422.16(B)(2) Built-in Dishwashers and Trash Compactors.
Code Change Summary: The rules pertaining to the cord-and plug-connection of built-in dishwashers and trash compactors have been separated.
In the 2014 NEC® Section 422.16(B)(2) provided one set of rules that could be applied to built-in dishwashers or trash compactors. These rules provided details on allowable cord length, receptacle location and type of attachment plug permitted.
In the 2017 NEC®, changes occurred that align the NEC® rules for built-in dishwashers with UL 749 which is the Standard for Household Dishwashers. UL 749 requires the installation instructions for a household dishwasher to state that the power supply receptacle for the dishwasher must be installed in a cabinet or on a wall adjacent to the under counter space in which the appliance is to be installed. As well, Section 210.50(C) allows appliance receptacle outlets installed in a dwelling unit for specific appliances to be installed up to 6 feet away from the intended location of the appliance.
The rules in 422.16(B)(2) allowed a cord not longer than 4 feet which made it difficult to comply with the language in the UL Standard and 210.50(C).
In the 2017 NEC®, the revised language allows a built-in dishwasher to have a cord length between 3 feet and up to 6.5 feet. As well, new item 6 states that the receptacle for a built-in dishwasher shall be located in the space adjacent to the space occupied by the dishwasher.
Below is a preview of the NEC®. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2017 NEC® edition of NFPA 70.
2014 Code Language:
422.16(B)(2) Built-in Dishwashers and Trash Compactors. Built-in dishwashers and trash compactors shall be permitted to be cord-and-plug-connected with a flexible cord identified as suitable for the purpose in the installation instructions of the appliance manufacturer where all of the following conditions are met:
(1) The flexible cord shall be terminated with a grounding-type attachment plug.
Exception: A listed dishwasher or trash compactor distinctly marked to identify it as protected by a system of double insulation, or its equivalent, shall not be required to be terminated with a grounding-type attachment plug.
(2) The length of the cord shall be 0.9 m to 1.2 m (3 ft to 4 ft) measured from the face of the attachment plug to the plane of the rear of the appliance.
(3) Receptacles shall be located to avoid physical damage to the flexible cord.
(4) The receptacle shall be located in the space occupied by the appliance or adjacent thereto.
(5) The receptacle shall be accessible.
2017 Code Language:
422.16(B)(2) Built-in Dishwashers and Trash Compactors. Built-in dishwashers and trash compactors shall be permitted to be cord-and- plug-connected with a flexible cord identified as suitable for the purpose in the installation instructions of the appliance manufacturer where all of the following conditions are met:
(1) The flexible cord shall be terminated with a grounding-type attachment plug.
Exception: A listed dishwasher or trash compactor distinctly marked to identify it as protected by a system of double insulation shall not be required to be terminated with a grounding-type attachment plug.
(2) For a trash compactor, the length of the cord shall be 0.9 m to 1.2 m (3 ft to 4 ft) measured from the face of the attachment plug to the plane of the rear of the appliance.
(3) For a built-in dishwasher, the length of the cord shall be 0.9 m to 2.0 m (3 ft to 6.5 ft) measured from the face of the attachment plug to the plane of the rear of the appliance.
(4) Receptacles shall be located to protect against physical damage to the flexible cord.
(5) The receptacle for a trash compactor shall be located in the space occupied by the appliance or adjacent thereto.
(6) The receptacle for a built-in dishwasher shall be located in the space adjacent to the space occupied by the dishwasher.
(7) The receptacle shall be accessible.