conduit

  • What are the differences between electrical metallic tubing (EMT)?

    What are the differences between electrical metallic tubing (EMT)?

    Electrical Metallic Tubing (EMT) is Listed to Standard for Electrical Metallic Tubing – Steel, UL 797 and produced to American National Standards Institute – ANSI C80.3 WW-C-581 Class 2 Type A with Standard for Electrical Intermediate Metal Conduit -Steel, UL 1242

  • Can EMT be direct-buried?

    Can EMT be direct-buried?

    The 2005 National Electrical Code (NEC) allows the direct burial of all three products as noted in their respective Articles: RSC Section 344.10 (B) Corrosion Environments. “RMC, elbows, couplings, and fittings shall be permitted to be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences where protected by corrosion protection and judged suitable for the condition.” IMC Section 342.10 (B) Corrosion Environments. “IMC, elbows, [.....]

  • What Standards apply to steel conduit/tubing?

    What Standards apply to steel conduit/tubing?

    If the presence of water is a problem, one of the following steps may help: 1. Install a typical Quazite(TM) concrete-polymer underground open bottom junction box over a gravel sump. This can be done by excavating a hole approximately 3′ X 3; filling it with 1 to 2 inch gravel and placing the Quazite(TM) box flush with the ground prior to entering the building, or at the lowest location in [.....]

  • Can IMC and EMT be installed in concrete?

    Can IMC and EMT be installed in concrete?

    The National Electrical Code (NEC) allows all three products to be installed in concrete, as noted in their respective Articles: (Also see NEC 300.6(A)(3). IMC Section 342.10 (B) Corrosion Environments. “IMC, elbows, couplings, and fittings shall be permitted to be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences where protected by corrosion protection and judged suitable for the condition.” EMT Section 358.10 (B) Corrosion [.....]

  • Do EMT comply with the requirements of NFPA ?

    Do EMT comply with the requirements of NFPA ?

    Members of the Conduit Committee of the Steel Tube Institute apply a zinc coating to galvanize steel RMC, IMC and EMT. Therefore, these products are “protected by corrosion protection” as the Code requires. However, in severe corrosive environments, the designer or AHJ may decide to require additional or supplementary protection. If supplementary corrosion protection is required or desired, it can be provided by a factory-applied PVC coating, paint approved for [.....]

  • What is the coefficient of expansion for steel conduit/EMT/IMC and why is this significant?

    What is the coefficient of expansion for steel conduit/EMT/IMC and why is this significant?

    The coefficient of expansion for steel conduit/EMT is 6.5×10-6 in./in./°F. This is significant as it relates to whether or not expansion fittings would be required in a particular application. Expansion fittings are installed where significant temperature differentials are anticipated The Table also shows the length changes for steel conduit at each temperature differential. This will help determine the need for expansion fittings. For information about the use of expansion fittings, [.....]