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    Ufer ground

    Is a ufer ground required if a foundation or footing is to be used installed? We are putting a generator on a foundation. The foundation has rebar. IS the rebar required to be bonded as part of the grounding electrode system ? Please provide the address in NEC if yes and or no.

    #2
    Is it just a slab or does it have a footing? Rebar in a slab does not qualify as a CEE so it wouldn't need to be used.
    Rob

    Moderator

    All responses based on the 2017 NEC unless otherwise noted

    Comment


      #3
      Originally posted by infinity View Post
      Is it just a slab or does it have a footing? Rebar in a slab does not qualify as a CEE so it wouldn't need to be used.

      Its a 15' x 10' slab with a 2' footing around the sides. So yes it has a footing. is this required by NEC to be part of ground?
      Last edited by GoldDigger; 05-24-18, 08:17 PM. Reason: Fix QUOTE

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        #4
        Originally posted by infinity View Post
        Is it just a slab or does it have a footing? Rebar in a slab does not qualify as a CEE so it wouldn't need to be used.
        My understanding is that if there's 20 linear ft of rebar somehow connected together then it qualifies as a CEE and per 250.50 it must be bonded to the grounding electrode system. Maybe you can educate me as to why a slab would be different.

        Comment


          #5
          The NEC is a little fuzzy on this one, IMO it is not required to be connected because you are not touching the service. If the building already has a CEE then the code is clear it is not required to be connected.
          Rob

          Moderator

          All responses based on the 2017 NEC unless otherwise noted

          Comment


            #6
            Originally posted by infinity View Post
            The NEC is a little fuzzy on this one, IMO it is not required to be connected because you are not touching the service. If the building already has a CEE then the code is clear it is not required to be connected.
            It is quite unfortunate that it is so unclear, because it gives AHJs the ammunition to require it for all new foundation work.

            Comment


              #7
              Some generators require an electrode so that ufer would be great for it.
              They say I shot a man named Gray and took his wife to Italy
              She inherited a million bucks and when she died it came to me
              I can't help it if I'm lucky

              Comment


                #8
                Originally posted by Dennis Alwon View Post
                Some generators require an electrode so that ufer would be great for it.
                Would that require you to connect it to the building GES too?

                Originally posted by MRKN View Post
                It is quite unfortunate that it is so unclear, because it gives AHJs the ammunition to require it for all new foundation work.
                The NEC wording says that all qualifying electrodes present must be used so that makes it a somewhat gray area. Like I said if you already have a CEE then you are not required to connect other CEE's that are added in the future.
                Rob

                Moderator

                All responses based on the 2017 NEC unless otherwise noted

                Comment


                  #9
                  Originally posted by infinity View Post
                  The NEC is a little fuzzy on this one, IMO it is not required to be connected because you are not touching the service. If the building already has a CEE then the code is clear it is not required to be connected.

                  The service is a meter bank about 50' away. we are installing a slab/foundation for a skid. I know I mentioned generator but I am clear not its all inclusive. The telco, panel, and generator all sit on skid. The new skid will tie into existing ground ring. I am concerned that the slab the guys already poured needed to have ufer and or if its even needed since it has steel.

                  Comment


                    #10
                    Originally posted by MBLES View Post
                    The service is a meter bank about 50' away. we are installing a slab/foundation for a skid. I know I mentioned generator but I am clear not its all inclusive. The telco, panel, and generator all sit on skid. The new skid will tie into existing ground ring. I am concerned that the slab the guys already poured needed to have ufer and or if its even needed since it has steel.
                    If it's already poured and the AHJ didn't hold them up from pouring you're good to go under 250.50 "that are present". Welp, guess it's no longer present now.

                    Comment


                      #11
                      Originally posted by MRKN View Post
                      My understanding is that if there's 20 linear ft of rebar somehow connected together then it qualifies as a CEE and per 250.50 it must be bonded to the grounding electrode system. Maybe you can educate me as to why a slab would be different.
                      only if it is in the footing.

                      250.52 Grounding Electrodes
                      ...
                      (3) Concrete-Encased Electrode. A concrete-encased electrode
                      shall consist of at least 6.0 m (20 ft) of either (1) or (2):

                      (1) One or more bare or zinc galvanized or other electrically
                      conductive coated steel reinforcing bars or rods of not
                      less than 13 mm (1∕2 in.) in diameter, installed in one
                      continuous 6.0 m (20 ft) length, or if in multiple pieces
                      connected together by the usual steel tie wires, exothermic
                      welding, welding, or other effective means to create a
                      6.0 m (20 ft) or greater length; or
                      (2) Bare copper conductor not smaller than 4 AWG

                      [COLOR="#FF0000"]Metallic components [/COLOR]shall be encased by at least 50 mm
                      (2 in.) of concrete and shall be located horizontally within that
                      portion of a concrete foundation or footing that is in direct
                      contact with the earth or [COLOR="#FF0000"]within vertical foundations or structural
                      components or members that are in direct contact with
                      the earth.[/COLOR] If multiple concrete-encased electrodes are present
                      at a building or structure, it shall be permissible to bond only
                      one into the grounding electrode system.

                      Informational Note: Concrete installed with insulation, vapor
                      barriers, films or similar items separating the concrete from the
                      earth is not considered to be in “direct contact” with the earth.
                      Bob

                      Comment


                        #12
                        Originally posted by infinity View Post
                        Would that require you to connect it to the building GES too?



                        The NEC wording says that all qualifying electrodes present must be used so that makes it a somewhat gray area. Like I said if you already have a CEE then you are not required to connect other CEE's that are added in the future.

                        I take 250.50 to mean if all the electrodes are present you would bond together. Where does steel or rebar in a foundation required to be grounded. 250.50a3 says encased electrode not encased rebar. I guess this is where it vague.

                        Comment


                          #13
                          Originally posted by infinity View Post
                          The NEC is a little fuzzy on this one, IMO it is not required to be connected because you are not touching the service. If the building already has a CEE then the code is clear it is not required to be connected.
                          This is what it says.

                          If multiple concrete-encased electrodes are present
                          at a building or structure, it shall be permissible to bond only
                          one into the grounding electrode system.
                          This is a different structure so the CEE from the other building would not have to be bonded anyway. having said that, the EGC coming from the other structure to the new skid would effectively bond tha new skid and whatever GES it has to the existing structures GES.
                          Bob

                          Comment


                            #14
                            Originally posted by MBLES View Post
                            I take 250.50 to mean if all the electrodes are present you would bond together. Where does steel or rebar in a foundation required to be grounded. 250.50a3 says encased electrode not encased rebar. I guess this is where it vague.
                            One or more bare or zinc galvanized or other electrically
                            conductive coated steel reinforcing bars or rods
                            The steel that is encased in the concrete would be the rebar mentioned in the code.

                            250.50 says all the GE at a structure have to be bonded together. however you are dealing with a separate structure here. The new skid CEE is not associated with the existing structure.
                            Bob

                            Comment


                              #15
                              [QUOTE=petersonra;1918105]The steel that is encased in the concrete would be the rebar mentioned in the code.

                              250.50 says all the GE at a structure have to be bonded together. however you are dealing with a separate structure here. The new skid CEE is not associated with the existing structure.[/QUOT

                              In Your opinion I wouldnt need the ufer ground isnt needed? Im not trying to get away with anything. I am trying to understand the why i would need a ufer in the first place. I know of plenty of places where this was never an issue.
                              Last edited by MBLES; 05-24-18, 06:45 PM.

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