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Steve Roxberg
01-25-2008, 11:14 AM
I'm adding some wiring to the shop and have a question.

Today the table saw and jointer share a single 220 outlet and I just swap out the plugs. I'm tired of doing that so I have the following question.

Can you have two 220 outlets on a single breaker?

From what I've seen unlike a 110 outlet which has inbound and outbound contacts for stringing outlets together. I've never seen that on a 220 outlet, so if it's not a code violation how do you do it? I'm assuming I would create a small pig tail to feed the first outlet and wire nut the pig tail, the inbound and the outbound wires together in the box, or in a seperate junction box above the outlet.

Your thoughts are appreciated.

Brian Fulkerson
01-25-2008, 11:40 AM
In California, code requires each 220 outlet to be on its own deticated circuit. Check with your local electrical codes to make sure, but my assumtion is that it is the same in most places.

Joe Chritz
01-25-2008, 11:49 AM
Code may require that it is only 1 per circuit. I am not familiar with the NEC to say for sure. There are people who are that will answer for sure.

Don't wire anything that isn't to code at a minimum, remember the NEC is the minimum standards.

That said, an outlet that has nothing drawing from it just sits there.

Joe

Jason Beam
01-25-2008, 12:12 PM
In California, code requires each 220 outlet to be on its own deticated circuit. Check with your local electrical codes to make sure, but my assumtion is that it is the same in most places.

Not an expert, by any means, but isn't that rule subject to circuit size, too? As I (vaguely) recall, a 20A 240v circuit can have more than one receptical on it, for example, but a 30a one cannot. Hopefully a californian electrical inspector could chime in? :P

Paul Kinneberg
01-25-2008, 12:33 PM
Not sure about CA but I have two 220 outlets on 4 different runs in my shop and the MN inspector signed off on them.

Eric Haycraft
01-25-2008, 12:36 PM
You can check out the NEC online for free (www.nfpa.org). I think that it is section 210 that you are looking for of document 70 which is the NEC.
If I am reading it correctly, there is no requirement that says 1 outlet only with the exception of dryers, ranges, etc. The number of 'taps' depends upon the number of amps the circuit can supply.. For example, a 15 amp circuit can have 14 taps while a 50 amp can only have 12. I highly doubt that california or kansas would deviate from this.
Also, others may interpret the NEC differently, so read it yourself and check with your local inspectors since they have the ultimate say.

Brad Townsend
01-25-2008, 12:39 PM
Don't know if it's code or not, (our county has no electrical inspection) but I installed some of these:
http://www.leviton.com/OA_HTML/ibcGetAttachment.jsp?cItemId=uJOzqJxegTp-RlNqaUj6-Q&label=IBE&appName=IBE&sitex=10026:22372:US
Since I only can run one machine at a time, couldn't see where there would be a problem. They can be ordered through any electrical supply house.
http://www.leviton.com/OA_HTML/ibeCCtpItmDspRte.jsp?item=3386&section=10928

Rob Russell
01-25-2008, 12:47 PM
The NEC rules about Branch Circuits allow multiple receptacles on 15, 20 and even 30 amp circuits. The code section is article 210 - Branch Circuits if you want to read about it.

On 15 amp circuits, receptacles must be no larger than 15 amp rated.
On 20 amp circuits, receptacles can be either 15 or 20 amp rated (assuming there is more than 1 outlet).
On 30 amp circuits, receptacles must be 30 amp rated.


Rob
Addy protocol: unlicensed, homeowner electrician

Steve Roxberg
01-25-2008, 12:49 PM
Wow, thanks guys.

I should have the new Dust Gorilla (stealth gloat) running this weekend.

Rob Russell
01-25-2008, 12:52 PM
You can check out the NEC online for free (www.nfpa.org (http://www.nfpa.org)). I think that it is section 210 that you are looking for of document 70 which is the NEC.


I wasn't aware that the NEC was available online for free. The NFPA is still selling it. Where on their site did you find it available online for free?



If I am reading it correctly, there is no requirement that says 1 outlet only with the exception of dryers, ranges, etc. The number of 'taps' depends upon the number of amps the circuit can supply.. For example, a 15 amp circuit can have 14 taps while a 50 amp can only have 12. I highly doubt that california or kansas would deviate from this.

The tap rule is typically a commercial requirement, not a residential one.



