Electrical Circuits

Electrical Installation Help

Hello again - Velvet Elvis :)

Sorry if some of this stuff I state here is already familiar to you... :o

You mentioned:
"I'm not required to have a licensed electrical contractor... only that I pass the city's electrical code test"

This is very common in a lot of municipalities outside of Philly.

My Mom lived in North Jersey, and although I'm BOCA certified as an Electrical Inspector, I didn't need to hire a Licensed Electrical Contractor to install a new service for her house. However I needed to have it inspected by the township Electrical Inspector. He and I were members of the same organization.

As mentioned: 16a x 120v= 1920watts OR 1920 watts / 120 = 16 amps :D
Hair Dryers are considered to be on only for a short while,
so it wouldn't be necessary to install a dedicated circuit
or ONE single receptacle just for the hair dryer.
Although since 1996, the NEC DOES state that all
NEW bathrooms shall have a GFCI dedicated 20 amp
circuit to feed that bathroom. And of course also
on that circuit you feed an exhaust fan too.

As I mentioned before, everything is 'relative' - it shouldn't be too difficult for a willing knowledgeable homeowner to run a few circuits. From an inspector's view, we see only the worst case scenarios - I'm sure there are guys who can be self-taught and do an adequate job.

Go ahead and dive right in there - it appears you have common sense, respect, and caution for 'live' 'hot' circumstances ;)

Your Sub-Panel (if installed properly), should have been fed by a 4 conductor service cable known as SER cable. In it's jacket should contain, 2 black conductors, one white conductor, and a braided aluminum ground. Correct?
How many spaces are in the sub panel? Hopefully enough for your studio (as I pointed out earlier)
More importantly: any branch circuits that are installed in that sub panel, should have all of it's grounds (sometimes bare copper), connected to the 'BONDED' side of the bus in the panel. The neutrals however should have all of it's (white jacketed wires), connected to the 'UNBONDED' neutral bus in the panel.

GROUNDING IS VERY IMPORTANT - Life Safety Issues, and if not properly done, can create line interference, 'HUM' etc..
And use 12/3 romex for insulated, separately grounded receptacles (as I mentioned above)

You can handle it :)

And as someone else pointed out, if your sub was already installed by a contractor, check the nomenclature (marking) on the jacket of the cable to see if the size wire matches the overcurrent device (main breaker), that feeds it from the main panel ..... and assuming that the FIRST panel was grounded properly, than that's all the grounding that you'll need for your sub-panel. For a 100 amp sub panel, the feeder installed should have been 4 conductor no. 2 SER cable. For a 60 amp. sub panel, the feeder installed should have been 4 conductor no. 4 SER cable.

The 100 amp. SER cable should have been protected by a 100 amp. double pole breaker in the main panel. The 60 amp. SER cable should have been protected by a 60 amp. double pole breaker in the main panel.

c7sus mentioned:
"I don't know if you can buy a single-phase sub-panel. I've never seen one."

4 conductor SER service cable is made specifically for 'SINGLE PHASE' Residential Sub Panels (read my explanation above)
Many times larger homes with add-on construction (additions, garages etc.), have single phase sub-panels installed :cool:

Keep me posted, and I can help - I have a large data base of diagrams etc.

Best Regards
Michael Fraticelli
ROCKON@ucwphilly.rr.com
 
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What you're talking about is single-phase 240.

I'm talking about single-phase 120v. Never seen one. My GUESS would be the feeder is sized for a 60a- 240v subpanel. Those are pretty common.
 
Single Phase 120 Volt Sub panel - No such animal - Not a good thing :(

Hello :)

Actually - (let me explain), to even employ such a sub panel, (if it existed), would be introducing an opportunity for an UNBALANCED load within the house main panel ... :confused:

Know what I mean?

All UL approved manufactured Sub Panels have either direct bus terminals, OR an already installed main double pole overcurrent device (breaker)

Perhaps it's best to allow Velvet Elvis to get back to us with EXACTLY what he has right now (in regard to his sub-panel)

As I understand it, he said he had a sub-panel installed spcifically to handle
the load of his studio?

