UL 250:2000 pdf download.Household Refrigerators and Freezers.
4.9.3 Permanently-connected refrigerators
4.9.3.1 A refrigerator intended for permanent connection to the power supply shall have provision for connection of one of the wiring systems that, in accordance with the Canadian Electrical Code, Part I, GSA Standard C22.2. 1990 and the National Electrical Code. ANSLNFPA 70-1993. would be acceptable for the appliance.
4.9.3.2 Refrigerated kitchen units shall have provision for permanent connection to the power supply.
4,9.3.3 A refrigerator intended for permanent connection to the power supply shall have as a provision for grounding an equipment grounding terminal or lead.
4.9.3,4 Sheet metal to which a winng system is to be connected in the field shall have a thickness not less than 0.81 mm (0.032 inch) if uncoated steel, not less than 0.86 mm (0.034 inch) if galvanized steel. arid not less than 1.14 mm (0.045 inch) if nonferrous.
4.9.3.5 If threads for the connection of conduit are tapped all the way through a hole in an enclosure wall, or it an equivalent construction is employed, there shall be not less than three nor more than five threads in the metal, and the construction of the device shall be such that a conduit bushing can be attached. If threads for the connection of conduit are not tapped all the way through a hole in an enclosure wall, conduit hit, or the like, there shall be not less than 3-1/2 threads in the metal, and there shall be a smooth, rounded inlet hole for the conductors that shall (1) afford protection to the conductor equivalent to that provided by a standard conduit bushing and (2) have an internal diameter approximately the same as that of the corresponding trade size of rigid conduit.
4.9.3.6 A knockout for connection of a field-wiring system to a field-wiring compartment shall accommodate not less than 12.7 mm (0.5 inch) trade size conduit.
4.9.3.1 A refrigerator intended for permanent connection to the power supply shall have provision for connection of one of the wiring systems that, in accordance with the Canadian Electrical Code, Part I, GSA Standard C22.2. 1990 and the National Electrical Code. ANSLNFPA 70-1993. would be acceptable for the appliance.
4.9.3.2 Refrigerated kitchen units shall have provision for permanent connection to the power supply.
4,9.3.3 A refrigerator intended for permanent connection to the power supply shall have as a provision for grounding an equipment grounding terminal or lead.
4.9.3,4 Sheet metal to which a winng system is to be connected in the field shall have a thickness not less than 0.81 mm (0.032 inch) if uncoated steel, not less than 0.86 mm (0.034 inch) if galvanized steel. arid not less than 1.14 mm (0.045 inch) if nonferrous.
4.9.3.5 If threads for the connection of conduit are tapped all the way through a hole in an enclosure wall, or it an equivalent construction is employed, there shall be not less than three nor more than five threads in the metal, and the construction of the device shall be such that a conduit bushing can be attached. If threads for the connection of conduit are not tapped all the way through a hole in an enclosure wall, conduit hit, or the like, there shall be not less than 3-1/2 threads in the metal, and there shall be a smooth, rounded inlet hole for the conductors that shall (1) afford protection to the conductor equivalent to that provided by a standard conduit bushing and (2) have an internal diameter approximately the same as that of the corresponding trade size of rigid conduit.
4.9.3.6 A knockout for connection of a field-wiring system to a field-wiring compartment shall accommodate not less than 12.7 mm (0.5 inch) trade size conduit.