Also ... check with your local inspectors since they have the ultimate say.

Totally agree!

Rob

Eric Haycraft
01-25-2008, 1:00 PM
I wasn't aware that the NEC was available online for free. The NFPA is still selling it. Where on their site did you find it available online for free?

Go here:
http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70
Near the bottom are links to view the documents for various years. You can't download or store them, but for the casual user it beats paying 70 bucks.

Joe Chritz
01-25-2008, 1:08 PM
Rob is generally the man with the plan when it comes to the NEC info. Unfortunately before he posted I couldn't recall who it was that answered my question a while ago about a subpanel box.

CA deviating from the national code wouldn't surprise me at all. There are lots of rules in place in some areas that are much more strict than other areas. Building codes is one example. Some are for good reasons, earthquakes others for other reasons.

I have several outlets on a 20 amp / 220 for the same reasons. One machine at a time.

Joe

Rick Christopherson
01-25-2008, 1:09 PM
There is nothing in the NEC to preclude multiple outlets on a 240 volt circuit. I also highly doubt that California is any different. The reason why this information gets stated is because someone asked a local inspector a question, and the inspector automatically assumes they are asking the common question about appliance outlets, so he gives a default answer. Your dryer and range must be on dedicated circuits, and this is specifically stated in code. Other outlets are not covered by this.

Jeffrey Makiel
01-25-2008, 1:30 PM
Isn't there an NEC rule that states that a motor over a certain hp must have it's own circuit whether it is 110V or 220V?
-Jeff :)

Eric Haycraft
01-25-2008, 1:35 PM
Off the top of my head, i would say yes, but that would only apply to hard wired equipment and not receptacles.

Sam Layton
01-25-2008, 1:59 PM
Hi steve,

I have just finished building my shop, and I did all of the wiring. I have about 4 or 5, 220 outlets on each circut. On 3 of the 4 walls in my shop, I have 220 outlets every 4 feet. each wall is on a different circut. I live in Calif and had all necessary permits. The inspector did inspect my wiring and commented on my 220 outlets. His comment was, that I did my 220 like most people do 110. He said that was fine and singed my permit. In addition all of my outlets are pig tailed. My inspector does not let anything pass unless it is within code.

Hope this helps, Sam

Jason Beam
01-25-2008, 2:32 PM
Hi steve,

I have just finished building my shop, and I did all of the wiring. I have about 4 or 5, 220 outlets on each circut. On 3 of the 4 walls in my shop, I have 220 outlets every 4 feet. each wall is on a different circut. I live in Calif and had all necessary permits. The inspector did inspect my wiring and commented on my 220 outlets. His comment was, that I did my 220 like most people do 110. He said that was fine and singed my permit. In addition all of my outlets are pig tailed. My inspector does not let anything pass unless it is within code.

Hope this helps, Sam

Hey Sam, not to hijack this thread, but how long ago was this and how much did those permits cost you? I'm going to be rewiring my shop this spring and am very curious about this :)

Rob Russell
01-25-2008, 2:38 PM
Off the top of my head, i would say yes, but that would only apply to hard wired equipment and not receptacles.

Eric,

The correct answer is 'No'. :)

There is an entire section of the NEC dedicated to motors. It is entirely permissable to have multiple, large, loads hardwired to a single circuit. There are definitely rules about conductor size, short circuit protection and overload protection that get rather complicated for these kinds of installations. Suffice it to say that we don't want to get into that sort of detail here because it would absolutely confuse things very quickly.

Rob
Addy protocol: unlicensed, homeowner electrician

Rob Russell
01-25-2008, 2:44 PM
Go here:
http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70
Near the bottom are links to view the documents for various years. You can't download or store them, but for the casual user it beats paying 70 bucks.

That's a great resource - I didn't know it was available. I've definitely added it to my Favorites so I can find it again.

Flipping though it, I wouldn't want to look up a whole lot of stuff, but it's great as a reference to point people to when there's a question about what the NEC says.

Al Willits
01-25-2008, 2:55 PM
Insert the required "check with your local codes" here.
fwiw I have a extension cord that has 4 220 outlets on it, it powers my joiner/planer/dust filter and would prob work on the welder I have too.
But not all at the same time.

I does do the DC and joiner or planer just fine and is rated for more amps than they draw together.

