Who knows fuse boxes?

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I've about reached the end of my knowledge. On circuit #3 [switch] I see a black, white and ground. I believe the way the diagram lays it out that both the white and black are carrying different 120 volt legs, so that would mean that combined it's 240 Volts. IIRC; On most house wiring the white is neutral and not carrying a live load. The white wire should be marked with black tape at both the fuse box and the other end so that nobody mistakenly uses it for a neutral.

There are reasons why nowadays the ground and neutral are separated but I don't know enough to explain it properly. When the time comes to install the new breaker box, I would suggest hiring a sparky to come in and show you where to run the outlets and wiring, and then bring him back to do the final tie-in. You could also do it yourself and get the inspector to let you know whats required.

22

Oh my.

The black box with the red fuse behind it is your main, it feeds the bus bar that distributes power to all the fuses. The black box with the green fuse is functioning as the rest of the fuses, pulling power from the bus bar and carrying it to the black/white conductors (AC condenser or 240v outlet for an electric dryer / stove).

Be certain your meter and main conductors are 200 amp if you plan on using that new breaker panel.

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23

Wow - that thing is state of the ark.

The fuse numbering is a bit weird(*). Here's how I interpret it:

Numbers 1 to 4 are the central black fuse carriers. There are two individual fuses in each. Fuses 5 to 12 are the round ones on the right (5 is the top, 12 the bottom).

The pair of fuses in the central black carrier 2 are the main feed in (two separate 120V legs, one fuse for each). One leg then feeds round fuses 5, 8, 9 & 12. The other leg feeds fuses 6, 7, 10 & 11. Ideally the loads around the house should be split evenly between the two legs. (eg appliances on 5 & 6, and lights on 7 & 8) as the hand-written labelling indicates.

Fuse carriers 1 & 4 are currently unused. Fuse carrier 3 is labelled "Air Conditioning", and is probably a 240V feed (you can get 240V by utilising both 120V legs), so basically fuse carriers 1, 3 & 4 are for 240V service, and fuses 5 to 12 are 120V service fed from carrier 2.

(*) Weird to me because although I'm an electrical engineer, I'm based in the United Kingdom and we have a very different domestic electrical system here.

Anyhow, I'd recommend you get a professional electrician to check it over for your peace of mind. When funds allow, have it replaced with a new panel containing circuit breakers and if your electrical codes require it, the "differential" type breakers @Zoltan refers to above (we call these RCD here => Residual Current Device, but I believe they're called GFCI => Ground Fault Circuit Interrupter in North America).

A full rewire of the house might not be a bad idea, depending on what the electrician advises.

Note that fuses only protect the wiring from over-load (ie fire). They offer no protection at all against electric shock.
The differential breakers (GFCI/RCD) can offer "life protection" by disconnecting the supply if they detect an imbalance in the current going to and coming back from a circuit (such as might be caused by someone receiving a shock, which is a leakage of current to ground). As such, if your installation does not include GFCIs consider having them installed as soon as is reasonably possible.

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If you're going to put a new panel in definitely pull new 12/2 romex where you can. As was stated by @MarcT you definitely want GFCI, though I probably wouldnt go for the breakers themselves as the receptacles are usually much cheaper and do the same thing. IIRC You want them within 7ft of any sink and I think new code might specify you need them in bedrooms too though this might not be the case everywhere. Local codes trump NEC.

Check with the power company/electrician as well to see what your service entrance is rated for. It doesnt make much sense to put a 200A panel with a 100A service entrance. It can get expensive to pay someone to rewire your house so you might want to brush up on your screwdriver skills. Though technically it might not be legal for you to do your own work where you are (unless you are a licensed electrician) whos going to know right? Its a really dry read but pick up a copy of the NEC wherever you can and read through articles 100-300 as they will pertain most to what you will need to do. Theres some other calculations based on deration of total current and deration of wires in conduit, blah blah, box fill calc, blah. None of it really matters if you stick with some rules of thumb, which I can help you with if you decide to do stuff on your own.

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When I was a kid lightning hit our house and the fuse box exploded. It was so friggin loud and the door of the 'fridge flew open and stuff fell out. Dad had to get circuit breakers installed.

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All sorts of good information in this thread! You guys are inspiring me to see about re-running the electrical for an existing outlet just to see how hard it is. I've still got a few 2 prong outlets floating around the house that no one would miss if I find I can't do it halfway through the project. :slight_smile:

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It is easier then you think... and google/ youtube is your best friend.

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Modern houses have electrical tubing with angles that facilitate shooting wires to the end points. Old houses did not have that, many have the 90° approach. Therefore it's probably a good idea to get a cable detector thingy and map out the tubing to see what approach would be the easiest to shoot the wires.

I'm not an electrician, though, maybe there are tricks of the trade someone with actual knowledge on th subject could contribute. I redid the complete wiring in my first house, and the easiest way was to actually rip the old wiring tubes out of the plaster on the walls, and put in new tubing. New tubing can be bought prewired, it's really easy and not expensive, it comes in spools of tubing that have the electrical wires already inside, it's super fast, literally hack old tubing out of plaster, put new tubing in, fill it up, let it dry, sand it even, refinish, done.

29

you must really like guitarists

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Actually, it is pretty simple other than running new wire. If you have attic space, a look see is in order. Might be pretty easy. relatively

31

the last time i played sparky and had to rewire things i just tied the new lines to the old lines and pulled like a mad man at the breaker box ( did not have tubes in the walls so i had to tie it to the top of the old lines.) if you have tubes in the walls i would also recommend tie a piece of twine to the old line and run cat 5e or cat 6 cable after you run the new power lines. if you are unlucky then you might have one run split up to service all the sockets so you will have to go socket by socket when your running the new line. and if that is the case then it makes running the cat cable a little bit easier.

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It's not recommended to run copper Ethernet cable in the same trunking/conduit/pipes as mains power cables.

This is for two reasons:
1) To avoid RF interference radiated from the mains cables affecting the data network.
2) Safety - there is a chance (however small) of mains coming into contact with the low voltage (LV) cabling.
For example, at a bend or pinch point if the insulation on both cables is compromised, the LV cable could become live at mains voltage.

In the UK it's a wiring regulations violation to mix mains and low voltage cables in the same trunking compartment or conduit (pipe). There must be physical separation between the two.