I would like to update some of the wiring in my 1949 ranch home.

INFO:

There is the original wires which account for about %25 of the whole system.

A 200 amp circuit breaker box was added in 1981, but I dont think it has
ground path components.

I would like to replace some of the original circuits in my spare time. That
wiring (old braided wires) looks bad.

So here is my question

Can I replace one circuit at a time, or would I need to update the entire system?

My main concern is getting the old wires replaced with new wires.

I want to do it by code. ( Atlanta Georgia )

I know some basics about electricity, but I am no electrician.

 

Not quite sure what you mean by that. Are you talking about the main service panel ?
That may have a ground rod connected and should have a ground line to the water service.

You could post a pic or two of the inside of the panel and we could look it over.
http://www.doityourself.com/forum/el...rt-images.html

As far as running new circuits.... you can replace your old wiring one circuit at a time.

 

Actually its a 150 amp service panel. It does seem to be grounded. The nuetral bus bar has a big fat copper wire leaving the panel and it is attached to a copper hot water line.



Let me know if you need a better pic
Thanks

 

you can clearly see the old wiring on the left, and the newer wiring on the right.

 

That is one big red flag, it was never allowed to ground to a random hot water line. What version of the NEC has your local jurisdiction adopted. It is impossible to tell you the code requirements if we don't know what code is in force there. I am guessing that you'll probably be needing to add a subpanel as today's code requires more circuits than what was acceptable in 1949.

 

It is not a 1949 panel. Its a 1981 panel with lots of circuits.
My book on residential wiring says it should be grounded to a cold water pipe, with a jumper around the water meter.

As far as NEC. I'm in Atlanta. Not sure exactly what "version"of code,
but it will be a common one.

 

All versions of code are common. Joe is asking what year. Georgia is 2011. Source: http://www.nema.org/Technical/FieldR...on-Map-PDF.pdf

 

I see a 30-slot Cutler Hammer Type CH panel (can tell by the housing color and the tan breaker handles). Based on old, now obsolete rules, 30 slots was common for 150A panels. Type CH panels compete with the Square D QO series for "top of the line" in residential grade panel equipment.

You have one combined neutral/ground bar. This is fine as it's the main panel where the neutral and ground are bonded (ground wire connected to the neutral bus). The neutral bar should be connected to the panel housing by a bonding screw (often colored green).

I can't see the wires you mentioned well enough, but I assume they have a braided cloth jacket and two rubber-insulated wires inside.

If there is room, you can connect the ground wires of any new cables to the neutral/ground bar. If there is no room, you can add a ground bar to the panel just for landing new ground wires. Eaton-brand (parent of Cutler Hammer) ground bars can be found at big box stores in sizes ranging from 5 slots to 21.

 

Being a large city I suspect that Atlanta requires you to take out a permit for electrical work. This permit could be for a single branch circuit replacement or for multiple replacements. The cost of the permit is probably based upon the dollar cost of the job so one for multiple circuits would probably be more expensive than a single circuit permit.

All work under permit needs to be inspected and permits have time limits as well. Six months is a normal time limit but one year permits are not unheard of.

To be legal you MUST have a permit (and inspections) if one is required in your area.

 

Another thing to consider for proper grounding and neutral set up of this panel.

Is this the main disconnect for the service; I am not just referring to the fact that their is a main breaker in the panel. What we need to know if there is a disconnect for the service before this panel. If so this panel must be converted to a sub panel set up requiring you to separate the ground and the neutral bars.

We are just assuming this is the main disconnect for your service. Just because there is a ground wire presently going to a water pipe does not mean anything. Verify that this is the main disconnect for your service first especially since number one you want to go by code and number two if you did not install this breaker panel.

Yes, I see that the main service entrance cable is a SE cable but that does not mean that they did not use the incorrect cable as the service entrance coming from a disconnect prior to it and should have brought over two hots, a neutral and a ground wire utilizing an SER.

 

You need a newer book. Assuming this is the main panel with first OCPD, your service needs a ground rod connected to the neutral bus with #6 copper wire, the GEC. It also needs a GEC (#4 copper or #2 aluminum) to within 5 feet of where the water service enters the house, looped and clamped around any meters or pressure reducing valves.

Lots? I only see 3 available circuits. Is 3 available circuits enough to provide 2 small appliance branch circuits at the kitchen countertop? Is 3 available circuits enough to provide a dedicated bathroom receptacle circuit? Is 3 available circuits enough to provide dedicated dishwasher and furnace circuits. Have you considered a dedicated smoke detector circuit? You didn't mention what appliances you have, there may be more dedicated circuits required. My point is, today's code is drastically different than the 1949 codes. You are also going to need to have multiple AFCI protected circuits, numerous GFCI protected receptacles and weather resistant GFCI protected receptacles outside. Most receptacles will need to be tamper resistant as well. You really need a new book.

 

Thank you so much for the info.
I feel better knowing that at least some circuits are grounded.

