Hello, I would like to start with I know nothing about wiring houses or buildings. With that said I am hoping that I can find some people on here that would be willing to help create a step by step guide for others and myself as I attempt to wire a second or sub panel (not even sure if these are the correct terms). I have a warehouse. on 1 side of it there is a circuit breaker box or service panel with a few circuit breakers... then about 150ft over.... there is another service box that is empty, looks like the wiring was just ripped and torn right outa there?? not sure but no circuit breakers or wiring is in this box...

The GOAL:
Wire that first box to the other service panel(add sub panel or 2nd service panel).
We need to know what materials are needed and tools
Also, step by step as we go along of what needs to be done

Any information you need to help out please ask... I will try to answer to the best of my knowledge but again I know nothing about this.... I am on my way down there now to take pictures... I hope they help!!! Thanks in advance to anyone that helps!


SO LETS START WITH... WHAT IS STEP 1????? Figure out amp usage, measure, how many outlets..??? Let me Know

 

Welcome to the forums!

Step 1A is to read Wiring Simplified. Wiring Simplified is a valuable but inexpensive guide to understanding electrical systems, both the how-to and the why.

Step 1B is to tell us, or show us, what you have now. You say which raises the possibility of 3-phase power, either 120Y/208V, or 277Y/480V, or both. If you can do so safely, kill the power to the working panel, open the cover, and see how many wires, of what color, are feeding the power into it.

A picture would help us see what you have. See How To Include Pictures. A picture of the interior of the second, gutted panel would help, as would pictures that show both panel information labels.

 

It's not just a possibility, it's an almost certainty. The question is which one.. And don't forget 120Δ240 is possible also, especially if the system is older.

 

You mention that this is a warehouse. Most commercial work will require a licensed electrician to be used.

 

For what it's worth, I was at the orange big box mega-mart homecenter today and saw Wiring Simplified (in the electrical aisle) priced at $6.97.

 

That's certainly one more possibility.

 

Wow I didnt expect so many responses so quickly. Thanks! here are some pics of whats going on right now. Hopefully they help.

 

The first pic shown is a single phase panel. The panel you are trying to wire is a 3 phase panel.

The box circled in red is a disconnec to shut down the power to the panel next to it.

The first panel also has wiring errors in it.

I suggest that you get a licensed electrician in to have you with these issues along with the liability issues.

 

Thanks for the pics!

Here's what we're looking at: The small panel that has power is a split-phase panel. It is fed with either 120/240V power or, more likely (more below) with two of the three phases of a 120Y/208V commercial service. It looks like a small subpanel for residential use, and does not appear to have a separate deadfront. You can read the number for the breaker that's being used as a main disconnect - the 2-pole breaker at the top left - to see how much power is available there now. You can also read the label on the panel door to see what its maximum capacity is.

The other panel is a 3-phase panel. There appear to be red and black wires left in it, so my guess is that it was originally supplied with 120y/208V power. Hence my guess about the supply for the other panel. I'm not sure if it is a fully commercial panel, because I don't see that the breakers are mounted with screws, but it is a more robust panel than the one with power, and is not a compatible match for being fed as a subpanel from the first one.

You may not like what I'm going to say next. Sorry.

Your warehouse appears to have commercial 3-phase power, which is typical in a commercial district. It may be fed with a 277Y480V service, with 120Y/208V stepped down from that. The work that needs to be done is above the skill level of even an experienced DIYer. It will also require a permit, which only a licensed master can obtain. You should ask your neighbors in the commercial district for referrals to electricians that they trust, and call one or two of them to assess your needs and give you estimates.

My post overlapped with pcboss'.

 

Given the circumstances I'm curious as to where the power to that first box comes from. I'm also curious as to where the conduit coming out of the large disconnect is coming from (if it ends up in the same place as where the smaller box is fed from) .. I have a sneaky feeling they were using that three phase panel for split phase. Look closely - there is no center fuse in the large disconnect, and the upper left breaker only has two clipped wire tails hanging out of it. That breaker could've been used as the main just like in the smaller panel, because the top lugs are screwed all the way in and do not have clipped wires.

Mranderson, lets see what your meter looks like. Is there another panel underneath it? Is there a transformer anywhere?

Does your power come in from underground or from an overhead pole? If it's from overhead, let's see where the wires attach to the building.

 

It depends upon the serving utility but it IS possible that the energized panel is from a 240/120 volt single-phase service and the three-phase panel is from a separate, now-removed, three-phase service. I am not convinced that the fused switch to the left of the three-phase panel was feeding the panel, it could have been a safety switch fed FROM the panel.

 

It also depends on what he's using this space for.. If it's going to be converted into a loft style residence, a small workshop without large tools such as lathes or other large motors, or just used for storage or something, he doesn't need to go through the expense of (re)installing 3 phase.

 

I haven't seen a suggestion that the OP needs to (re)install anything. I have seen two suggestions that he needs to find a licensed commercial electrical contractor to see what he has.

I'm not clear how that would change the picture. This isn't the OP's owned residence. It's leased commercial space. In every AHJ I've ever worked with or even heard of, the only time a non-electrician is permitted to do electrical work is when that person is the homeowner, and s/he is working on her/his own residence. Then they may need to pull a permit and, in some jurisdictions, to pass a test before applying for the permit.

