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Re: Undersized Meter Base

Bubba, you have a standard 200A 120/240V meterbase. It appears to be in good shape but lacks an intersystem ground, which is a recent Code requirement. This gives the phone, cable and sat. companies something to tie their grounds to and only cost about $20.

Panels A & B don’t seem to have any major problems and A has about 8 empty spaces. But, I tried to zoom in better and all I got was pixals.

The following is out of the 2011 NEC:
Beginning with the 2008 Code, the terms lighting and appliance branch-circuit panelboards and power panelboardsare no longer used. In addition, the requirement for a maximum of 42 overcurrent devices was also removed (see 408.54) and now applies only with Exception No. 2 of 408.36.
Exception No. 2: Individual protection shall not be required for a panelboard protected on its supply side by two main circuit breakers or two sets of fuses having a combined rating not greater than that of the panelboard. A panelboard constructed or wired under this exception shall not contain more than 42 overcurrent devices. For the purposes of determining the maximum of 42 overcurrent devices, a 2-pole or a 3-pole circuit breaker shall be considered as two or three overcurrent devices, respectively.
408.54 Maximum Number of Overcurrent Devices. See related UL
A panelboard shall be provided with physical means to prevent the installation of more overcurrent devices than that number for which the panelboard was designed, rated, and listed.
For the purposes of this section, a 2-pole circuit breaker or fusible switch shall be considered two overcurrent devices; a 3-pole circuit breaker or fusible switch shall be considered three overcurrent devices.
Section 408.54 limits the number of overcurrent devices to the quantity for which it was designed, rated, and listed. See Exception No. 2 to 408.36 for restrictions on the number. See also the commentary following 408.30.

So, the number of breakers in each panel has not been been exceeded but only a load calculation will tell if a particular circuit has more load than is allowed.

True, you may have everything running at the same time but the stuff you mentioned shouldn’t be a huge problem.

That said, I believe you will find all your circuits are very lightly loaded, which is a super safe condition, just the opposite of what the inspector was talking about.

No permit is required to examine and “pretty up” the wiring by an electrician. He/she will also ask you to turn everything on and verify loading is acceptable. Something you can do yourself would be to make a new directory of what each breaker controls, to reduce the electricians time.

Have the electrician come with an intersystem ground for outside and drive a second ground rod (also a new requirement). You can verify the breakers are all the same manufacturer as the panels. If different, record the sizes he/she will need to bring.

Re: Undersized Meter Base

Thank you The Semi-Retired Electric, that's very helpful I will make sure to resolve the grounding issue with an electrician.

Here are a few more pictures with the panel and breakers zoomed in.

I am not sure if that helps any.

Now, since these breakers are not full size ones, they are "half height" ones does this make a difference? Does it mean panel B being full they have overloaded what is normally safe?

Re: Undersized Meter Base

Thanks for posting pictures. The problem as I see it is that you have a single 200A meter base, feeding two 200A panels.... in other words, the incoming power lines and meter base may need to be upgraded to 400A (or maybe 320A; I'm don't know what code dictates).

That is, with a 200A main breaker in each panel, there is potential to pull up to 400A through the meter if everything in the house is turned on and going full-bore. Unlikely event, but I think what your inspector was getting at was that the load could exceed 200A which is the rated limit of the meter, meter base, and incoming wiring.

Re: Undersized Meter Base

Thank you. I will ask the electrician about whether I need two meters.

While we are on this subject I have a few other curious questions. In the metal box in the middle where the line comes in and splits to enter the right and left panels. What is the name of this box? Is this part of the panel?

Inside this box I can see the lines wrapped in black and white tapes into two bundles. Is this legit?

Also in examining the panel I noticed all the white (neutral) wires are tied to this vertical bar.

Zoom in:

Do you see two green wires also tied to it? Is this normal? Looks strange to me. I wonder if this is meant to be a neutral white wire but they ran out of white so decided to use green? I traced it to the other end of the conduit and where it came out it's being used as a ground - in other words it spliced into a pigtail. Now this house is all EMT and metal boxes so really it doesn't need to have green conductors except in individual boxes right? Or may be this is a legit usage and I am just confused.

Re: Undersized Meter Base

What fencepost said.

It's hard to tell what size wire is feeding the trough in the middle or if the taps are properly made up.

There are exceptions but generally a breaker protects the panel and wire. The meter is protected by what size the downstream breaker is.

Your loads may be so small that you could replace the main breakers in each panel with 100A units, if forced to do so.

Only an on-site inspection will determine what needs to be done.

Re: Undersized Meter Base


Any comments on the green wire question?

Is there any reason to run a green wire attached to the neutral bar at the panel across a run of 75' rigid conduit to a metal box and in the metal box it's attached to the box with the green ground screw?

I have traced the run and it's all conduit, nothing in between. In fact the entire house is of conduits (a mix of rigid and EMT) and metal boxes only in the ceiling sometimes a junction box may spread out to a few recessed lights with MC cables.

Re: Undersized Meter Base

The green and the white wires should be on the same bus in that panel.

The green wire is called the equipment grounding conductor and so is a properly made up metal conduit.

In some jurisdictions the green wire is not required. But, if all the connections in a metal raceway are not tight you may not have electrical continuity between boxes (un-grounded boxes), so some places required both.

Re: Undersized Meter Base
bubba wrote:

Any comments on the green wire question?

To expand on what Semi-Retired Electric said, it is normal for the ground and neutral to share a common bus in the panel containing the service disconnect (commonly called the "service entrance"). Each of these panels is a service entrance.

(If there are any panels "downstream" of these, they are sub-panels and not the service entrance, and therefore require the ground and neutral to be isolated on separate buses. There should be separate ground and neutral wires running from the service entrance panel to the sub panel. Typically the ground busbar would not be connected to a separate ground rod, although it may be required if in a separate building. Someone more knowledgeable of the codes could comment on this.)

Take note of the green screw just below the green ground wire. It bonds the metal cabinet to the busbar. In a subpanel, this bonding would only be to the grounding busbar.

Re: Undersized Meter Base

Bubba, just a few extra comments:

Only one meter is allowed per customer/building. So, if you need more than 200A, which I doubt, you will need a bigger meter box and larger wire to the middle panel.

As it is now you could "demand" more power through the meter than it's rated for. And, if the wire from the meter is the same size as the wire going to each 200A breaker it could overheat.

Only an electrician can properly sort this out, as the inspector stated.

Re: Undersized Meter Base

Most electric utilities will send someone out to confirm your service feed size for free, and usually being nice guys, most of them will also be glad to look at (but not touch) the feed to your panel as well. They can tell you if the meter-to-panel wiring is OK so you'll know if you need more work there. While they are there, ask them if your licensed electrician is permitted to change out the meter base alone or if they have to cut the current to it from the supply- that can vary by utility company rules and may need to be scheduled some days ahead of time. If the service feed isn't rated for 400A you'd do better to see if you reduce the panel's loads to 200A total as the utility company will often want a big chunk of change to upgrade a service when it's underground!



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