Not saying you should do it, but its worked well for me.
I would probably wire them differently if I was in a more permanat shop, but the wife's car has to fit in the shop/garage from time to time also..:)

Al

Rick Christopherson
01-25-2008, 3:07 PM
....In addition all of my outlets are pig tailed. My inspector does not let anything pass unless it is within code.I wanted to comment on this previously, but didn't want to get too long winded at the time. There was provisions in code that permitted using the device as a connection point under certain circumstances. I don't know if these provisions are still in place in the newer code, but it is never a good idea. When in doubt, pigtailing is the best solution. You really do not want the power of the entire downstream circuit feeding through the connectors on a single outlet. This is true regardless whether it is 120 or 240 volt.

Jason Beam
01-25-2008, 3:35 PM
I wanted to comment on this previously, but didn't want to get too long winded at the time. There was provisions in code that permitted using the device as a connection point under certain circumstances. I don't know if these provisions are still in place in the newer code, but it is never a good idea. When in doubt, pigtailing is the best solution. You really do not want the power of the entire downstream circuit feeding through the connectors on a single outlet. This is true regardless whether it is 120 or 240 volt.

Thanks Rick. This is very boldly noted for me. My (recently purchased, first) house is loaded with "piggybacked" outlets - One day, when my tuit becomes circular, the house will be getting rewired and now will be pigtailed as much as possible.

I wanna say thanks to all of you guys who put forth all this information. I know how hard it is to offer advice in sometimes blind situations and I truly appreciate the efforts made by folks like you, rob and tom. :)

Rob Russell
01-25-2008, 3:37 PM
Insert the required "check with your local codes" here.
fwiw I have a extension cord that has 4 220 outlets on it, it powers my joiner/planer/dust filter and would prob work on the welder I have too.
But not all at the same time.

I does do the DC and joiner or planer just fine and is rated for more amps than they draw together.

Not saying you should do it, but its worked well for me.
I would probably wire them differently if I was in a more permanat shop, but the wife's car has to fit in the shop/garage from time to time also..:)

Al

Al,

If you think about it - local electrical codes can't apply to what you're doing because you're not installing anything permanently.

As long as you're running an "extension cord" in a residential environment (I'd assume OSHA could get involved with commercial/industrial environments), the load is a "cord and plug" connected load. It's no different than a table lamp, except it draws more current and possibly runs at a higher voltage.

If you hard-wired the cord in, that would be different.

That's my story and I'm sticking to it. :D

Rob

Eric Gustafson
01-25-2008, 3:45 PM
When in doubt, pigtailing is the best solution.

Being a complete novice, and unaware what pigtailing is, could you clarify? I'm guessing it is paralleling from one outlet to another, but I do not know.

Rob Russell
01-25-2008, 4:04 PM
Being a complete novice, and unaware what pigtailing is, could you clarify? I'm guessing it is paralleling from one outlet to another, but I do not know.

Pigtailing is when you put short (6") pieces of conductor on the device (typically a receptacle, sometimes a switch) and connect those "pigtails" to the conductors in the box with wire nuts or some other form of approved connection. The hot conductor coming in to the box is wirenutted to the hot pigtail for the device and also to the hot conductor that's heading out to the next box. Ditto for the neutral and equipment grounding conductors.

Imagine that you're running a circuit to feed a series of receptacles. The NM-B (aka Romex) feeds into a box. It supplies power to that receptacle and then a run of NM-B heads out to the next box. There are 2 ways to attach the receptacle to the circuit.

The first - pigtailing - means that the device is wired "off to the side" of the circuit.

The other method means that the feeding conductors come into the receptacle and are attached to 1 set of the screws on the side of the receptacle. The conductors that are heading out to feed the next box are attached to the other set of screws on the receptacle. This method may seem easier than pigtailing, but it means that the receptacle is much more inserted into the circuit and can cause more of a voltage drop down-circuit.

There are cases where it's a requirement to "pigtail" devices because it guarantees continuity of the neutral conductors.

If I've just made this confusing, holler and I'll try to find a good picture somewhere.

Rob

Al Willits
01-25-2008, 4:06 PM
Thanks Rob, I was just throwing the required CYA in...:)

Al

Steve Roxberg
01-25-2008, 5:02 PM
Ok, great information and now two more stupid questions. This is my first time running conduit (metal EMT)

1. What is the correct way to cut the conduit? I am planning on using a hacksaw.

2. What is the tool called that will remove the burr left by cutting either with a hacksaw, or the correct tool?

Any other conduit warnings or requirements. I will be going in 3/4 conduit directly from the sub-panel to an outlet box.

