Main panel replacement plans

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  #1  
Old 08-29-15, 12:17 PM
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Main panel replacement plans

I'm replacing my old 200-amp Federal Pacific panel (from 1975) with a Square-D Homeline (unless somebody convinces me that QO is worth it).

Here's the Federal Pacific panel I'm replacing:
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Some comments on the picture:
- There's no main breaker!
- A 70-amp breaker goes to an external Federal Pacific subpanel for my two A/C units.
- 30-amp breaker is for clothes dryer
- 50-amp breaker is for oven
- 70-amp breaker in the middle of the box is wired to isolated bus bars in the bottom half of the panel, and that's where my 11 branch circuits are located
- I have an existing grounding wire bonded to the plumbing at the hot water heater, but no external grounding rods.

Some concerns with the existing wiring:
1. Although my house wiring is copper, it looks like the wires from the meter are aluminum. Do you agree? If so, do I need to replace these? (That seems not safe for me to do since I'd have to work in the meter box.)
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2. It looks like the wire to my oven has experienced some oxidation. Can I just cut the green end off and strip the wire again? If not, what's the solution? Re-running this wire is not feasible.
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My plan:
1. Submit permit application.
2. Remove drywall and prep area as much as possible before disconnecting power.
3. Install 8' grounding rod outside and run copper wire through wall below existing panel.
4. Schedule power company to pull meter. Schedule inspector.
5. Run extension cord to neighbor's house for lights/fridge.
6. Power company removes power.
7. Label all circuits.
8. Disconnect all circuits and remove old panel.
9. Install new panel.
10. Install all circuits on the same sides as they are now with the same breaker sizes that I have now.
11. Pass inspection.
12. Power company restores power.

Am I missing anything big?

Additional questions:
1. The Homeline panel is aluminum. Will I need anti-oxidizing compound anywhere in the box if my wiring is copper?
2. Am I required to use AFCI breakers?
3. In the new panel, what size copper wire do I use to bond the neutral and ground bars?
4. When running the copper wire for my new grounding rod, will the copper wire just simply exit the house about 2 feet above the ground, run down the brick, and go into the ground? Or do I need to add conduit for this wire?

Thanks for your help!!!
 
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  #2  
Old 08-29-15, 12:35 PM
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Lots of questions.... make several replies to get to them all.

That is a Federal split bus panel. You technically have three main breakers there. One for the lower section, one for the oven and one for the clothes dryer. I was never a big fan of that type of panel. That's one good reason to change.

The Federal breaker problems is another good reason to upgrade.

I don't really know what the difference between Homeline and QO is but as an electrician I always use QO. The price difference is not substantial.

The wires that are oxidized can be cut back and re-stripped.

Aluminum service wiring.... from the panel to the meter is very common. That cable should have NoOx on it at the main breaker.

1. The Homeline panel is aluminum. Will I need anti-oxidizing compound anywhere in the box if my wiring is copper?
No.

2. Am I required to use AFCI breakers?
You are not required to upgrade to AFCI during a panel replacement.

3. In the new panel, what size copper wire do I use to bond the neutral and ground bars?
The new panel comes with a long green screw that bonds the neutral to ground. You can get an additional bar for just the grounds which would be bonded by the mounting screws.

4. When running the copper wire for my new grounding rod, will the copper wire just simply
exit the house about 2 feet above the ground, run down the brick, and go into the ground? Or do I need to add conduit for this wire?
Protection is not required. Clamps to hold the #6 wire neatly to the wall is a good idea.


This may not be a one day process. The inspectors give a broad range of inspection times and sometimes come late in the day. The power company needs a cut-in card (proof of passing inspection) and they will be in no rush to reconnect you. So that this may be a two day process.

 
  #3  
Old 08-29-15, 12:58 PM
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You should label the circuits before loosing power.

Once the meter is pulled the power is gone.

Plan on two ground rods at least 6' apart.

The copper oven wire looks like it got wet. A light wire brushing should remove corrosion.

Aluminum conductors are safely used to feed panels everyday.
 
  #4  
Old 08-29-15, 01:29 PM
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Best to rent a generator before you do it or consider hiring an electrician. Unlike the home owners electricians can get a way with doing a temporary connection and could probably finish in a day.
 
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Old 08-29-15, 01:56 PM
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Wow, thank you so much for the excellent responses!

