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Joined: Dec 2001
Posts: 2,498
T
Member
Tonight I googled to find a picture of a US panel in order to explain some things over at some German dicussion board. I stumbled across this pictures, and before I make any statements on it, I wanted to ask you guys if you see any obvious violations.
Panel picture
According to the web site this is a new panel (site is dated 2008) installed in Taunton MA. A few things struck me odd, such as the apparent lack of a GEC and the white wires on those DP breakers top right.

Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
Good eye, TR. Let me explain what I see:

First, I believe this is a 'main' panel, being fed from underground. This is suggested by the type of cable used, the lack of a separate ground buss, and the use of a green bonding screw to bond the case to the neutral buss (visible in lower left).

(Edited to remove a sentence with a big goof! Oops! )

As such, there ought to be a nice, big, fat bare copper wire in there that would connect to a grounding electrode. I see no such wire, though the lug for it is laying in the bottom left of the panel. (That type of lug is designed to attach to the neutral busa).

Generally, the clamps where the cables enter the panel are approved for use with two cables. It appears that this was done.

Looking at the combined neutral/ ground busses, I see several places where more than one wire is landed under a screw. While you are generally allowed as many as three ground wires under one screw, each neutral wire must be mounted separately. In at least on place, there are two white wires under the same screw- an error.

In the far bottom left of the panel is a breaker with some white wires attached to it. This is an AFCI breaker, and the connections are correct.

In the upper right of the panel are several 2-pole breakers with white wires attached. This is wrong; the wires need to be clearly identified as 'hot' wires. This is usually done by marking a significant part of the white wire with colored tape, heat shrink tubing, or colored ink/paint.

The white wires can always be properly marked. How the guy plans to connect to the ground electrode has me puzzled; with the wall closed up, it won't be easy.

============================================
There's another way to look at this panel.

Perhaps there is another another disconnect before this panel. This is very possible, almost certain - as I don't see a meter present either. The grounding electrod conductor might very well be connected at that point.

IF that is the case, there should be FOUR wires entering the bottom of the panel - 2 hots, a neutral, and a ground - and a separate ground buss for the ground wires. The green screw should NOT be used in this arrangement.

Until fairly recently, the part of our code that addresses this situation was a lot more confusine than it is today. With no metal path between the disconnect and the panel - note that the wiring method is a cable, rather than conduit - this is more of a 'technical' violation than a real safety risk.

==========================================

In summary, the guy mixed two different methods in this installation, resulting in something that complies with neither.

Joined: Sep 2002
Posts: 943
Likes: 2
N
Member
I see a main breaker in that HOMEline panel, but do not see a GEC in there & would hope that is not a SE UG feed, I am glad that SE cable is not used here as not a method allowed in the PG&E Greenbook.

Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
You're right ... there is a main breaker ... I was so busy looking at trees I missed the forest! Oops.

Joined: Feb 2003
Posts: 939
F
Member
There are couple quirks I will say in here the netural conductors that bundled in each hole that is a no-no but for EGC c'est ok IMO it will be alot nicer if it have own grounding bussbar for this useage which I done all the time it cost little more upfront but in long run it look much neater plus what more .,,

If that area requied a extreal disconnection source it is very easy to swap over to 4 conductor set up.

Merci.
Marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Joined: Aug 2007
Posts: 853
L
Member
As A Massachusetts guy-

Doubled up neutrals- very wrong.
As far as GEC- Based on bonding screw- lower left corner.
(1) Perhaps it is plastic water pipe (main)= no connection.There fore no visible GEC in panel.
-Unless done all in 'PEX' I'm concerned about no bonding conductor to what little copper pipe there may be.-
(2) 2 ground rods- connected at the meter socket (not uncommon here).
(3) Uffer extended outside,same as above.

As far as the SE cable, very common here as well.
I can't see enough below the panel to comment on UG or not.

Basically,looks OK.

Joined: Dec 2001
Posts: 2,498
T
Member
I already thought the bottom left ought to be a GFCI/AFCI breaker based on the curled white wire. However, the top right ones are (even to my outside view) clearly double poles, so I expected re-identified whites as Reno pointed out.

@leland: so you don't run a ground between meter and main panel then, only the neutral which is bonded to the enclosure at the main panel?

Joined: Aug 2007
Posts: 853
L
Member
Originally Posted by Texas_Ranger
I already thought the bottom left ought to be a GFCI/AFCI breaker based on the curled white wire. However, the top right ones are (even to my outside view) clearly double poles, so I expected re-identified whites as Reno pointed out.

@leland: so you don't run a ground between meter and main panel then, only the neutral which is bonded [color:#CC33CC]to the enclosure at the main panel?
[/color][/color]

That is correct,here. Bond at the meter OR the panel,Again,Concern about no visual bond to water Piping.
As far as 're-Identification', on the residential end,Very rarely to never.

This panel may just be a "change out",Therefore not requiring the AFCI,(it does look like 'very'new wires though) Bottom left is most likely the GFCI feeding the bathrooms,garage and outside receps.

Joined: Aug 2007
Posts: 853
L
Member
Above comments based on 'assumption',That this is the MAIN panel.
Drop to meter,then to main breaker.

Joined: Mar 2008
Posts: 144
Member
in Taunton Ma eh? i may have to go hunt this one down, its in the town just next to me. ill remember to take pics if i can find it wink


-Joe
“then we'll glue em' then screw em'”
-Tom Silva
TOH
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