Mod note: Moved from http://www.doityourself.com/forum/el...ed-garage.html because it was confusing the issue.

pcboss,

Of course I know that.

I am asking another thing.

I am asking how he will convert the incoming #6 conductors that he said that will be four single conductors consisting of 2 Hots, 1 Neutral, 1 Ground for that is clear a double pole breaker is needed... but then for the rest of the wiring at the shed that will be of #12 wires consisting of just 1 Hot conductor, 1 Neutral and 1 Ground, how he will wire that #12 wire to the double pole breaker serving as a disconnect means in the shed? How he will proceed to do it?

I know is possible, I just want to know the method that will be used.

 

For the 20 amp 120 he can use one 20 amp single pole breaker. I'd just use #12 (white, black, green) and just pull new wires if I ever wanted to convert.

However plan "B" would be to pull the future wires now. Use red and black (or tag one black on both ends) for the hots.

• For the 20 amp 120 circuit install a 20a single pole breaker.
• At the breaker use a #12 pigtail to reduce the #6 black to fit the breaker (if needed)
• White and green will not need reduction. Connect as usual.
• Cap off the red (or tagged second black). It is not connected.
• At the shed install a 4x4 box and a single pole 20 amp switch to act as a disconnect.
• Cap the red (or tagged second black).
• Run #12 to receptacles and fixtures.
• Use a GFCI receptacle for the first receptacle and daisy chain the other receptacles off the load side.
• Lights do not need GFCI protection.

Plan "C" Install a 20 amp multiwire 120 volt circuit using all four wires. You would use a double pole 20a 240 breaker or two handle tied single pole 20 amp breakers.This gives you two 20 amp 120 volt circuits without needing a subpanel. You would use an unfused two pole air conditioner disconnect at the shed instead of a single pole switch and a 4x4 box.

 

Maybe with this diagram my specific question will be now understood... Please excuse me, but for some reason it's almost impossible for me to properly express this specific question in English. Sorry for any misunderstanding.

NOTE: The next diagram does not represent an official wiring procedure, it is just for temporary illustrative purposes only!

 

See my reply above yours. He would not use a subpanel at the shed for 120 volts. Only a switch as disconnect. If he wanted more power later then the disconnect switch would be replaced with a breaker panel.

 

Let's try to explain it more simple this time.

My point is: If he will run the oversized #6 conductors in the conduit, then why not to just buy a Small Lug Panel like this one:

GE PowerMark Gold 70-Amp 2-Space 4-Circuit Indoor Single-Phase Main Lug Circuit Breaker Panel-TL270SCUP - The Home Depot

Connect all the #6 conductors accordingly in the small main lug at the shed.

Then, use a 20Amp double or single pole breaker at the small main lug (if double is used, wire just one pole) with the #12-2 Romex, etc. connected to that breaker, neutral and ground accordingly, that will serve as a Main Disconnect at the shed; and finally run the #12-2 Romex, etc. to the desired 20Amp circuit that will supply power to all the devices you listed in the thread.

Come on, we are talking about a difference of just $20 bucks to have all those #6 conductors that will be anyway already running inside the conduit connected to a proper Main Lug Panel in the shed.

Why not to do it that way??? ...


Just $20 Bucks!!!


...Instead of leaving one of those #6 ungrounded conductors that will be already running inside the conduit unused. If we were talking about someone running just the #12 or #10 conductors for a single 20Amp circuit at the shed, it will be logical not to spend more on a Subpanel, etc. but in this case the #6 conductors will be already running in the conduit from the Main Panel to the Shed, so the additional money needed to have a Small Lug panel that will properly receive the #6 conductors is just $20 bucks; in this case is explicit more practical to already have that small lug panel serving as a Main Disconnect in the shed!


Thanks.


Jos

 

Most here would probably not recommend a small main lug panel because it does not have a disconnect nor enough room for future circuits. Most would recommend at least a 12 space 100 amp main breaker panel. The 100 amp main breaker provides the disconnect if more than six breakers, room to expand and add circuits, and cheaper usually then other solutions because they can be bought as kits with some branch circuit breakers included. However that can wait till it is needed if ever.

 

A 20Amp breaker (around $5 bucks) installed on the small main lug will serve as the disconnect for the 20Amp circuit at the shed.