 

CasualJoe.
That really gets to the heary of my question.
Lets say I wanted to replace ONE the old braided wire circuits, and add a smoke detector circuit( which is required here)

The main idea here being to update my system in my spare time.

Would I need to submit a plan and get a permit for just what I am updating? Would the inspector come out and check only the new wiring. I dont want to open up that infamous "can of worms ".

I do want the work I do to be code approved.

My book is one of those Stanley home improvement books from home depot.
I would love a much more detailed book aimed at folks like me. Any suggestion?
I thought about getting a code book, but it probably would not help a novice like me.

and by lots of circuits I mean that my service panel is way larger than the other homes' in my neighborhood. Its twice as large as some of the others I have seen.

Thanks!

 

(after getting your permit if needed)

You may replace or upgrade circuits one at a time or a few at a time piecemeal starting at the panel and working outward.

The remains of the old wiring continuing on may be connected to the new wiring back to the panel (inside appropriately sized outlet boxes or junction boxes) until your next work session.

I personally would not leave upgrading work on existing switch, fixture, and receptacle locations un-energized awaiting inspection. In some cities no permit is needed for this.

Adding a new circuit may or may not force an upgrade of the panel and/or upgrade of the utility service from the street. This is determined by the results (total wattage) obtained by the "load analysis" procedure in the National Electric Code. Otherwise adding a new circuit does not require upgrading of existing things.

The fat copper wire (bonding jumper) to the hot water piping grounds the hot water piping to the electrical system ground however good that ground is but does not count as grounding the electrical system via the plumbing system and cold water pipe grounding electrode. A similar fat copper wire (as a grounding electrode conductor) installed from panel neutral bus to the cold water pipe as described further above needs to be added. In addition a grounding electrode conductor (max. #6 copper for this one) from the panel neutral bus to a pair of 8' ground rods at least 6' apart is needed if not already there to complete the grounding electrode system.

 

I would definitely NOT recommend that you get a copy of the National Electrical Code (NEC) as it is a difficult read for a lay person unfamiliar with the profession. Even the NEC Handbook, which offers commentary explaining SOME articles and paragraphs is NOT written for the lay person. Besides, both of these publications are rather expensive.

What I DO recommend is Wiring Simplified. Wiring Simplified has been in continuous print for more than fifty years and is the "bible" for DIY electrical work. It is revised every three years to coincide with the revisions in the NEC and in addition to explaining HOW to do the work it also explains WHY it is done in the manner prescribed. Wiring Simplified is sold by many on-line booksellers as well as often being available in the big box mega-mart homecenters and even local hardware stores. The cost is nominal, $6.95 at my local big box and almost always less than $10. It usually will NOT be found in the books and magazines section of the store but in the electrical aisle.

One thing to always remember is that all codes are local; the model codes such as the NEC (and any building, mechanical, plumbing, etc. code) has no power of enforcement but is just a guideline of MINIMUM standards promulgated to ensure safety. It is ONLY when enacted into law by a state, county or municipal legislative body that the code becomes LAW. The enabling legislation has the power to add to or delete from the model code and what may be allowable (or prohibited) by the model code may be just the opposite in the local code so you need to find out which code has been adopted AND if there are any additions or deletions from the model code.

 

Here is a problem you'll probably run into. Let's say you have picked a circuit to replace. When researching what the circuit feeds it most likely will feed a lot more than you want to put on one circuit. For instance, it may feed all bedroom receptacles, lights in those bedrooms and maybe even something in the basement and even maybe a bathroom light. I think the new circuits should be laid out a little better than that so the new circuit may only cover the bedroom receptacles. I also like using separate circuits for just lighting. It's also best practice to dedicate a 15 amp circuit for all your smoke detectors as they are required to be interconnected by most jurisdictions.

Those amendments to the code that Furd has mentioned are very important. I'd recommend contacting your local building department and having a discussion with them about the local code requirements and how they want to handle the permits/inspections.

 

Thanks so much for the detailed info. I will definitely get me a copy of "wiring simplified".

And, Casual Joe, your absolutely right about the original wiring.
The first circuit has sooo much on it. It seems as if there was no plan
when originally wired up. It seems like nearly half the house is on that first circuit.
I started putting together a map of that circuit. One of the upgrades I wanted to tackle first is to separate that circuit into a more appropriate configuration;
I'm no electrician, but I would have done a more organized set up;
Putting the lights on one circuit, and receptacles on another etc. Its been working
for 65 years like that, but I worry about the load on that one circuit. If there
were something plugged into each of the receptacles on that circuit, it could
be overload easily. Its lights , bathroom & ceiling fans, and receptacles all over the house on that first circuit. Why would a professional do it like that? Even if there were no codes at the time,
it seems like a real pro would have organized it better. No?

Thanks everyone!
I'll post back after I electrocute my ass a couple times.
And dont worry, I will have a real electrician look at stuff before I dive in.
And after! I'm not into endangering my family with faulty cut corner wiring.

 

My house was also built in the '40s. Originally this house had two 120 volt 15 amp circuits; one for East lights and receptacles and one for West lights and receptacles. Things are done much differently today.