Common use of Wiring and Conduit Clause in Contracts

Wiring and Conduit. a. All system wiring shall be of an MEC approved wiring method. All conductors shall have a temperature rating of 90 degrees C or lower. b. All conductors shall be copper, sized appropriately to minimize line losses. c. All conduits used in interior building applications shall be electro metallic tubing (“EMT”). d. All exterior conduits shall be hot dipped galvanized EMT with weather tight compression fittings and expansion joints as required. e. Expansion fittings shall be used in conduit runs in compliance with MEC article 300.7. A value of 144°F (80°C) shall be used for the maximum change in temperature (delta T) in the calculation of conduit expansion. f. All conduits shall be bonded at each end using listed bonding bushings. g. Where conduit is attached to roofs, fully flashed, non ferrous stanchions shall allow for expansion and contraction. For roof-mounted conditions, conduits shall be supported at a height greater than 3.5 inches by fully flashed, non ferrous stanchions. Manufacturer’s approved surface applied stanchions shall be used on membrane roofs. h. All outdoor electrical enclosures shall be NEMA 3R and have watertight connections. i. Exposed cables shall be listed as sunlight resistant and have a temperature rating of 90°C. These conductors shall be properly secured and well supported. Conductors are not permitted to be resting on the abrasive surfaces such as asphalt shingles. j. All wiring and conductors installed in subsurface applications shall be housed in utility grade PVC conduit(s) sufficiently covered and include trench warning identification. Spare conduits shall also be installed with a volumetric capacity of at least 25% of the original service. In the event subsurface conduits are exposed to vehicular traffic, concrete encasement shall be included.