For a 220 circuit I'll run a red,black, and white wire. Should I also run a green wire and just connect it to the box?

Brian Fulkerson
01-25-2008, 5:57 PM
I stand corrected!! This is refreshing because I can now add a few more 220's of my existing circuits. Thanks Guys!!

David Parker
01-25-2008, 6:01 PM
Steve, I was wondering about a similar question. I know that if you are putting in dedicated 240 volt receptacles, then you would only need to run the red and the black (or two black) wires to carry the 240 volts, plus the green grounding wire if you choose not to use the metal conduit as your grounding connection.

I would like to have 120 volt receptacles mounted adjacent to my 240 volt ones to provide greater flexibility (plug in my 240 volt lathe and a 120 volt light on the lathe for instance).

I was considering on running a white neutral wire from the sub-panel in addition to the two black and green ones. This would allow me to wire up a 120 volt receptacle adjacent to the 240 volt one. Is it acceptable practice to use one of the black wires from a 240 volt run in conjunction with a neutral to get your 120 volts? (This presumes that I'll use an adequate gauge wire, likely 10, and will use 20 amp outlets for both the 240 and 120 volt receptacles with a 20 amp breaker.) Or should I run a separate line for the 120 volt and use a separate circuit. Also, can the 240 volt and 120 volt receptacles be contained within the same box or do they require separate boxes? Thanks.

Eric Gustafson
01-25-2008, 6:45 PM
If I've just made this confusing, holler and I'll try to find a good picture somewhere.

Rob

No need. That is perfectly clear and I can see why that is better. Does the code require pigtailing? The reason I ask, is that I doubt any outlet in the house was done so, except for a few I have replaced and did it just to make it easier to insert the outlet back in the box.

Chris Padilla
01-25-2008, 7:40 PM
The first - pigtailing - means that the device is wired "off to the side" of the circuit.

:( Shoot...I didn't pigtail my 120V/20A circuits and I agree that it is a good idea now that I think about it. Looks some minor rewiring is in my future in the garage....

However, all my 240V/30A circuits are dedicated circuits--i.e. one outlet per circuit. :)

Chris Padilla
01-25-2008, 7:41 PM
Hey Sam, not to hijack this thread, but how long ago was this and how much did those permits cost you? I'm going to be rewiring my shop this spring and am very curious about this :)

:rolleyes: Permits? :rolleyes: What are those? :confused:

;) :D

Michael Lutz
01-25-2008, 8:01 PM
Dave,

I would run a seperate 120V circuit for the outlet instead of just running a neutral. I do realize that if you shut off the 240V breaker you would still have power to the box, but I would prefer this to unbalancing my loads. I don't really know what the NEC says about it, but it would be similar to a dryer outlet which has a neutral connector to power the 120V equipment except that it would be a seperate plug.

Mike

Rob Russell
01-25-2008, 8:55 PM
Ok, great information and now two more stupid questions. This is my first time running conduit (metal EMT)


Stupid is NOT asking questions. You're way ahead of the game.


1. What is the correct way to cut the conduit? I am planning on using a hacksaw.

2. What is the tool called that will remove the burr left by cutting either with a hacksaw, or the correct tool?

Any other conduit warnings or requirements. I will be going in 3/4 conduit directly from the sub-panel to an outlet box.


A hacksaw is fine - that's how I did my first conduit runs. Just make sure that your cut is nice and square.

Emery paper is fine for removing the burrs. You don't need a special tool.

Make sure that the conduit is sized appropriately for the conductors that you're pulling. Make sure that you use the appropriate connectors to terminate the conduit to the panelboards.

What size circuit are you running and what are you using for conductors?


For a 220 circuit I'll run a red,black, and white wire. Should I also run a green wire and just connect it to the box?

Nope - run red, black and green. White denotes neutral and a straight 220v circuit doesn't have a neutral.

Best,

Rob
Addy protocol: unlicensed homeowner electrician

Rob Russell
01-25-2008, 9:22 PM
Steve, I was wondering about a similar question. I know that if you are putting in dedicated 240 volt receptacles, then you would only need to run the red and the black (or two black) wires to carry the 240 volts, plus the green grounding wire if you choose not to use the metal conduit as your grounding connection.