True, BUT I believe that in the case that he will not upgrade to the 50Amps Subpanel within a year or two, saving just $20 bucks by not having the small lug panel at this moment isn't a significant saving after all.

I prefer to spend $20 bucks now and have those #6 conductors properly wired in the shed since the beginning, then and after a year or so, discard the small main lug and replaced it with a bigger subpanel... to lose those $20 bucks after a year isn't that bad after all... than running oversized conductors just to end leaving one conductor unused for a long period of time and just to end complicating the wire's gauge transition from #6 to #12 at the shed.


Thank you.


Jos

 

Transitioning the #6 wire to #12 can be done simply using wire nuts and a small junction box..

But don't cut the #6 wires especially out at the shed because you will need adequate wire length to replace the junction box with a breaker panel (as a subpanel) in the shed once you upgrade beyond 20 amps.

Transitioning from #6 to #12 (#12 pigtails) at the house panel also lets future electricians or homeowners know that the circuit is a 20 amp circuit for the time being, should you sell the house prior to making the upgrade beyond 20 amps..

 

ray2047,


In one of your replies at the original thread you stated:


Now that Plan ''C'' satisfy all my concerns. On all the confusing question I made and fail on the attempts, I was trying to know what specific method will be used in this case. Your plan ''C'' method sounds more practical and logical to be implemented in this case as well as the small main lug panel I previously recommended.

I'm aware that the AC disconnect in this method replaces the need of the small main lug panel, and the double pole breaker o two handle tied single pole resolve the issue that was highly concerning me regarding the two #6 ungrounded conductors.

However, I have to say that still I prefer to use a small main lug panel with a Breaker as the disconnect method, over the unfused AC disconnect, mainly because the Breaker will provide constant overcurrent protection whenever the shed is left alone with the electrical power on.


Thanks.


Jos

 

AllanJ,

I know that is possible, permitted and ''should'' be safe as long as the wire nuts connections are properly tightened and secured...

... but to be honest I don't like the idea to use any wire nut to connect #6 wire with anything. I just don't feel confident enough using a wire nut for that setup, specially when it requires just a slight untwisting of the wire nut to loosen it. I use wire nut connections for wires up to #10 AWG and recently I don't care anymore about wire nuts and now I use Push In Connectors ONLY!!!


Thank you a lot.


Jos

 

I'm coming into this discussion in the middle and I did not read the original thread that generated this spin-off.With that in mind I would do a combination of what Jos and Ray have suggested. I agree with Jos that if one has run a 240 volt feeder with #6 copper conductors it is penny wise and pound foolish to NOT install a subpanel at this time. I agree with Ray that installing anything less than a 12 circuit panel (it might be a six space-twelve circuit) with a main breaker is foolish from the standpoint of future use.

Jos, you might be forgetting that a "back fed" circuit breaker needs another means of securing it to the panel than simply the cover. Once you purchase the circuit breaker and hold down you might have been better off just buying the main breaker panel, especially if it is just a temporary use of the smaller circuit breaker. Remember also that the input lugs on a main lugs only (MLO) panel have a range of wire sizes that can be used and most likely that range does not go down even close to a #12 conductor.

Another thing you may be forgetting is that the NEC allows for up to six throws to remove all electricity to a building. This has been defined as a maximum of six circuit breakers although not necessarily six poles. In other words, you can have six single pole circuit breakers, six double pole circuit breakers or in the case of a three-phase panel six triple pole circuit breakers. Tandem circuit breakers, those containing two independent circuit breakers in the space normally allowed for a single circuit, are counted as individual circuit breakers so even with their use you can only have a maximum of six handles. The rule allows for the maximum number of circuit breakers than may be installed and NOT the number that may be installed initially.

To clarify, a six space-twelve circuit, panel MUST have a main circuit breaker OR a separate disconnecting means regardless of how many active circuits are initially installed.

 

Assuming an unfused 60 amp A/C disconnect you could at a later time just wire a main lug panel of any number of spaces and it would serve as the disconnect.

Feed would need to be protected by a 60 amp breaker (OCPD).
Main lug panel must be rated for the OCPD or greater.

 

Hi Furd,

I appreciate your reply, it contains a lot of valuable information.

However, regarding this:
I did not forget it; I was actually not suggesting the breaker to be back fed. I was suggesting that the breaker become the Main Disconnect to the dedicated 20Amp circuit at the shed but as follows in the next diagram:



Edit Note: Above diagram shows both poles of the double pole breaker with #12 ungrounded conductors, therefore it should reads 12-3 with ground Romex can be used.