I'm prepared to help him - and if he's reading this, it could help greatly if he had some photos to upload. :cool:

I'm not sure if he's able to do create illustrations something like these on this post:
https://homerecording.com/bbs/showthread.php?t=132504

http://home.ucwphilly.rr.com/livesound/7a.jpg < My old Panel
before I tore out the garage door

http://home.ucwphilly.rr.com/livesound/14a.jpg < My New Panel which is a nifty 30 space 100 amp residential panel. *Most 100 amp residential panels have only 20 spaces.

http://home.ucwphilly.rr.com/livesound/16a.jpg < My New Panel

Best Regards
Michael Fraticelli
ROCKON@ucwphilly.rr.com
 
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Yeah. I know what you mean. That's why I was saying I'd never seen one.

Obviously, for somebody that just needs 2 or 3 20a circuits for a basement studio, I don't think there's any problem whatsoever with putting all three circuits on the same phase. Depending on usage and how the rest of the circuiting of the house is laid out it might be necessary to swap a couple branch circuits in the main panel to the opposite phase for load balancing purposes. When I mess around with recording I wind up shutting everything else in the house off anyway to cut down line noise. Who needs a reefer compressor pump kicking in during a take?

Putting your lighting on the opposite phase is an option. But I'd keep my outlets all on the same phase regardless of how many circuits I wound up using if it was possible.
 
Guys,

I truly appreciate the help... and yes, I will gladly get you all the information I can.

The basement subpanel is not in existence at this point, only the wire drop.

It look like the wire says AWG 7 on it, but I've never seen that before (its hard to read it)

It is a three conductor wire and it says "NM6 600" Volts on it.

I can try to take some pictures later today, but I'm trying to work up the floor plan to turn in to the city.

Velvet Elvis
 
Let me add to this and try to clarify.

When the house was built, because of where they located the main panel, I have no way of getting new circuit to it. Its on the outside wall of a garage with no access from the basement. The only access was from the crawl space of the second story coming down into the garage, but now that the second story is finished, you can no longer access those areas either (besides, running wire from the basement up to the second story and then back down to the garage seems stupid.

So... seeing that they had done this, I said "I can't wire my basement" (which currently only has 6 pull string lights and two outlets)... and asked them to add a way for me to put a subpanel in the basement so that when I finish the basement, I can run all the wiring to the subpanel.

The subpanel will need to handle two bedrooms, a bathroom, a home theater (nothing fancy), an excercise room, a pool table room and then the rooms of the studio.

There are mechanical things in the basement (air handler, sump pump, water purifier etc) but they are all wired to the main panel in the garage, as they were done as the house was constructed.

I assume I could put a pretty substantial box on this subpanel line and be able to easily cover all of my circuits?

Velvet Elvis
 
Yes, you can put a subpanel to handle all of your needs. I don't recall what the NEC says, but I believe a subpanel should only be about half (or so) of what the mains are. So if you have a 200A main breaker, you have about 100 amps to play with on a subpanel.

Also, never say you can't run electrical from one point to another. There always is a way, its just a matter of how. For example, in your situation whereas the panel is "way over there" in the garage, and your sub panel is "way over there, not near the garage", you can run conduit across the garage ceiling along the perimeter of the garage space (ceiling and wall joints) so its not intrusive into the garage space. Then into the wall, down the wall, through the footer, into the basement assuming the basement is on the other side of the garage, like mine.

Another option is to dig a trench, and bury it below the frost line, and enter the house in the basement directly. Plastic conduit is better for this because you can seal it easier with the glue - waterproof mains are a good thing. Just don't dig it up later by accident :)

Going across an attic is not a big deal as it sounds like you have done either. All very doable. This is where electrician's drill bits will help you. They come in 3, 4 and 6 foot lengths, from about 1.5" diameter and down. You can buy extensions too, making for a really long drill bit. Thats how I ran electricity from the main breaker "way over there" to the studio "way over here". Pulled down the nasty basement paneling, ran conduit across the top of the wall, and put the paneling back. Then for the vertical, I drilled from the attic all the way down to the basement, and ran conduit up in 8' lengths. Plastic conduit is flexible, so I had to bend it slightly to get it in, push it up, then glue on the next piece. Then glued on the elbow, tucked it all nicely, glued the elbow to the cross conduit, and covered that with nasty paneling. You'd never know its there.