I would like to have 120 volt receptacles mounted adjacent to my 240 volt ones to provide greater flexibility (plug in my 240 volt lathe and a 120 volt light on the lathe for instance).

I was considering on running a white neutral wire from the sub-panel in addition to the two black and green ones. This would allow me to wire up a 120 volt receptacle adjacent to the 240 volt one. Is it acceptable practice to use one of the black wires from a 240 volt run in conjunction with a neutral to get your 120 volts? (This presumes that I'll use an adequate gauge wire, likely 10, and will use 20 amp outlets for both the 240 and 120 volt receptacles with a 20 amp breaker.) Or should I run a separate line for the 120 volt and use a separate circuit. Also, can the 240 volt and 120 volt receptacles be contained within the same box or do they require separate boxes? Thanks.

David,

You can run a 120v and 240v circuit off of the same breaker. If you think you'd have any chance of running them at the same time with loads that would approach the circuit limits, I'd run (2) separate circuits.

You can put a pair of (1) 120v and (1) 240v duplex receptacles in the same box.

Rob
Addy protocol: unlicensed Homeowner electrician

Rob Russell
01-25-2008, 9:43 PM
Does the code require pigtailing? The reason I ask, is that I doubt any outlet in the house was done so, except for a few I have replaced and did it just to make it easier to insert the outlet back in the box.

That's a loaded question. When was your house built? What code had been adopted in your area at the time the house was built? Is the local code based on the NEC? Are there local modifications to the NEC?

Not pigtailing can make it easier, especially in the older, smaller boxes that got used. Let's not get into box fill requirements here.

If you have the time and energy, pigtailed all your receptacles is a nice idea. While you're at it, write the circuit breaker number on the backside of the receptacle & switch plates.

Rob
Addy protocol: unlicensed homeowner electrician

http://www.sawmillcreek.org/images/misc/progress.gif

Eric Gustafson
01-26-2008, 1:07 AM
My home was built in the late 60's, and it was in the county here where there wasn't much in the way of inspections, permits and the like. The question is more pertaining to code today and trying to get the house up the latest and greatest when I have the chance. Pigtailing is something I will consider and surely will do in the shop.

But, I hear you on the box fill limits. I will keep those in mind. Thanks.

Tom Veatch
01-26-2008, 1:22 AM
...I was considering on running a white neutral wire from the sub-panel in addition to the two black and green ones. This would allow me to wire up a 120 volt receptacle adjacent to the 240 volt one. Is it acceptable practice to use one of the black wires from a 240 volt run in conjunction with a neutral to get your 120 volts? (This presumes that I'll use an adequate gauge wire, likely 10, and will use 20 amp outlets for both the 240 and 120 volt receptacles with a 20 amp breaker.) Or should I run a separate line for the 120 volt and use a separate circuit. Also, can the 240 volt and 120 volt receptacles be contained within the same box or do they require separate boxes? Thanks.

You can certainly use one of the black/red legs of the 240 circuit in conjunction with the white neutral for 120v. Three conductor (+ ground) NMC is available for just that application. 12ga wire is perfectly acceptable for a 20 amp circuit unless there are abnormally long wire runs involved. There's no need to suffer through installing 10ga wire unless you are seriously considering uprating the circuit to 30a at some future time.

It isn't necessary to separate the different voltage receptacles in different boxes unless some quirk in your local jurisdiction's code requires it. You can get dual voltage duplex receptacles (http://www.levitonproducts.com/catalog/model_5842.htm?sid=0A66EFC4979266953265159BA1C112B F&pid=1208)in which one of the outlets is 120 and the other is 240. Be difficult to split that one between two different boxes.

Sam Layton
01-26-2008, 1:42 AM
Hi Jason,

I had my final inspection on my shop in July 07. I obtained permits for my house and shop. I almost tore my house down and rebuilt it, and built my new shop. I can't remember how much my permits were, but I will find out and let you know. I do remember when I obtained my permits, I had two options for my electrical permit. one was to pay so much for each outlet, panel etc. Two, was to pay a flat fee for the entire house and shop. I opted for the flat fee. I rewired my entire house as well as my shop. I am in Glendora, Calif.

