230.71(A), 90.4, and a MLO panel

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dnem

Senior Member
Location
Ohio
First I want to acknowledge that at least half of you contractors that clicked on this thread, did so because you saw 90.4 and you're grumbling under your breathe right now like Dastardlys dog, Muttley from Wacky Racers.

I'm not bringing up 90.4 because of the "interpretations of the rules" phrase, I'm looking at the "for deciding on the approval of equipment and materials".

I inspected a house where the EL contractor put in a Siemens MLO panel for the main. It has two sideways mounted 200amp breakers in their own sections, similiar to what you might commonly find in a commercial MDP. Under that is a single section with KOs for 12 push-in breakers. This section is not feed by either of the upper 200s. It has a MLO capacity for the two 200 doublepoles plus 12 singles, 6 doublepoles, or a combination.

I failed the service main inspection for 230.71(A), max 6 disconnects.

I was forwarded an email that was from one Siemens employee to another that made the claim that the panel did not violate 230.71(A) in installations that did not have more than 6 breakers in the panel at the time of the inspection and the email also claimed that the panel is rated as service equipment. The email made the claim that inspectors that turn down that installation are not applying 230.71(A) correctly.

So my questions are:
1] Do you think there is a difference between using this size residential MLO as a main and using a more than 6 breaker section commercial MLO MDP, if both have only 6 breakers at the time of service main inspection ?
2] Do you believe that 230.71(A) can be used to prevent a push-in MLO with more than 6 possible breaker slots ?
3] Now taking it one step further. Do you think a 42 space push-in breaker type MLO should be accepted for a main if only 6 breakers are in at the time of inspection and there's no issue with wire sizes ?
4] Do you think failing a push-in MLO with more than 6 breaker slots is a correct use of 90.4 ?

David
 
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bjp_ne_elec

Senior Member
Location
Southern NH
In my opinion, I would have an issue with this installation, and if someone wanted - for what ever reason to use an MLO - then put in a disconnect. Even if the panel had six (6) breakers at inspection, what do you thinks going to happen down the road. Obviously, once the seventh breaker did ever get installed - the installation should not pass inspection - but I guess my point it, why would anyone even want to set something like this up?

Brett
 

dnem

Senior Member
Location
Ohio
bjp_ne_elec said:
but I guess my point it, why would anyone even want to set something like this up?

The EL contractor wanted a main panel that could feed 2 different 200amp subs and 2 AC units. He says that Seimens told him that the SE rated panel that they sent him is their only option. It has the 2 sections with each containing a 200amp breaker feed off the main buses and a third section with 12 KOs also feed directly off the main buses. They claim that they have nothing of a smaller capacity and send this same gear out everywhere to be installed in situations where 2 200s plus at least one other breaker is desired.

The one Seimens employee that I've spoken to so far gave me the same story.

I don't question the EL contractors intent to feed the 2 200amp subs and the 2 ACs only. I question having a MLO push-in breaker panel in a house that allows the HO to push-in breakers "at will" without having to install more panels and tap the SE conductors to feed the new panels.

David
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
You can only inspect what has been installed, not what may be installed in the future. If the panel is service rated, and has 6 or less breakers installed, there is no code violation. A red tag here would be like a cop giving you a speeding ticket just because you could make the car go faster than the permitted speed limit.
Don
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
don_resqcapt19 said:
A red tag here would be like a cop giving you a speeding ticket just because you could make the car go faster than the permitted speed limit.
Conspiracy to commit speeding? :confused:
 

dnem

Senior Member
Location
Ohio
don_resqcapt19 said:
You can only inspect what has been installed, not what may be installed in the future. If the panel is service rated, and has 6 or less breakers installed, there is no code violation. A red tag here would be like a cop giving you a speeding ticket just because you could make the car go faster than the permitted speed limit.
Don

Let me make sure that I understand your position correctly since you didn't answer any of my questions.

I'm concluding that you would answer my questions this way:

dnem said:
1] Do you think there is a difference between using this size residential MLO as a main and using a more than 6 breaker section commercial MLO MDP, if both have only 6 breakers at the time of service main inspection ?

No


dnem said:
2] Do you believe that 230.71(A) can be used to prevent a push-in MLO with more than 6 possible breaker slots ?

No


dnem said:
3] Now taking it one step further. Do you think a 42 space push-in breaker type MLO should be accepted for a main if only 6 breakers are in at the time of inspection and there's no issue with wire sizes ?

Yes

dnem said:
4] Do you think failing a push-in MLO with more than 6 breaker slots is a correct use of 90.4 ?

No

Are these your answers ?