Also, if you surface mount the conduit, you can cover it with a piece of 3" or 4" angle moulding and you don't even have to monkey with the walls. As long as its in conduit, you can hide it very easy, if you're creative.

Thats how I brought 60 amps up to my studio. I used a 100A sub panel, but the main is a 60A breaker and it has six breaker slots, three of which I filled.

Sounds like a pain in the butt, and it is, but once you do it, you're in good shape.

I also ran through a pair of interior, non supporting walls, one above the other, a 3" diameter plastic conduit, which is how I snaked massive quantities of cat-5 from the basement phone switch/computer network racks, throughout the house. Was much easier to run it all through the attics to reach the second floor, and along the basement ceiling for the first floor. All tied back to a central location.

Shoving 3" conduit through a wall is a PITA!
 
frederic,

It is indeed a 200A main panel.

What I don't get (and I'm showing my ignorance), is that I counted the circuits on the main panel... and the breakers total 565A...

Huh?

Velvet Elvis
 
A couple of the factors that go into sizing conductors for electrical circuits are continuous or non-continuous loads, as well as the length of the devices from the panel.

You really should spring for a code book. The new ones are just coming out. You might be able to find a 2002 NEC codebook on sale somewhere. Your jurisdiction will likely be using the 2002 code for at least another year. Also check for state and local codes. If you have an electrical permit the issuing jurisdiction should be able to give you a copy of local code that applies. But you'll have to buy an NEC. Check out Articles 100 through at least Art. 310.

Just for clarity's sake, you have three insulated conductors and a bare ground in your subpanel feeder........ correct? And they are either AWG#7 or possibly AWG#6.

In order to know how many volt-amps you have available you need to know the length of the wire. If you already know that it's less than 100 feet long, cool. Otherwise, it may be marked on the outer sheath. There won't be any "ft" or other suffixes. Just like ----12345---- and hopefully a different number on the other end, like -----10101--------- and the difference of the numbers is your length. The length and wire size combine to tell you the rated ampacity of the conductor and insulation.

Gotta run. More later.
 
c7...

From what I could tell, there were three TOTAL wires that were insulated individually in the sheathing. I could not see another ground wire , but it could very well be there, as I was just looking at the cut end of the cable.

Yes, I believe it is AWG#7.

And yes, it is well within 100 feet. My guess would be more like 30 ft from the main breaker to where the wire is located in the basement.

Velvet Elvis
 
Velvet Elvis said:
frederic,

It is indeed a 200A main panel.

What I don't get (and I'm showing my ignorance), is that I counted the circuits on the main panel... and the breakers total 565A...

Huh?

Velvet Elvis
Click to expand...

200A is the rating of the main breaker (based on the size of the supply wire), not the max rating of all circuits added together, which are based on each circuit's wiring. I don't know the code, but the boxes are built with a fixed number of breaker slots to avoid problems, and your setup sounds typical.
 
Velvet Elvis said:
frederic,

It is indeed a 200A main panel.

What I don't get (and I'm showing my ignorance), is that I counted the circuits on the main panel... and the breakers total 565A...

Huh?

Velvet Elvis
Click to expand...

Uh-huh!

You have two levels of protection.

20A breaker, for a particular circuit (for a bedroom), so you cannot draw more than 20A through the feed for that bedroom. Turn on an air condioner, the stereo, all the lights, and run a hair dryer and you'll see why not :) The 20A breaker protects the wiring in the wall to that bedroom in this example.

The 200A breaker in the mains, protect the mains coming in, to 200A. Even though you have 500+Amps of breakers, you obviously cannot draw all that current from the 200A main breaker.