Sam

Rick Christopherson
01-26-2008, 1:45 AM
There's no need to suffer through installing 10ga wire unless you are seriously considering uprating the circuit to 30a at some future time.Because he is not permitted to install 15 or 20 amp outlets on a 30 amp circuit, using #10 wire for a multiwire branch circuit would be pointless unless he plans to abandon the standard outlets if/and when he were to make this upgrade.

Sorry. I know that you and I are in agreement on this, but the previous poster may not have known this when he suggested that he might use #10 wire.

Dave MacArthur
01-26-2008, 2:36 AM
Ahh, the "10 ga. future expansion on a 20 A circuit" issue! Always a crowd pleaser, sure to bring out discussion on CB protecting the circuit not the equipment, everyone agreeing that a 20A CB on a 20A circuit you just happened to uber-wire with 8 ga or 10 ga would be fine... then someone crosses the CB and the receptacles, someone shoots their eye out with a BB gun, and it all goes downhill ;)

Here's a link in my sig which is extremely useful as a basic garage shop/NEC initial reference. When in doubt, I personally pull up the SEARCH page here, and put "Rick Christopherson" in as the required author, then type a few key words such as "220 receptacle". I have never read a thread on shop power questions where I disagreed with Rick.

I love these threads though, like watching "Most Crazy Car Chases"--you know a big crash is coming, but you just can't stop watching! Having asked all the same questions in this thread myself, I find I'm still interested in the answers despite having wire in conduit and permit in folder.
Good luck!

J. Greg Jones
01-26-2008, 7:00 AM
When in doubt, pigtailing is the best solution. You really do not want the power of the entire downstream circuit feeding through the connectors on a single outlet. This is true regardless whether it is 120 or 240 volt.

I have a question on pigtailing a 120 volt circuit. If the 120 volt circuit must be GFCI protected, will a GFCI receptacle still protect all non-GFCI receptacles downstream or must the circuit have all GFCI receptacles or a GFCI breaker?

Rob Russell
01-26-2008, 7:45 AM
I have a question on pigtailing a 120 volt circuit. If the 120 volt circuit must be GFCI protected, will a GFCI receptacle still protect all non-GFCI receptacles downstream or must the circuit have all GFCI receptacles or a GFCI breaker?

Greg,

That's a good question.

You can use the first/GFCI receptacle to protect the entire circuit. To do so means using the marked Line and Load screws on the GFCI receptacle - which isn't pigtailing. You could then pigtail all of the other receptacles on the circuit.

If you really wanted to avoid voltage drop everywhere on the circuit, you could pigtail every receptacle, but that would mean either using a GFCI breaker or all GFCI receptacles.

IMO, for a home workshop, just running #12 and a 20 amp circuit with a 20 amp GFCI receptacle at the front of the circuit really should be fine.

Rob
Addy protocol: unlicensed homeowner electrician

Tim Marks
01-26-2008, 7:48 AM
For a 220 circuit I'll run a red,black, and white wire.
Unless you are wiring something that needs 110 and 220V, so you only need a two conductor (+unshielded ground) cable... three conductor is a PIA to run, especially if you are talking about 10 gauge.

You can use the normal black/white romax. NEC requirements are met by covering the white wire with electrical tape or something else to make it black at both ends (I use shrinkwrap tubing) so a future electrician understands it is a "hot" insteal of neutral wire.

I would strongly recommend that you wire your 120V outlets to a separate breaker. I doubt your county inspector will be happy if you mix 120V and 220V recepticles in the same box.

J. Greg Jones
01-26-2008, 9:06 AM
IMO, for a home workshop, just running #12 and a 20 amp circuit with a 20 amp GFCI receptacle at the front of the circuit really should be fine.


Thanks Rob! I'm still in the planning stage of wiring my shop and what you described is exactly what I had in mind, but I had not given any thought to pigtailing the 120 volt outlets.

Rick Christopherson
01-26-2008, 12:22 PM
Thanks Dave! ;)

Tom Veatch
01-26-2008, 12:33 PM
Ahh, the "10 ga. future expansion on a 20 A circuit" issue! ...!

Have you ever wondered how many of the "run 10 'cause you might uprate later" advocates have actually followed through with changing a branch circuit from 20a to 30a. There have probably been some, but I tend to doubt that it's a very large percentage.