David
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
don_resqcapt19 said:
You can only inspect what has been installed, not what may be installed in the future. If the panel is service rated, and has 6 or less breakers installed, there is no code violation. A red tag here would be like a cop giving you a speeding ticket just because you could make the car go faster than the permitted speed limit.
Don

I agree. Look at the installation in front of you and determine if a violation is present. Forget about what might happen tomorrow.
 

iwire

Moderator
Staff member
Location
Massachusetts
David, Don's answer was very clear.

IMO you are trying to complicate an easy question in order to justify your red tag.

You can not inspect for what may happen.

The NEC does not limit the number of spaces the NEC limits the number of disconnects.

If you where inspecting the panel that this label was on would you ignore the labeling if the panel has more than 6 spaces?

408-14.jpg


If someone was to use a 200 amp fused disconect to supply a 125 amp load would you fail the job because someone could over fuse it later?
 
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jwelectric

Senior Member
Location
North Carolina
dnem said:
1] Do you think there is a difference between using this size residential MLO as a main and using a more than 6 breaker section commercial MLO MDP, if both have only 6 breakers at the time of service main inspection ?
All that is there are six then it is code compliant even if it were a 42 circuit panel

dnem said:
2] Do you believe that 230.71(A) can be used to prevent a push-in MLO with more than 6 possible breaker slots ?
On what basis would you turn one down

dnem said:
3] Now taking it one step further. Do you think a 42 space push-in breaker type MLO should be accepted for a main if only 6 breakers are in at the time of inspection and there's no issue with wire sizes ?
This would be a code compliant installation

dnem said:
4] Do you think failing a push-in MLO with more than 6 breaker slots is a correct use of 90.4 ?
When an inspector quotes 90.4 on an inspection of mine I just throw it in the trash and proceed with the job. If he can?t find a section of the code to quote it does not make him a governmental body with the power to make up a rule.

dnem said:
I inspected a house where the EL contractor put in a Siemens MLO panel for the main. It has two sideways mounted 200amp breakers in their own sections, similiar to what you might commonly find in a commercial MDP. Under that is a single section with KOs for 12 push-in breakers. This section is not feed by either of the upper 200s. It has a MLO capacity for the two 200 doublepoles plus 12 singles, 6 doublepoles, or a combination.
dnem said:
I failed the service main inspection for 230.71(A), max 6 disconnects.
I beg to differ with you here my friend. You did not do an inspection on this house, what you did was an expection.
 

iwire

Moderator
Staff member
Location
Massachusetts
jwelectric said:
When an inspector quotes 90.4 on an inspection of mine I just throw it in the trash and proceed with the job. If he can?t find a section of the code to quote it does not make him a governmental body with the power to make up a rule.

Mike that is an excellent point, I am really glad you brought this up.:)

In my experience inspectors are not actually the AHJs although they either believe or want us to believe that they are AHJs.

In my area they are called out in the state laws as "Inspector of wires".

The State is the AHJ.
 

andrew

Member
Location
Florida
Square D makes basically the same type equipment you are referring to. There is a 4/8 MLO which actually comes off of the buss which feeds both the 2 main bkrs. The difference being there is a mfg note which states "2-pole bkrs only". If someone has a single pole bkr in it I turn them down per 110.3B.
In your case David I would like to agree with you but I cannot. We are inspectors not expectors like Mike says. Note lines that is your answer. Protect yourself that way. What do you think they do with those pool alarms after you've ispected them?

Have a great day,
Andrew
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
This discussion is on a "split-bus" panel (examples can be seen in the NEC Handbook exhibits 408.3 and 408.4). While these may be correctly installed under 230.71, when used for residential services they are often mis-applied under 408.34 and 408.36(A).
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I also thought of the split-bus panels we've seen used in the past. The top section will accept 12 1-pole breakers, although 6 2-pole breakers are the acceptable limit.
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
I'm wondering how large this service is. I hope it was at least 400A, otherwise it was an expensive solution. I agree you can only inspect what is there, but I would also encourage a label on the unused breaker slots that can't ever be used (the bottom 4 slots) and perhaps indicate "breakers must be > 30A or have no neutral loads" in the remaining 4 slots.
 

dnem

Senior Member
Location
Ohio
iwire said:
David, Don's answer was very clear.

IMO you are trying to complicate an easy question in order to justify your red tag.

You can not inspect for what may happen.

The NEC does not limit the number of spaces the NEC limits the number of disconnects.

If you where inspecting the panel that this label was on would you ignore the labeling if the panel has more than 6 spaces?

408-14.jpg


If someone was to use a 200 amp fused disconect to supply a 125 amp load would you fail the job because someone could over fuse it later?

There are a number of problems with your post

iwire said:
David, Don's answer was very clear.

No it wasn't. If he had answered the questions then it would be clear or at least more clear than it was.

iwire said:
IMO you are trying to complicate an easy question in order to justify your red tag.

