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    230.71(A), 90.4, and a MLO panel

    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
    Last edited by dnem; 08-15-06, 10:05 PM.
    David
    I get paid for doing stuff in Ohio

    #2
    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

    Comment


      #3
      Originally posted by bjp_ne_elec
      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
      David
      I get paid for doing stuff in Ohio

      Comment


        #4
        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
        Don, Illinois
        (All code citations are 2017 unless otherwise noted)

        Comment


          #5
          Originally posted by don_resqcapt19
          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:
          Master Electrician
          Electrical Contractor
          Richmond, VA

          Comment


            #6
            Originally posted by don_resqcapt19
            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:

            Originally posted by dnem
            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


            Originally posted by dnem
            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


            Originally posted by dnem
            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

            Originally posted by dnem
            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
            David
            I get paid for doing stuff in Ohio

            Comment


              #7
              Originally posted by don_resqcapt19
              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.
              Rob

              Moderator

              All responses based on the 2017 NEC unless otherwise noted

              Comment


                #8
                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?



                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?
                Last edited by iwire; 08-16-06, 05:31 AM.

                Comment


                  #9
                  [COLOR=black]
                  Originally posted by dnem
                  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 ?
                  [/COLOR]
                  [COLOR=black]All that is there are six then it is code compliant even if it were a 42 circuit panel[/COLOR]

                  [COLOR=black]
                  Originally posted by dnem
                  2] Do you believe that 230.71(A) can be used to prevent a push-in MLO with more than 6 possible breaker slots ?
                  [/COLOR]
                  [COLOR=black]On what basis would you turn one down[/COLOR]

                  [COLOR=black]
                  Originally posted by dnem
                  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 ?
                  [/COLOR]
                  [COLOR=black]This would be a code compliant installation[/COLOR]

                  [COLOR=black]
                  Originally posted by dnem
                  4] Do you think failing a push-in MLO with more than 6 breaker slots is a correct use of 90.4 ?
                  Originally posted by dnem
                  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.
                  [/COLOR]
                  Originally posted by dnem

                  [COLOR=black]I failed the service main inspection for 230.71(A), max 6 disconnects.[/COLOR]
                  I beg to differ with you here my friend. You did not do an inspection on this house, what you did was an expection.
                  Mike Whitt
                  [COLOR=#000066]God answers Knee-Mail. [/COLOR]

                  Comment


                    #10
                    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.

                    Comment


                      #11
                      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

                      Comment


                        #12
                        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).
                        Just because you can, doesn't mean you should.

                        Comment


                          #13
                          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.
                          Master Electrician
                          Electrical Contractor
                          Richmond, VA

                          Comment


                            #14
                            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.
                            Mark
                            Kent, WA

                            Comment


                              #15
                              Originally posted by iwire
                              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?



                              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

                              Originally posted by iwire
                              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.

                              Originally posted by iwire
                              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 ?

                              Originally posted by iwire
                              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.

                              Originally posted by iwire
                              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?



                              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
                              Last edited by dnem; 08-16-06, 11:57 PM.
                              David
                              I get paid for doing stuff in Ohio

                              Comment

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