Hello everybody,
The other day, I was thinking of a few electrical 'improvements' to my home. I decided to take a look at the sub-panel (since I was considering updating it to a newer one), which is running off of a 240 volt 70 amp breaker on the main panel and appears to be a Siemens ITE from around the 80s or early 90s, and this is what I found inside (sorry for it being blurry):


One of the things I have noticed first of all is that there is no ground wire. It appears that the neutral (the bus on the left) and ground (the bus on the right) bus are connected. So when I get the new panel (http://goo.gl/e8aWS), does that mean I'll have to wire a ground wire from the main panel? If so, what AWG? Since this is 70 amp, I'm assuming 4 AWG. Seems hard to find that kind of wire, though. I also know that it is upside-down. Just for info, the breakers are all 15 amp, except for the one on the bottom left, which is a 20 amp GFCI breaker, although that doesn't appear to be connected on the other end, so might get removed in the new panel.

Also, I will most likely upgrade all of the 15 amp breakers to AFCIs, considering they're all associated with bedrooms (yeah I know that's a lot of outlets and lights ). Should there be any considerations for buying AFCIs?

Thanks in advance.

 

Those two bars in that panel are neutral bars. If there is a bonding screw in place then they are combination bars. The bonding screw goes thru that bar and into the metal box. It looks like that sub panel is fed in pipe. The pipe would actually be considered the ground.

When you purchase your new panel it won't come with a ground bar. You'll need to order the ground bar for that panel. It comes with two screws for mounting it in pre-drilled holes.

It may be an issue pulling another wire thru that pipe now. If you were able then you would use #8 THHN wire.

I'm not a fan of AFCI breakers. I'm having intermittent trip issues in peoples homes. The idea is sound but false tripping is a problem.

The code requires them in most areas of the home today with new construction. You don't have to retroactively replace them in an existing dwelling.

If you decide you'd like the added protection they afford..... I'd recommending installing them on receptacle circuits only. This way if it trips you won't be in the dark.

 

Thanks for the response. I'll keep your advice in mind when doing this. After a quick search of the panel at the link I added in the first post, it appears that it actually comes with a ground bar. Also, is this the kind of ground wire I should be looking for: Southwire 500 ft. 8 Stranded Green THHN Conductors-20492512 at The Home Depot

And, finally, why 8 gauge instead of 4 gauge for the ground wire?

 

That wire is perfect.
According to the code ...... section 250.122 ...... a #8 ground wire is the minimum required with an over current protection device of 70-100 amps.

 

Alright, thanks for the info again. I have another issue, there's a 15-amp breaker that controls both lights and 15-amp receptacles in a bedroom, would I need an AFCI breaker for that?

 

That would depend on which code cycle has been adopted.

Simply changing a panel does not typically trigger a need to change from regular breakers.

 

Alright, I'll make sure I check on what I can/can't do. Also, I heard somewhere that whether if it's a receptacle or a light socket, it ALWAYS has to be on an AFCI-protected circuit, if it's in a bedroom, living room, etc. Is this true?

 

Again it depends on the code cycle. Earlier ones only called for AFCI protection for bedroom receptacles. It then expanded to bedroom outlets. Now it has expanded to most interior areas that do not require GFI protection.

 

Another thing: Does the neutral wire need to have the color code on it? It's a black wire right now (look in picture), so I might replace that with a color coded (white/gray) one if it does need to be.

EDIT: I looked through a few places and I couldn't find any color-coded 4 AWG THHN wire in white (all I could find was black), and I remember in the NEC that it said to somehow mark it off at each end of the wire. Is that what I would have to do, and how should I mark it off? White label?

 

#4 and larger can be redesignated with bands of white marking tape. #6 and smaller are not permitted to be redesignated by NEC code. Local code may vary. In the electrical aisle you can find packages of assorted colored tape.

 

Get the ones that are made for the panel you're installing and the right size for the circuits.

Yes, under the 2008 and later code cycles, when adopted locally. In California I'd put my money on their being adopted.

 

In the picture, there appears to be a larger black wire with white tape on it connected to the bottom of the left-hand neutral bar.

 

Also, get the combination type AFCI breakers.