UL 1238:2022 pdf free download – STANDARD FOR SAFETY Control Equipment for Use with Flammable Liquid and LP-Gas Dispensing Devices.
8.5 For a raintight enclosure, all openings for conduit shall be threaded. For a rainproof enclosure, all openings shall be threaded, unless they are located wholly below the lowest terminal lug or other live part within the enclosure, and there shall be provision for drainage of the enclosure when knockouts or unthreaded holes are provided.
8.6 A component (such as a gasket, printer door or lock cover) of an elastomeric or thermoplastic material, or a composition gasket utilizing an elastomeric material employed to make an enclosure rainproof or raintight, shall be resistant to aging. See 38.2 and 38.3. If an adhesive is used to hold the gasket in place, the gasket and adhesive shall be subjected to the Adhesion Test in the Standard for Gaskets and Seals, UL 157.
8.7 A raintight or rainproof enclosure of sheet steel having an average thickness less than 0.120 inch (3
mm)(No. 10 MSG) shall be:
a) Galvanized by the hot-dip process after forming and assembly,
b) Made from hot-dipped sheets,
c) Provided with a metallic coating that has been evaluated as at least the equivalent of zinc applied by the hot-dip process, or
d) Protected from corrosion by some other finish that has been evaluated as equivalent protection.
8.8 A raintight or rainproof enclosure made of sheet steel having an average thickness of 0.120 inch (3 mm) (No. 10 MSG) or more can be formed from either hot-dipped or electroplated sheets, or can be protected from corrosion by some other finish that has been evaluated as equivalent protection. A cadmium coating shall not be less than 0.001 inch (0.03 mm) thick.
9 Operating Mechanism
9.1 The operating mechanism of control equipment shall be such that it is not adversely affected by the vibration of normal operation. When screws and nuts serve to attach operating parts to movable members, they shall be upset or otherwise locked to prevent loosening under the conditions of actual use. The operating mechanism shall not subject manually operated switch parts to undue stress.
9.2 If the position of an operating handle is not readily apparent, the position shall be marked in accordance with 49.14.
9.3 Control equipment involving electronic control circuits shall be investigated under conditions of actual service to determine when it complies with all applicable requirements.
10 Corrosion Protection
10.1 For enclosures for outdoor use only, iron and steel parts, except bearings, thermal elements, etc., where such protection is impracticable, shall be protected against corrosion by enameling, galvanizing, sherardizing, plating, or other means that has been determined to be equivalent.
10.2 The requirement of 10.1 applies to all enclosing cases whether of sheet steel or cast iron, and to all springs and other parts upon which proper mechanical operation depends. It does not apply to small minor parts of iron or steel such as washers, screws, bolts, and similar parts which are not current-carrying, when the failure of such unprotected parts would probably not result in a hazardous condition; however the protection of all such parts is recommended. Parts made of stainless steel (properly polished or treated when required) do not require additional protection against corrosion.