UL 884-2016 pdf download

UL 884-2016 pdf download.Underfloor Raceways and Fittings.
12.3 Permanent distortion is not acceptable in any duct that is for mounting on supports.
13 Loading Test
13.1 For duct Intended and marked for specific installations in accordance with 20,2.5. the following loading test is to be conducted in addition to the Torque Test described in Section 12. A vertical load of 500 lbf (2224 N or 227 kgf) is to be applied for 60 seconds to the center ot a cell on a specimen of the duct that is at least 5 ft (1.5 m) long and placed flat on a concrete floor or other solid horizontal surface. In the case of a multicellular duct, the cell that is most likely to deform permanently is the cell that is to be tested. The load is to be applied at a point no closer than 1 ft (305 mm) to one end of the duct. The application means is to be a round solid steel cylinder having a diameter of 2 inches (50.8 mm) with flat ends that are perpendicular to the longitudinal axis of the cylinder. The cylinder is to be stood on end on the duct with its longitudinal axis vertical. The load is to be applied vertically downward through the longitudinal axis of the cylinder by means of a weight or by machine.
13.2 The application of the load shall not result in permanent deformation greater than 118 in (3 mm).
14 Grounding Continuity Test
14.1 As specified in 5.1, a fitting is to be assembled to a section of duct in the intended manner, and a direct current of 30 A is to be passed from the duct to the fitting. The resulting drop in potential is to be measured between a point (file mark) on the duct 1/16 inch (1.5 mm) from the connection and a similar point on the titling. The resistance in ohms is to be determined by dividing the drop in potential in volts by the current In amperes passing through the connection.
14.2 The resistance of the connection of duct with a fining shall not exceed 0.005 ohm.
15 Protective Coatings Tests
15.1 ZInc
15.1i The zinc coating on a specimen cut from finished duct shall not show a bright, adherent deposit of copper after whichever of the following number of Immersions in a solution of copper sulphate is applicable to the construction:
a) Two immersions for duct that Is marked (see 20.2.6) for installation not on grade and only In concrete;
b) Four immersions for all other duct.
15.1.2 The solution of copper sulphate is to be made from distilled water and the American Chemical Society (ACS) reagent grade of cupric sulphate (CuSO4). In a copper container or in a glass. polyethylene, or other chemically nonreactive container in which a bright piece of copper is present. a quantity of the cupac sulphate is to be dissolved in hot distilled water to obtain a solution that has specific gravity slightly higher than 1.186 after the solution is cooled to a temperature at 18.3°C (65.0°F). Any free acid that might be present Is to be neutralized by the addition of approximately 1 g of cupric oxide (CuO) or 1 g of cupric hydroxide [Cu(OH)2J per liter of solution. The solution is to be diluted with distilled water to obtain a specific gravity of exactly 1.186 at a temperature of 18.3°C (65.0°F). The solution is then to be filtered.
15.1.3 The 6-inch (150-mm) specimens are to be cut from a sample length of finished raceway. With prudent attention to health and lire risks, the specimens are to be cleaned with an organic solvent,
15.1.4 Each specimen is to be examined tor evidence of damage to the zinc coating. and only specimens that are not damaged are to be selected for use in the test.
15.1.5 The selected specimens are to be rinsed in water, and all surfaces are to be dried with clean cheesecloth. As much of the water as possible is to be removed in the drying operation, because water slows the reaction between the zinc and the solution, thereby adversely affecting the test results. The surface of the zinc is to be dry and clean before a specimen is immersed in the copper sulphate solution. The specimens are not to be touched by hands or anything else that can contaminate or damage the surfaces.