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dubson
Jan 18, 2008, 02:29 PM
I bought an old house with an electrical system which should have burned the house down in about 10 different ways, so I'm replacing *all* of it (the service entrance had already been condemned, maybe I should take a pic before I remove it).

I am doing all the work myself, and it's been trouble finding info on the service entrance, but I think I'm done. I installed 150A service. Outside is the meter, and directly behind it inside the house is the breaker panel. The service entrance wires are 1/0 for the hots and #1 for the neutral. Finding specifics on how to wire the breaker panel is difficult, so I used some thinking but I'm not sure if this is correct. The ground terminates in the meter box, per local utility specs, so I figured I should jumper the ground buses to the neutral buses and I used leftover #6 wire as shown. Is that correct? Anything else look wrong in the panel or elsewhere? Thanks!

http://www.venamous.net/electrical/breaker-d.jpg

http://www.venamous.net/electrical/meter-c.jpg

http://www.venamous.net/electrical/outlet-c.jpg

My horrible house (before I bought it): pictures of old house in bells (http://www.venamous.net/house/)

Stratmando
Jan 18, 2008, 03:15 PM
You should have a Ground rod, and connect to meter(small lug at bottom of center wire lug) Remove Jumper in electrical panel between the Neutral and ground. Be sure neutral Bar is isolated from panel(No screw through neutral buss to panel back)You May be required to have a disconnect outside. Also remove the little jumper between the right Neutral bar and the right ground bar.
The quad receptacle below Panel needs a Ground screw and wire in the top right inside of the box, then connect to the 2 bare copper with wirenut. You may need to remove the insulation from the romex in conduit, But will not cause overheating in this case.
When you make connections to panel, you should try to keep wires square within the panel.
It is currently short as wired, but can be easily corrected by moving to a lower breaker location, and a lower buss connection for the ground and neutral, connect both to the right side of panel, instead of 1 left and 1 right(plus you have wire to do it).
I start at the top of the panel with the bigger breakers, Range, Central Air, Dryer, Water heater and any other 240 volt stuff, then the 120's.
I would pull off a panel cover and see how it should be wired. A couple of panels if you can as there is a possibility of running into a bad example. Good Luck
Others will provide additional info.

tkrussell
Jan 18, 2008, 03:58 PM
Rarely, Strat is incorrect, but regarding the grounding at the meter and panel, in this case, he is incorrect.

Grounding of the neutral may occur at two locations, in the meter, and/or in the panel.Do not break the connection of the neutral and equipment ground in the panel. What I see is fine.

I will say, if the threaded nipple between the meter and panel is metal, then a bonding bushing, AKA grounding bushing, is required at one end. If plastic, the n disregard.

Since the panel appears to be "Back to Back" of the meter, the Main Breaker is fine in the panel, and one out at the meter is not required.

Remove the sheathing from the Romex cable that is in the panel, up to the entry point of the connector.

The minimum length of wire in an outlet box is 6 inches, you have two cable each with what appears to be 12 in. The wire can be longer than 6", but don't need to overdo it.

Strat is correct in that the bare equipment grounding wire must connect to a green machine screw threaded into the back of the metal outlet box.

Is that a connector with a locknut on the ends of the metal flexible conduit? Hard to tell, if it is a connector with a locknut, sure looks funky.

Stratmando
Jan 18, 2008, 06:34 PM
They like an outside disconnect down here, a Fire Thing I think.
I have pulled a neutral through the neutral lug in disconnect and be Continuous from meter without breaking conductor(skinning insulation/tightening 2 allens), To Electrical Panel. Inspector wanted me to cut the Neutral, Couldn't be continuous. A broke Neutral is worst thing you can have(Except maybe a broke Ground). A broke hot you only lose power. Also had one tell me Backwiring of recepticles is as good as around screw, I disagree. Years ago, had one say for Christmas he wanted something in an envelope, Nothing in a Bottle?
We have to have a disconnect.
I would also bring right hotleg up the left side of panel?
As far as grounding both, I ground 1 point? Habits?

dubson
Jan 20, 2008, 01:48 PM
Stratmando: I do have a ground rod, and you can see the wire terminate in the meter. I don't need a disconnect outside here, but from what I've read it sounds like a good idea anyway. When I redo the siding I'll probably add one. I'll remove the romex sheathing.