I know I've never seen a requirement for 30a support on any of the branch circuits in my shop. And if one did develop, I'd be seriously considering running a dedicated circuit. Of course I'm not counting the 120v 6.5 HP shop-vac. (6.5 HP, yeah, right!:rolleyes:)

Michael Lutz
01-26-2008, 1:04 PM
I just ran 30A 240V multi-outlet circuits, because my 5HP TS required a 30 A circuit. I wanted to standardize all my 240V plugs so I wouldn't need to have different plugs and outlets. If I had went with a dedicated outlet for the table saw, I would have been upset. My TS has moved from the original outlet to a different one. Now, I am a hobbiest woodworker and only one machine at a time is on.

Mike

Randall Davis
01-26-2008, 1:11 PM
The tap rule is typically a commercial requirement, not a residential one.

The tap rule was not mentioned. tap and tap rule are two very different things.

Dave MacArthur
01-26-2008, 8:10 PM
Erm... In all honesty, after reading all these "220 volt 12ga-20A vs. 10ga-20A circuit threads" --which honestly, I really DO enjoy!--I now actually find myself wishing I had run at least a couple 10ga circuits because I am looking hard at the new Grizzly ultimate 17" (4.8 or 5hp) bandsaw, and need 30A which I of course did not account for. Of course I can hop up into the attic and run another circuit or change the wire pretty quickly, but it does make me laugh. Almost EVERYONE's side in a discussion can be right at one time or another!

Steven DeMars
01-26-2008, 10:13 PM
I think I would do them in parallel coming out of a small junction box. I do not think you will be able to get two of the proper size conductors into each point to series them like you would a 120VAC receptacle. We used to do it this way in the Chem Plants for a welder & a plasma pipe bevler to run off one location.

Wayne Cannon
01-27-2008, 2:42 AM
The inspector didn't complain about my running multiple 20 A 240 V outlets per circuit breaker at either the drawing or the final inspection. There is a restriction on the number of receptacles you can have per circuit for a given breaker capacity and wire size. I don't remember the ration, but if I recall correctly, it's greater than the breaker/wire capacity, but less than twice the breaker/wire capacity.

Dennis Parslow
02-04-2008, 11:20 AM
I just ran 30A 240V multi-outlet circuits, because my 5HP TS required a 30 A circuit. I wanted to standardize all my 240V plugs so I wouldn't need to have different plugs and outlets. If I had went with a dedicated outlet for the table saw, I would have been upset. My TS has moved from the original outlet to a different one. Now, I am a hobbiest woodworker and only one machine at a time is on.

Mike

hey Mike exactly which plugs did you go with? I was about to do the same as you but haven't bought the plugs/receptacles yet. Thanks,

Jim Becker
02-04-2008, 1:55 PM
I think I would do them in parallel coming out of a small junction box.

This is my preference as it's much easier to change or add a location later for shop flexibility. Be sure to mark the outlets so you always know which ones are on a common circuit. It also provides for more space to work on the connections...unless you put in a deep, double box with a mud-ring at each outlet location, there is not a whole lot of room in the outlet box for things like pigtails to daisy-chain to another location...and that really holds true for the 30 amp circuits that use #10 wire.


I wanted to standardize all my 240V plugs so I wouldn't need to have different plugs and outlets.

My preference here, too. All my 240v 20 amp and 30 amp outlets use twist-locks of the appropriate version for the circuit rating. The makes moving something to an alternate location, either temporarily or "permanently" very easy. I chose twist-locks, despite their higher cost, because I'm more comfortable with the positive engagement they provide.

Vernon Taylor
02-04-2008, 7:31 PM
I will not add anything to the specifics here other than that I find it best to buy supplies from a wholesale electrical supply house rather than at the Borgs. Tell them what you are doing and make a sketch of your situation,I have found their advice to be invaluable as they are familiar with local codes and the inspectors
requirements. I have also found that prices are very competive as you are not paying for packaging for retail display,also the counterman will gather your order. I also feel I have avoided unnessesary trips because they make sure I have everything I need.

Michael Lutz
02-05-2008, 1:08 PM
Dennis,

I used Pass and Seymour Nema L6-30P plugs and L6-30R receptacles. These are a standard plug style, so you may have other suppliers in your area. These are twist lock receptacles. The recptacles are mounted in the center of a 4" x 4" box. The plugs are large. They were also about $10 each.

Mike