I will re-consider a QO panel. I priced it out (with breakers) at $270 vs $170 for Homeline. The breakers cost 2x. Biggest difference I see is that QO is copper and Homeline is aluminum.

I will install 2 grounding rods, spaced 6-feet apart connected to a single #6 copper wire.

Good point in planning for a 2-day install. I'll be sure to do it mid-week rather than a Friday just in case.

Thanks again!

Additional questions:
1. Instructions I've seen say to install breakers starting at the top of the panel and work down. Is that a requirement, or is it just to look pretty? I might like to leave room at the top for a whole-house surge protector or a new 240V car charging outlet.
 
  #6  
Old 08-29-15, 02:11 PM
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You can put the breakers wherever, top or bottom. . You can even leave spaces open for future use.
 
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Old 08-29-15, 02:14 PM
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QO also gives you the Visi-trip indicators which are orange flags to show a tripped breaker quickly.
 
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Old 08-29-15, 02:23 PM
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Like PCboss said you can put the breakers wherever you want but the length of the existing wires will dictate the placement also. You don't want to have to extend a lot of wires in the panel if it can be helped.
 
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Old 08-29-15, 02:43 PM
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Circuits can be extended if needed.
 
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Old 08-30-15, 07:41 AM
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> 4. When running the copper wire for my new grounding rod, will the copper wire just
> simply exit the house about 2 feet above the ground, run down the brick, and go
> into the ground? Or do I need to add conduit for this wire?

Code defines that ground is necessary for human safety. And defines what is minimal (ie why two copper clad ground rods). But ground also serves a second function. It is the only device that does protection for household appliances. Length of that connection and how it is routed determines whether a 'whole house' solution will be effective or ineffective.

For example, if that ground wire is inside metallic conduit, then protection is completely compromised; earth ground is all but disconnected. That wire must route to ground electrodes as directly (straight) as possible, away from other non-grounding wires, no sharp bends, and no splices. it must be the single point earth ground - all four words have electrical significance.

Ground electrodes must also be installed so that all other incoming utility wires (ie cable, telephone, dish, roof antenna) also make a low impedance (ie less than 10 foot) connection to those same electrodes. All this exceeds code requirements for human safety. And is essential for transistor safety.

An AC utility demonstrates good, bad, and ugly (preferred, wrong, and right) solutions:
Tech Tip 08 -Duke Energy
 
  #11  
Old 08-30-15, 06:23 PM
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I will re-consider a QO panel. I priced it out (with breakers) at $270 vs $170 for Homeline. The breakers cost 2x. Biggest difference I see is that QO is copper and Homeline is aluminum.
QO panels come with standard copper bus and are lifetime warranted. Homeline panels are only available with tin plated aluminum bus and have a 10 year warranty. QO breakers are lifetime warranted and Homeline breakers have a 10 year warranty. Homeline is a competitively priced line that Square D brought out in the early '90s because they had lost so much residential marketshare with the QO product. If you are concerned with the price, try looking at the Eaton/Cutler-Hammer CH series panels that also have copper bus and a lifetime warranty. The CH series breakers are also lifetime warranted and now also have the red flag/trip indicator that only QO breakers had for so many years. I think you'll find the CH panel/breaker pricing a little more to your liking than the QO series.

Considering the age of your existing service (at least 30 years old now), I believe I'd replace the meter socket and all service entrance wiring too.
 
  #12  
Old 08-30-15, 07:19 PM
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I'll have a look at the CH series. The $100 price difference between Homeline and QO doesn't bother me at all as long as it's worth it. From comments here, it sounds like it's worth it.

I'm not sure how I'd replace the meter socket since the utility-side in the socket will still be hot. Is there a specific concern with old sockets and service wiring?
 
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Old 08-30-15, 09:36 PM
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Is there a specific concern with old sockets and service wiring?
Not a specific concern but that wiring is outside in the weather.

How does the meter pan look..... clean... not rusted ?
I see conduit coming in to feed the panel.
Is the service going up the house also in conduit.... or is it an underground service ?

You may have to get into the meter pan if the wiring currently coming in from outside isn't long enough.
 
  #14  
Old 08-31-15, 04:42 AM
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From the outside, the meter pan looks ok to me. All wires are in conduit. The conduit from the panel to the meter is entirely within the exterior wall. The meter is fed from underground service.

How would I safely work inside the meter pan?
 