And this version shows that only one #12 ungrounded conductor is connected at just one pole of the double pole breaker, therefore a 12-2 with ground Romex as properly shown can be used.

Like now you can notice the breaker is not back fed because the actual lugs on the small lug panel will receive the incoming ungrounded conductors; it is the breaker that will only contain the smaller #12 ungrounded conductor(s) that will serve the 20Amp circuit the same way it will regularly serves it on any subpanel.

Also about this:

I never suggested that the #12 conductor will be used in the small lug panel, I actually suggested precisely the opposite, that the #6 conductors will be used in the small lug panel lugs, and that the #12 conductors will be connected to the breaker like it is shown in the diagram.


That diagram is the same principle I used in my intermediate Disconnect Means between the Main Service and the Subpanel; with the difference that I used a 60Amp double pole breaker for the incoming #4 ungrounded conductors, and from there the #4 ungrounded conductors continued till the subpanel, then they feed the subpanel directly to its lugs. No main breaker at the subpanel, but the intermediate 60Amp breaker functions as a Main Disconnect. In my case I used a subpanel because I'm feeding 60Amps and because I have 14 circuits out of my subpanel. But in the case we were debating the OP was going to temporary supply just one 20Amp circuit but he wanted to run oversized #6 conductors for a future upgrade to a 50Amps subpanel. That's why my idea was to recommend a temporary small lug panel to properly receive the #6 ungrounded conductors directly to the small lug panel lugs.


I hope that the diagram clarifies all I was trying to suggest.


Thanks a lot.


Jos

 

Yes, your suggestion is certainly acceptable from a code standpoint. The only thing that I would personally question is the use of a single circuit breaker housing when upgrading seems likely at some point in the future. At that future point the single CB enclosure will either need to have the proper size (60 ampere) CB installed and then used in conjunction with another CB panel, or else it will simply be discarded. For only slightly more money (and maybe less in some circumstances) a main breaker panel can be installed at the outset.

My thinking is why do it twice? Install the 6/12 MCB panel with a single pole 20 ampere branch CB for the immediate need and then add additional circuits as needed. No need to change the feeder CB, the building disconnect CB or any of the wiring from the house to the sub-panel.

 

Furd,

Exactly! I do 100% agree with you. All that is what I personally do and will do in my electrical installations. Please, do not understand me wrong, I agree with you about to use a Main Circuit Breaker or a bigger main lug panel to have more space already available for any future upgrading plans... but what I was suggesting with the small lug panel it was not for me but for the OP of the Thread because he specified that he doesn't want to install any subpanel at this moment, but he also specified that he will run four single #6 oversized conductors in the conduit because he will later (not specified when) will then upgrade to a 50Amps subpanel; of course that I believe that is better to go with Main Circuit Breaker main lug panel right now too, but because he clearly stated that he doesn't want to go with any subpanel at the moment, then at least I was trying to suggest him to use a small lug panel as shown in the diagram in order to properly receive the oversized conductors into the lugs instead of leaving one conductor abandoned in the conduit to pull it later, and instead of doing #6 to #12 awg transitions at the shed like he was inferring to do. My diagram is a suggestion just to simplify all the wiring, etc. without using a MCB because the OP stated he doesn't want to use any subpanel at the moment but he still wants to run the oversized conductors from the Main Service to the shed.

But for me it's clear that if I run #6, etc. oversized conductors in a conduit to just supply one 20Amp circuit at the moment, I will still use a Main Circuit Breaker or a Main Lug Center doesn't matter if I will just install one 20Amp breaker to it and have more than 10 more spaces available at the moment, but I will install the subpanel because any change(s) that may emerge at any given moment it will just require to add the correspondent new breaker and a new circuit. After all, most MCB and big Main Lug Centers can cost less than $125 (even as cheap as $40 to 70 depending if they include some breakers or not, etc.), so of course I agree with you; but again it was the OP of the Thread who stated that he doesn't want to use any subpanel at the moment in his shed, but still run oversized conductors in the conduit but wiring it for just one 120Volts 20Amp circuit at this time. So I has been trying to respond accordingly to what he stated.


Thanks.


Jos

 

I agree. a[pojgeolrgntw0aisdjcsk[=