I've had an inspector look at it now, and he sees no problem, but other opinions are nice as I know that there's sometimes more than one way to do it, and perhaps the inspector is an idiot.

I'm leaving the jumpers between neutral and ground. Not counting those jumpers, it looks the neurtal bar is isolated from the panel, but this is now a moot point.

I put the breakers there because only those two slots were already open on the panel cover. I'll put the bigger breakers up there later as that's the way I'm used to seeing it as well.

I thought about grounding the box to the outlets, but this didn't seem necessary to me because everything is already grounded. The inspector didn't mention anything, and I didn't have a screw. I don't see why it would hurt, though, so perhaps I should do it anyway.

I'd love to look at a few other panels, but I don't know anyone around here. I just have the old panel as an example: http://www.venamous.net/electrical/old-panel-b.jpg ;)

dubson
Jan 20, 2008, 02:36 PM
tkrussell: thanks for verifying that the grounding is correct. That's the part I made an educated guess on because I couldn't find explicit information on it.

The nipple between the meter and panel is metal, with grounding locknuts on each side, and plastic bushings on the end. Is that what you're talking about?

It's a "screw in connector" with a locknut (iiuc) on the flexible conduit ends there's a picture of it in my black&decker electrical book. An older home construction book I have by george nash (the only source I've found on how to do a service entrance other than the electric company requirements to the meter) shows some other type of connector which attaches on the outside and requires a plastic piece on the inside to protect the wires from the conduit end.

Thanks for your other information. For fun, you can tell me how many things you can find wrong with the previous service entrance (assume current code, though I imagine there are things which were never to code). There's five things that I really don't like about the service entrance alone. Beyond the panel, there are many, many more (like the 30A circuit connected to one 15A outlet which had a 15A 6-receptacle adapter attached [they did use 10/2 wire, so they "knew" what they were doing], and the NM wire attached to the outside of the house, and the flying splices with only electrical tape on that exterior NM wire).

old service entrance (http://www.venamous.net/house/oldservice/)

tkrussell
Jan 21, 2008, 06:05 AM
Well, since you passed inspection seems your good to go.

If the locknuts are "grounding" there should be a set screw to drive into the nipple.

The connecting the ground wire to the metal box and the outlets is Grounding 101. This is not done ONLY if the outlet device is positive grounding at the screws, which usually are only "Spec Grade " devices.

Yes, afterwards I saw that is was a connector that inserts into the flex.

KISS
Jan 21, 2008, 07:16 AM
Am I seeing things that aren't there? It looks like there are two large lugs on the left. One on the neutral bar and one on the ground bar. Wouldn't that be the place to jump with a larger wire and also not have the ground jumper on the right side of the box?

Stratmando
Jan 21, 2008, 07:26 AM
KISS,
I would pull a ground from Meter to Panel. And run Ground screw through Neutral bar to
Ground, and use no little jumpers. It passed inspection?

tkrussell
Jan 22, 2008, 07:09 AM
Strat, if you did pull a ground with the neutral, you would have two wires in parallel for the neutral between the meter and panel.

Stratmando
Jan 22, 2008, 08:07 AM
In that case I would keep separated in panel, Ground would be ground, neutral would be neutral. All Homes I have done is usually conduit running to Panel location, Don't get any Back to Back. Plus the ground works better on bonding bushings? I always pull separate ground and neutral. It may be Overkill?

ceilingfanrepair
Jan 22, 2008, 09:41 AM
i bought an old house with an electrical system which should have burned the house down in about 10 different ways

I went to look at your pictures to see some of this, but couldn't find any. Old screwy wiring facinates me. There's a contractor's forum somewhere on the web where they post pictures of horror stories.

Any old ceiling fans in that house? :)

dubson
Jan 22, 2008, 03:39 PM
ceilingfanrepair: yes, there are several old ceiling fans. I don't know if they work, of course. The pictures are there; I just rechecked the link: old service entrance (http://www.venamous.net/house/oldservice/)

ceilingfanrepair
Jan 22, 2008, 03:40 PM
I think I was looking at the wrong link.

Any pictures of the ceiling fans?