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Old 08-31-15, 07:01 AM
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You can't. The power company would need to do a disconnect of the service lateral at the transformer.
 
  #16  
Old 08-31-15, 07:39 AM
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Ok, I'll ask the power company about disconnecting the power at the transformer.

Now I'm concerned that my service entrance cable might be too short when I try to connect it to my new panel. Am I right to assume that the power would still have to be disconnected at the transformer to replace only the service entrance cable? Or is there a safe way to work in the meter socket with hot wires? (My guess is no.)
 
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Old 08-31-15, 08:04 AM
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Not for someone without live work training, tools and PPE. It's not something you want to try. Youtube arc flash videos for several good reasons why.

The power company shouldn't really have a problem disconnecting at the transformer, although you might want to let them know in advance so they can send the correct technician on the call. The guys who work meters aren't always the same ones who work transformers.
 
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Old 08-31-15, 08:49 AM
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Now I'm concerned that my service entrance cable might be too short when I try to connect it to my new panel.
You do not have service entrance cable, you have individual conductors in conduit. It shouldn't be a big deal at all the replace them with longer conductors after the meter is pulled by someone qualified to work inside a hot meter socket. Without seeing the outside part of the service, my concern is that the existing service entrance wiring and meter socket is already at least 30 years old. Will it last another 30 or more years? I generally would feel better about just replacing it all at the same time.
 
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Old 08-31-15, 08:54 AM
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You can also do a complete new service including mast and meter socket next to the existing panel and service. When the new one is complete then you call the electric company to move the drop. After moving the existing panel can be gutted and used as a junction box to extend existing circuits to the new panel.

This has a couple of advantages. Your not without power while doing the new service so you can relax and take your time. Add a couple of receptacles to the new panel when you set it up and you will have power for essentials after the drop has been moved and your moving the circuits to the new panel.
 
  #20  
Old 08-31-15, 10:41 AM
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A friend sent me a picture of the new Homeline panel his electrician installed 2 years ago. The conductors from the meter enter the panel in a location where I've never seen factory knockouts in any Square-D picture. Am I allowed to drill my own hole in the cabinet to avoid having to install longer conductors from the meter?
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  #21  
Old 08-31-15, 11:32 AM
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You can drill knockout, but need to be aware of minimum bend radius requirements. You will not be able to use the back for a 200 amp service.
 
  #22  
Old 08-31-15, 12:09 PM
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Ok, so are you saying that my friend's panel actually violates code since it's 200 amps?

Do you know where in the code the bend radius requirement is for these service conductors?
 
  #23  
Old 08-31-15, 12:17 PM
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Maybe -- It's article 312.6 The minimum box depth from the end of the fitting to the box edge (cover in this case), in the direction of wire travel, for #4/0 wires is 4" and for #2/0 wires is 3.5". If the installer used #2/0 copper it may be compliant with NEC. If they used #4/0 aluminum it is probably not compliant with NEC, but the inspector may have approved it anyway.

It is also bad practice to wire tie all the conductors like that due to significant heat build up in the center of the bundle. Wires can be loosely grouped in the panel, but should not be tightly bound like structured data cables can be. Depending on how long those conduits are at the top of the panel, and how the cables are fastened on the other side, there could be a significant bundling problem there too.
 
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Old 08-31-15, 12:24 PM
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Great information! I see the table in NEC that you're talking about. But if the conductor enters at the back of the panel, wouldn't table 312.6(B) be the one to use? In that case a #4/0 copper conductor would require 7"! Am I reading that right?
 
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Old 08-31-15, 12:50 PM
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Don't forget that the lugs are closer to the back plane which reduces the bend radius also.
 
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Old 08-31-15, 12:52 PM
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Your friends panel is also missing a bushing on the connector for the service conductors.
 
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Old 08-31-15, 12:54 PM
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All the cables in the two connectors in the center and both sides of the panel are violation too.
 

Last edited by pcboss; 08-31-15 at 07:16 PM.
  #28  
Old 08-31-15, 01:37 PM
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Looking more closely at tables 312.6(A) and 312.6(B), aren't these requirements just saying how far away from the wall of the enclosure the lugs have to be based on wire size? Isn't this a requirement for the panel manufacturer more than the installer?
 
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Old 08-31-15, 06:04 PM
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Snapped some pics of my meter. To my untrained eye, it seems ok. (Looks like there's an old tag sitting on top.) Anybody see something I should be concerned about?