Or that it was bootlegged into a single-phase system. If I was a betting man, though, I'd bet on a three-phase service fed from a main disconnect in the electrical room through the 1-1/2"(?) pipe at the top into the lugs at the top of the buses.

I agree.

If the large fused disconnect was used as a main for this panel, that would have placed the OCP outside the electrical room. And why would the power have then been fed into breakers instead of the lugs?

Also, while it is difficult to tell from the posted photo, the screws in the top lugs to not appear to be screwed all the way in to me. In fact, they appear to me to be backed out flush with the faces of the lugs, which may indicate that feed wires were removed from them. Or that they were never fed. Or whatever. But since commercial power is almost always fed overhead when it isn't fed through the slab, I'm betting the feed came down the top pipe.

I also can't tell on my monitor whether the group of breakers in the top three left positions are three single-pole breakers (in which case not a main) or one two-pole and a single-pole, or one three-pole.

But let's say everything you just said is accurate. How does that change the situation? Isn't the situation still that a person who describes himself as is asking for advice on feeding and loading a subpanel in his leased commercial space?

 

Where do you see anything about leased commercial space? He said "I have a warehouse", which to me implies he owns the place. People can buy warehouses you know.. And people all the time re-purpose old warehouses or other commercial space as residential. They're called lofts, and they are highly desirable.

As for the 3 phase panel, look at the non-closeup picture. The one that also shows the disconnect.. That picture is lit from the right side, and the lugs' screw holes are shadowed, meaning they are not flush with or above the surface of the lug, they are recessed. And that is definitely a 3 pole breaker.

 

Mranderson, you need to tell us if you own the buliding and what you plan to use it for?

Please guys and gals NO, more speculative posts till he answers that question. Non beneficial posts subject to archiving.

 

WOW alot goin on here... i will try to respond to everyone.. if i miss someone let me know...


I just ordered Wiring Simplified thanks Nashkat1 & Furd


JerseyMatt I will find out tonight where the wiring is coming from and what the meter looks like.


I see JerseyMatt and Nashkat1 going back n forth on a couple things... sorry let me try to clear somethings up.

I do own the place
It will be used as a small office space with max 2 computers and maybe a radio and modem... maybe a phone charger I can't see anything else being used in there.

more pics soming tonight

I CAN'T THANK YOU GUYS ENOUGH FOR THE INPUT!!!!

 

We still need to know for sure if it is three phase. Does the supply come in overhead? Is there 3 wires or 4 wires from the pole. Please make that part of your picture list if your not sure how to answer.

 

but you don't live there and you're not planning to live there. Given that, can you get a permit to do electrical work there? Do you have that permit?

Coffee pot? OK, seriously: All of the loads you listed need single-phase power. But does the place have A/C? If so, is it single-phase or 3-phase. A picture of the inside of the service disconnect for the unit will tell us that.

And this isn't even the tip of the iceberg on the subject -- thus no DIY book.

 

The electric company may even charge less for single phase due to the difference in the way the two are metered. IIRC 3-phase the power factor is a component of the charge but not on single phase. The electricians will correct me if I'm wrong. Of course we first need to know if you have 3-phase.

 

Depends on the service. I have red leg 3 phase to my house but my meter doesn't have a power factor reading. It's just a regular 5 dial meter. I believe power factor comes into play for commercial/industrial over a certain size.

 

OK I THINK I HAVE A SOLUTION!!!!! Tell me what you think...
Before I say let me say this again..
small office - It will be used as a small office space with max 2 computers and maybe a radio and modem... maybe a phone charger

I noticed that the circuit breakers in box1 say 20amp... i calculate my amp useage and I can't see me ever using 20amps for what I need.
ok with that said

there are outlets in the area i need electric already but the wiring was cut from box2
Is it possible to just wire those outlets to box1? in stead of creating a subpanel?
And if so what type of wiring do I need to hook a power outlet to the circuit breaker?
Im looking here but not sure which is correct. Shop Electrical Wire & Cable at Lowes.com

 

Your are going to need to find out the building construction type before a wiring method can be suggested. Depending on type your options may only be coonduit or metallic cable.

 

Thanks! Now when you say "building construction type" How do I find that out and what types are there? Just so I know I am answering the question correctly. Thanks again for your help.

 

Is it a sheet metal building with no finished interior walls? Is it brick or block with no finished interior walls? Is it wood with no finished interior walls or is it one of these with finished interior walls. Is there a finished overhead that is accessible?

 

Sorry for the length, but this will help you understand construction types. Some wiring methods are only allowed in certain types of construction.

Understanding Building Construction Types | Firefighter Nation

 

Very likely. Who are you planning to hire to do the work?

 

AM
Nashkat1 - Hopefully myself if all I have to do is run a wire from the circuit breaker to the outlet.

AM
pcboss - Thanks for the info

AM
ray2047 - Its mainly painted cinderblock then the area where I would have the computer has 3 walls made of wood frame and drywall

 

1. You are adding a new circuit to an existing panel. In every jurisdiction I'm familiar with, that requires a permit.
2. This is not your residence. Homeowners can often get a permit to do electrical work on their residence, but that doesn't apply to owners of commercial space, AFAIK.

What does your jurisdiction say about this?