UL-1917:2013 pdf free download – STANDARD FOR SAFETY Solid-State Fan Speed Controls.
b) Securing such parts and insulating them from the mounting surface by a barrier, or the equivalent, or by through air or over surface spacings specified elsewhere in this standard.
13 Internal Wiring
13.1 General
13.1.1 The wiring and connections between parts of the equipment shall be protected from mechanical damage during installation.
13.1.2 The insulation on all internal wires of the equipment shall be rated for the voltage and the temperature conditions of use. It shall also be considered with respect to other conditions of service to which it is likely to be subjected. Insulation shall be at least 1/32 inch (0.8 mm) thick if the internal wiring is subjected to movement, flexing, handling, or manipulation during its intended use, or during mechanical maintenance.
13.2 Routing of internal wiring
13.2.1 A hole through which insulated wires pass in a sheet metal wall within the enclosure of the equipment shall be provided with a smooth, well-rounded bushing or shall have smooth, well-rounded surfaces upon which the wires may bear to reduce the risk of abrasion of the insulation.
13.2.2 Wires shall be routed away from sharp edges, screw threads, burrs, fins, moving parts, drawers, and the like, that can abrade the wire insulation.
13.3 Clamps and guides
13.3.1 Clamps and guides, either metallic or nonmetallic, used for routing stationary internal wiring shall be provided with smooth, well-rounded edges. The clamping action and bearing surface shall be such that abrasion or cold flow of the insulation cannot occur. Auxiliary nonconducting mechanical protection shall be provided under a metallic clamp that exerts pressure on a conductor having thermoplastic insulation less than 1/32 inch (0.8 mm) thick and having no overall braid.
13.4 Insulating bonding and grounding conductors
13.4.1 Insulated grounding and bonding conductors shall be identified by the color green with or without one or more yellow stripes. No other leads shall be so identified in the field wiring area.
13.5 Splices and connections
13.5.1 All splices and connections shall be mechanically secure and shall provide electrical continuity.
13.5.2 Electrical connections shall be soldered, welded, crimped, or otherwise securely connected. A soldered joint shall be mechanically secure before soldering.
Exception: Leads inserted through printed wiring board traces are not required to be mechanically secured before soldering.
13.6 Splice insulation
13.6.1 A splice shall be provided with insulation equivalent to that of the wires involved.
13.6.2 In determining if splice insulation consisting of coated-fabric, thermoplastic, or other types of tubing is acceptable, consideration is to be given to electrical and mechanical properties including dielectric voltage-withstand ability, heat resistance, and moisture resistance. Thermoplastic tape shall not be wrapped over a sharp edge or connection.