Tried to get the power company to tell me how much they would charge to pull my meter, and they wouldn't tell me. They said it depends on labor and materials and said $200 wouldn't be surprising. Seems really high to me. I've seem them pull my meter half a dozen times in the last year because of wire issues on their side. It took 30 seconds each time! Anybody here in the Oncor service area in Texas have any experience with this?

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  #30  
Old 08-31-15, 06:11 PM
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There should only be a minimal charge to pull the meter. If they had to disconnect at the transformer pad so that you could change the meter pan..... that runs around $275.00 here.
 
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Old 08-31-15, 07:17 PM
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AFAIK, a meter pull is free around my area.
 
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Old 09-01-15, 07:21 AM
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Don't remember which, but the home owner gets one or two free meter pulls per year here.
 
  #33  
Old 09-01-15, 08:31 AM
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Your friends panel is also missing a bushing on the connector for the service conductors.
I thought the same thing at first, but when I looked closer it appears there might be a bonding bushing there on the connector. I believe a grounding locknut with plastic insulating bushing would have been more appropriate.
 
  #34  
Old 09-01-15, 08:31 AM
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Makes a lot of sense to me. Seems short-sighted to make it difficult/costly to have the meter pulled. Just encourages homeowners to break the rules.
 
  #35  
Old 09-03-15, 10:41 AM
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Decided to ask my inspector directly about drilling a hole in the panel for my service entrance conductors. The response I got back wasn't yes or no. I need help from those who have worked with inspectors before. This inspector has been incredibly responsive and helpful so far. I don't get the impression at all that he's out to get me.

Here was his response when I asked about drilling my own hole:
The manufacturer of the panel makes them with specific areas for connections into the panel. Altering entry areas may interfere with the electrical components such as the bus bars, dedicated breaker spaces or grounding. Entering from other than what the manufacturer provides may also hinder proper bending radius of the service entrance conductors.
When I asked for clarification, his response:
I'm saying follow the manufacturer's installation instructions regarding entries into that panel.
Now, the installation instructions don't say anything about drilling my own holes (allowed or not), and I think this is the inspector's way of saying "use common sense." Seems to me as long as I don't drill through a bus bar or something crazy like that, and as long as I comply with NEC 338.24 for service entrance bend radius requirements, I should be ok. Anybody disagree?
 
  #36  
Old 09-03-15, 11:20 AM
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Comercial panel enclosures can be ordered without factory knockouts so entries need to be drilled. As long as you follow bend radius concerns I don't see an issue .
 
  #37  
Old 09-13-15, 12:59 PM
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My 200A entrance runs through 1.5" metallic conduit into the back of the panel. Will a 1.5" insulated grounded bushing comply with code? Or do I need something else?
 
  #38  
Old 09-14-15, 11:17 AM
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My 200A entrance runs through 1.5" metallic conduit into the back of the panel. Will a 1.5" insulated grounded bushing comply with code? Or do I need something else?
1.5" conduit is pretty small for 200 amp service, but you might be able to get 2/0 conductors in it. I don't know without checking the code book.

If the knockouts are concentric with rings remaining, you need a bonding bushing on each end of the metallic conduit. If there are no rings remaining or if the knockout is eccentric (punched the correct size), you would use a grounding locknut. It is possible in some installations to have a bonding bushing on one end and a grounding locknut on the other end.
 
  #39  
Old 09-14-15, 11:52 AM
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Thanks CasualJoe. I need a bonding bushing if the knockouts are concentric because concentric knockouts are electrically compromised? And that's different than eccentric knockouts?

The existing 1.5" conduit definitely looks roomy for the 3 service conductors in my old panel. I'm trying to avoid swapping out either the conduit or the conductors to keep my hand out of the meter socket.

Most likely I'm going to drill my own 2" hole for the 1.5" conduit so it lines up exactly with the hole in my old panel. In that case, I would just need a grounding locknut and plastic bushing, right?
 
  #40  
Old 09-14-15, 12:08 PM
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I'm going to drill my own 2" hole for the 1.5" conduit so it lines up exactly with the hole in my old panel. In that case, I would just need a grounding locknut and plastic bushing, right?
That's right. Most electricians just use a knockout set to punch a quick hole, an eccentric knockout, but it is fine to use a holesaw as well, just takes longer and isn't quite as refined or smooth. Then, use a plastic insulating bushing.
 
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