wiring/conduit question

[rwe2156]

Maybe you answered, but why do you need 2 - 220V circuits?

If you're running 2 machines, they can go off the same circuit.

[mound]

(the "reply" function to include a quote seems to be crashing the website for me today with a 500 error, but the top-level "reply" is working.)

@srv52761 - thanks for the writeup and Construction Monkey box fill calculator looks very handy!

@rwe2156 - I thought that you could only have one outlet on a 220V circuit for something with a motor attached.. Or maybe that's only for appliances?   
Either way,  I suppose it's true that if I can put two outlets on a single circuit, I could power both the tablesaw and jointer (which would never be run simultaneously in my one-man setup) to simplify things.  I can be guilty of overkill but can be easily talked out of it too

[TDKPE]

I thought that you could only have one outlet on a 220V circuit for something with a motor attached.. Or maybe that's only for appliances?

There's nothing in the NEC that differentiates between 240V general purpose circuits and 120V circuits.  At least not that I've ever seen.  

Either way,  I suppose it's true that if I can put two outlets on a single circuit, I could power both the tablesaw and jointer (which would never be run simultaneously in my one-man setup) to simplify things.  I can be guilty of overkill but can be easily talked out of it too

I have 6 receptacles on my only 240V circuit in my little shop (20A).  My 1 hp lathe with VFD, my 2 hp RAS, and my 3 hp Unisaw all share that circuit, and the 'extra' receptacles are mainly there because I didn't know where anything would be after moving stuff around a lot.  Which I've done, though now I don't expect to move things around again.

You have only two (well, minimum of two) small appliance branch circuits (SABC) in your kitchen, and you plug in all sorts of high current appliances at will, but you don't normally run them all at the same time.  Same thing with the 15A (usually) circuits on non-kitchen rooms, where a space heater and vacuum cleaner together would trip the breaker.  So don't run them at the same time.

[srv52761]

I have  4 receptacles on my 240 volt, 30 amp circuit, and two receptacles on my 50 amp 240.

I  used the emt as my ground and approved face covers.  That eliminated having to have any ground wire at all.  It made quite a difference in making my splices and terminating at the receptacle.  
   Even with that, I used one box with a 1/2" raised cover for my splices with an attached box for the device.

Don't be so quick to dispatch the idea of using the conduit as your ground.  Do some more research.  Mike Holt's forum is well respected among electricians, engineers, and inspectors.  Studies have demonstrated conduit, including EMT,  sized appropriately for the conductors as a ground is superior to copper wire.

[mound]

Thanks.. Good to know it's common practice to chain multiple 240v outlets in series for one-man woodworking shops.  that will simplify things. 

Also thinking along those lines that instead of each 110/20 outlet being its own circuit, maybe I'd run only two, but run them both all the way around through every outlet position into 2-gang boxes.  That way the left and right receptacles at each spot are their own circuits in case two things needed to run together in the same place.

[Roly]

I like to use brown and ivory to distinguish the circuits.   If I run a router and a large shop vac on the same circuit it will trip.   Roly          not sure if they got the new reply working correctly now but just in the last few minutes could I post.  Roly

[mound]

Thanks Roly...  I can use the main "Reply" button to reply to the end of the thread, but trying to reply to an individual response fails.

[lincmercguy]

"Don't be so quick to dispatch the idea of using the conduit as your ground. Do some more research. Mike Holt's forum is well respected among electricians, engineers, and inspectors. Studies have demonstrated conduit, including EMT, sized appropriately for the conductors as a ground is superior to copper wire."

My neighbor, who is a master electrician, said this is no longer allowed, but didn't say if that was an NEC or a state thing. He had me run a ground wire in each conduit, ground each box and each device. I didn't question him since he pulled the permit.

[lincmercguy]

"I like to use brown and ivory to distinguish the circuits."

One trick my neighbor taught me was to group the wires by circuit, then give each group a specific number of tape loops before the whole thing is wrapped for the pull. Are you using ivory as a hot? Not sure that's allowed unless you tag it as a hot on each end.

[srv52761]

<p>

"Don't be so quick to dispatch the idea of using the conduit as your ground. Do some more research. Mike Holt's forum is well respected among electricians, engineers, and inspectors. Studies have demonstrated conduit, including EMT, sized appropriately for the conductors as a ground is superior to copper wire."&nbsp;</p><p>
My neighbor, who is a master electrician, said this is no longer allowed, but didn't say if that was an NEC or a state thing. He had me run a ground wire in each conduit, ground each box and each device. I didn't question him since he pulled the permit.

</p><p><font color="#e82a1f">May be a local restriction.&nbsp; It is still allowed in the latest (2020) edition of the NEC</font></p><p><font color="#e82a1f">https://www.mikeholt.com/newsletters.php?action=display&amp;letterID=2323<br></font></p><p><a href="https://www.mikeholt.com/newsletters.php?action=display&amp;letterID=2323">Link to Mike Holt article.</a><br></p><p><font color="#e82a1f">.</font></p><p><br></p><p>

"I like to use brown and ivory to distinguish the circuits." One trick my neighbor taught me was to group the wires by circuit, then give each group a specific number of tape loops before the whole thing is wrapped for the pull. Are you using ivory as a hot? Not sure that's allowed unless you tag it as a hot on each end.

<br></p><p><font color="#e82a1f">I think the differing colors refer to the actual receptacles, and not the conductors, so you can identify quickly which circuits are in use.</font></p>