And what is the justification for not answering a simple question ? Is your position unable to withstand examination ? Are you saying that the answer for a 12 slot MLO is different than the answer for a 42 slot MLO ? Why does follow up questions "complicate an easy question" ? Does the logic that you're using to come to one answer break down if you are asked follow up questions ?

iwire said:
You can not inspect for what may happen.

I've heard this concept stated many times on this site, but I've never seen it supported. What is the purpose of a second small appliance circuit on the kitchen counter [210.52(B)(3)] ? Is the code panel providing for a “what may happen” or do they know the load in every kitchen in every house in the entire country beforehand ?

What is “special permission” based on ? Is the intent of 230.2(C)(3) for the AHJ to grant special permission without looking at the possible repercussions of the exemption from a requirement ? And what is the purpose of planning for settlement that might never happen [300.5(J)] ? The code is filled with “what ifs”. A good portion of the code is based on “what ifs”.

I know that all hell would break loose if every AHJ would “what if” every single installation to death. But the opposite, which is to ignore all repercussions of a specific installation, is no less of a dysfunctional outcome. A balance has to be found between letting the inspector do anything he wants and tieing his hands and not letting him do anything except a mechanical recitation of the code.

iwire said:
The NEC does not limit the number of spaces the NEC limits the number of disconnects.

If you where inspecting the panel that this label was on would you ignore the labeling if the panel has more than 6 spaces?

408-14.jpg


If someone was to use a 200 amp fused disconect to supply a 125 amp load would you fail the job because someone could over fuse it later?

This is the only section of your response that actually attempts to address the issue rather than just perpetuating the bias that most contractors on this site show toward issues that involve inspectors. Your question about your example label and your last question about the fuses are very good ones. Ones that I will have to ponder because they are applicable, unlike many other responses by various posters that rely on emotion rather than logical development of concepts.

David
 
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dnem

Senior Member
Location
Ohio
jwelectric said:
When an inspector quotes 90.4 on an inspection of mine I just throw it in the trash and proceed with the job. If he can?t find a section of the code to quote it does not make him a governmental body with the power to make up a rule.

And in Medina County Ohio all that would get you was a house that the power company would refuse to energize. You wouldn't get a meter without a passing inspection.

Now rather than acting like a child would you rather have an intelligent adult discussion ?

David
 

dnem

Senior Member
Location
Ohio
iwire said:
jwelectric said:
When an inspector quotes 90.4 on an inspection of mine I just throw it in the trash and proceed with the job. If he can’t find a section of the code to quote it does not make him a governmental body with the power to make up a rule.

Mike that is an excellent point, I am really glad you brought this up.:)

In my experience inspectors are not actually the AHJs although they either believe or want us to believe that they are AHJs.

iwire said:
The State is the AHJ.

Whoever the AHJ is where you live, you're not going to get power or an occupancy permit without passing inspection. If you wish to take any particular issue to a higher source than the inspector, go right ahead, but the inspectors finding will be the starting point of any hearing and the inspector will be able to state the reason for his finding. If you can't present a well thought out reason to the appellate body, they will not overturn the inspectors finding.

Statements like, “I tore up the inspectors writeup because he cited 90.4” will not bring you the outcome that you’re looking for. Showing contempt for the position of the inspector does not improve your argument [or lack thereof] with the appellate body.

So before you congratulate each other on your various abilities to sling put downs toward the inspector, you should put some effort into creating a logical argument. During that process you might realize that the inspector is often not the idiot that you assume, and most of us actually have the welfare of the occupant/owner in mind ........ which isn’t such a bad starting point to come from.

David
 
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dnem

Senior Member
Location
Ohio
jim dungar said:
This discussion is on a "split-bus" panel (examples can be seen in the NEC Handbook exhibits 408.3 and 408.4). While these may be correctly installed under 230.71, when used for residential services they are often mis-applied under 408.34 and 408.36(A).

This is not a split bus panel, it is a MLO

A split bus panel will have more than one set of buses and a breaker attached to one set of buses will feed/protect the other set of buses. The MLO has every breaker attached directly to one single set of buses. Each breaker in the entire panel is independent of all other breakers.

David
 

dnem

Senior Member
Location
Ohio
Before anyone else posts on this thread, please note that the very fact that I chose to post this situation shows that I am interested in more information and opinions. The questions that I have asked are what I am continuing to debate in my mind.

If you're looking for an a-hole inspector or a stand-in to abuse instead of confronting your own local inspector that you are upset with, please look elsewhere. I am not interested in providing anger therapy for anyone.

For those of you that have answered with thoughtout replies, I thank you for taking time to respond. I have read every word everyone of you has posted and will reply as much as time will allow me to.

David
 
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