My house has a 100A main breaker, and about 360A worth of breakers. This actually presents a problem for my wife and I, as I have 60A in the garage for various power tools. My plasma cutter draws 40A at full speed, and requires my air compressor to feed it air, and that unit draws 12A. So off the mains, thats 55A of power thats now unavailable. If my wife is blow drying her hair (15A) and the coffee machine is going (8A) and the air conditioner in the living room is going (14A) and the pool filter (10A) etc etc, the main breaker will flip, even though all these individual circuits aren't overloaded. But their use combined, overloaded the mains. Because of this, I've replace the main breakers once a year whether it needs it or not, to ensure they are always in new condition, because this does happen quite a bit.

Of course I should just update my electrical to 200A and not think about it again...

Hope that helps.
 
A few quick easy facts!!!!

Hello again Velvet Elvis... ;)

My name is Mike. You may recall that I mentioned I'm a Licensed Electrical Inspector (City of Philadelphia - 28 years). I previously gave you some info in this post.... :)

All the contributors have given out pretty good advice so far...

I see here that in your situation apparently your township allows 'you' the homeowner to do your 'own' work. Well that can be a savings to you, but as I've also read here, it can also raise a lot of questions for you too! :eek:

Having been exposed to so many different installation scenarios, technical seminars, and continuing education for me, please allow me to help. First off (not to discount the NEC, or the other contributors), I think your questions can be answered by less technically involved statements or suggestions. It's difficult enough to attempt the basic installation stuff without having to spend a lot of time regarding theory.

So let's go! :D
You mentioned:
"From what I could tell, there were three TOTAL wires that were insulated individually in the sheathing. I could not see another ground wire , but it could very well be there, as I was just looking at the cut end of the cable.Yes, I believe it is AWG#7"

Ok - well it sounds like (in trade terms), 6/3 SER cable OR to simplify it,
60 amp SER cable. But just what does that mean? :confused:

The jacket (as you pointed out), has 3 insulated conductors, and if you look closely, a bare braided possibly 'aluminum' ground? Correct?
Can you see if the insulated conductors are COPPER or ALUMINUM?

If as you say, the nomenclature, (the labeling, says #7), then it's possible it may be 6/3 'Copper' That's even BETTER yet - But it still means that you have already installed 60 amp SER cable! (Properly intended for a 'SUB PANEL') :D

NOW - :cool:
As my other replies pointed out, you now need to get a '60 amp subpanel' to connect at the other end .... don't worry about the length of the cable - I knew you'd already be UNDER 100 feet.

Bear in mind, that subpanels come in various capacities:
6 space
8 space
12 space

They also come with or without a 60 amp double pole main - And it's perfectly alright to have protection at both ends. (Main 60 amp breakers in both your main 200 amp panel, AND another in your sub-panel). I also replied previously, to be aware of PROPER GROUNDING my freind!!! :) Subpanels require ISOLATED connections for all NEUTRALS, and BONDED connections for all GROUND conductors :D
But just what does that mean? :confused:

Well, if you look in your new sub panel, you'll see #2 bus bars (connection bars). One that 'YOU' will BOND (i.e. connect to it's metal enclosure) for bare GROUNDS from your branch circuits. And the other one is ISOLATED for neutrals (white wires from your branch circuits) EMAIL ME ANYTIME FOR HELP! :D

Please understand that as you pointed out, you ALREADY have a 200 Main House Panel - (a 200 amp main service). correct?
If so, YOU GOT POWER TO SPARE DUDE! - Don't worry!!!!! ;)

Sooooo get AT LEAST an 8 space sub panel!!!!!!

As my other replies pointed out, make it easy, and ask yourself what are your needs in your studio? For example, are you going to have 220 volt electric baseboard heat? How many circuits (based on my previous post), are you going to need???? If you don't need baseboard heat, and if you don't need any 220 volt circuits for air conditioning units, then YOU'RE GONNA BE JUST FINE! :D

I can help you with fishing, snaking, connecting, cutting, or ANYTHING :cool:

I noticed that you don't have an 'email option' in your profile ....

PLEASE EMAIL 'ME' ANYTIME MY FREIND! :D

Best Regards
Michael Fraticelli
ROCKON@ucwphilly.rr.com
 
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