stalled saw will usually take a few minutes to trip a breaker - it won't trip instantly. Stick a fork in a wall socket and it will trip within millisends (please don't try this at home )

If I stalled my saw, I wouldn't wait for the breaker to trip. I'd probably hit the stop switch in a few miliseconds.
Unless if it were a body part jaming the saw. Then I'd probably have bigger things to worry about than a tripped breaker...

I would think that the magic smoke would be let loose from the motor before the breaker for the saw tripped.

[LCHIEN]

a 30A 220V service can provide the equivalent power of 4 110V 15 A circuits. So a 1.5HP table saw, a 1.5HP DC and another 1.5HP DC and a ~1 HP vac will easily run.

Just keep in mind that the DCs and ship vac tend to run at full power and current when turned on and all ports open (not blocked). Whereas Power tools like saws tend to run at idling current when spinning but not cutting anything, Idling current may be 5 or 6 amps for a 1.5 HP table saw. I always find it impossible to look at meters and do maximum cutting loads to see what is drawn... too dangerous to be looking elsewhere. So I'd recommend you don't try it either.

[woodturner]

what i'm still casually exploring is why the lights seem to dim less now than before.

Lights dimming is a symptom of voltage drop. Voltage drop in a wire increases when more current is drawn, such as when starting a motor. Larger wire has less voltage drop - which is why a "rule of thumb" is to use one wire size larger than required by NEC.

Regarding breakers, you can find the trip curves online for your breakers if you are interested. The key point is that a stalled saw will usually take a few minutes to trip a breaker - it won't trip instantly. Stick a fork in a wall socket and it will trip within millisends (please don't try this at home ), but lower levels of overcurrent require much longer to trip the breaker. That's why the 20A breaker in a typical table saw circuit doesn't trip when the motor draws 60A on startup - the duration of the overcurrent is too short to trip the breaker.

[pelligrini]

it may have something to do with rearranging which leg each circuit is on now vs. where they were before the modification.

I'm guessing that the load is now more balanced.

I only have a 30A@220 breaker in the main panel feeding the subpanel in my shop/shed. All my tools are 110. I've never had a problem with the 60A@110 that's available, even with my large 110 window AC unit pulling 14.9 amps on high, also with four 48" twin tube light fixtures, battery chargers, and a stereo, a Jet 650 DC, and running a tool, be it a DW735 Planer, the 21829 clone, my 6" jointer, or DW618 router. I ran 6/3 from the main to the subpanel. It was drsigned for more than 30A@220, but I haven't needed to up the main breaker yet.

[pelligrini]

Any suggestions as to what type of dimensional material would make for an interesting test?

How about some 8/4 Cocobolo?
http://www.woodworkerssource.com/uni...que_items.html

[toolguy1000]

of voltage drop. With all your equipment running at the same time, lights counted into the equation as well, your 10/3 wire is heating up, along with the breaker and buss bars. No way would I use a 30 amp panel...

fortunately, it hasn't presented a problem. i've never had the 30A 220v feeder breaker in the main panel trip. and even in the rearranged 30A 220v sub panel, the DC, shop vac and activated power tool (only one saw dust generating tool is activated at a time) are all on separate circuits.