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in compliance with 110.25. Informational Note: See 422.34 for appliances employing unit switches. Motor-Operated Appliances Rated over 1⁄8 Horsepower. The disconnecting means shall comply with 430.109 and 430.110. For permanently connected motor-operated appliances with motors rated over 1⁄8 hp...

in compliance with 110.25. Informational Note: See 422.34 for appliances employing unit switches. Motor-Operated Appliances Rated over 1⁄8 Horsepower. The disconnecting means shall comply with 430.109 and 430.110. For permanently connected motor-operated appliances with motors rated over 1⁄8 hp, the disconnecting means shall be within sight from the appliance or be capable of being locked in the open position in compliance with 110.25. Exception: If an appliance is provided with a unit switch that complies with 422.34(A), (B), or (C), the switch or circuit breaker serving as the other disconnecting means shall be permitted to be out of sight from the appliance. 422.33 Disconnection of Cord-and-Plug-Connected or Attachment Fitting–Connected Appliances. (A) Separable Connector or an Attachment Plug (or Attachment Fitting) and Receptacle. For cord-and-plug- (or attachment fitting–) connected appliances, an accessible separable connector or an accessible plug (or attachment fitting) and receptacle combination shall be permitted to serve as the disconnecting means. The attachment fitting shall be a factory installed part of the appliance and suitable for disconnection of the appliance. Where the separable connector or plug (or attachment fitting) and receptacle combination are not accessible, cord-and-plug-connected or attachment fitting-and-plug-connected appliances shall be provided with disconnecting means in accordance with 422.31. Connection at the Rear Base of a Range. For cord-and-plug-connected household electric ranges, an attachment plug and receptacle connection at the rear base of a range, accessible from the front by removal of a drawer, shall be permitted. Rating. The rating of a receptacle or of a separable connector shall not be less than the rating of any appliance connected thereto. Exception: Demand factors authorized elsewhere in this Code shall be permitted to be applied to the rating of a receptacle or of a separable connector. 422.34 Unit Switch(es) as Disconnecting Means. A unit switch(es) with a marked-off position that is a part of an appliance and disconnects all ungrounded conductors shall be permitted as the disconnecting means required by this article where other means for disconnection are provided in occupancies specified in 422.34(A) through (D). Multifamily Dwellings. In multifamily dwellings, the other disconnecting means shall be within the dwelling unit, or on the same floor as the dwelling unit in which the appliance is installed, and shall be permitted to control lamps and other appliances. Two-Family Dwellings. In two-family dwellings, the other disconnecting means shall be permitted either inside or outside of the dwelling unit in which the appliance is installed. In this case, an individual switch or circuit breaker for the dwelling unit shall be permitted and shall also be permitted to control lamps and other appliances. One-Family Dwellings. In one-family dwellings, the service disconnecting means shall be permitted to be the other disconnecting means. Other Occupancies. In other occupancies, the branch-circuit switch or circuit breaker, where readily accessible for servicing of the appliance, shall be permitted as the other disconnecting means. 422.35 Switch and Circuit Breaker to Be Indicating. Switches and circuit breakers used as disconnecting means shall be of the indicating type. Part IV. Construction 422.40 Polarity in Cord-and-Plug-Connected Appliances. If the appliance is provided with a manually operated, line-connected, single-pole switch for appliance on–off operation, an Edison-base lampholder, or a 15- or 20-ampere receptacle, the attachment plug shall be of the polarized or grounding type. A 2-wire, nonpolarized attachment plug shall be permitted to be used on a listed double-insulated shaver. Informational Note: See 410.82 for polarity of Edison-base lampholders. 422.41 Cord-and-Plug-Connected Appliances Subject to Immersion. Cord-and-plug-connected portable, freestanding hydromassage units and hand-held hair dryers shall be constructed to provide protection for personnel against electrocution when immersed. ENHANCED CONTENT Collapse Although receptacles in bathrooms of dwelling units have been required to be protected by GFCIs since the 1975 edition of the NEC, many receptacles in older existing bathrooms are not so protected. Cord-and-plug-connected appliances, such as handheld hair dryers, can fall into bathtubs and cause fatalities. Therefore, they are required to be provided with some form of protective device that is part of the appliance. Three types of protectors comply with this requirement: Appliance-leakage circuit interrupters (ALCIs) Immersion-detector circuit interrupters (IDCIs) Ground-fault circuit interrupters (GFCIs) ALCIs de-energize the supply to the appliance when leakage current exceeds a predetermined value. IDCIs de-energize the supply when a liquid causes a conductive path between a live part and a sensor, and GFCIs de-energize the supply when the current to ground exceeds a predetermined value. 422.42 Signals for Heated Appliances. In other than dwelling-type occupancies, each electrically heated appliance or group of appliances intended to be applied to combustible material shall be provided with a signal or an integral temperature-limiting device. ENHANCED CONTENT Collapse Many electrically heated appliances in commercial or industrial locations use a red light, connected to and within sight of the appliance, to indicate that the appliance is energized and operating. No signal is required for an electrically heated appliance provided with an integral high-temperature-limiting device, such as a thermostat, that limits the temperature to which the appliance can heat. 422.44 Cord-and-Plug-Connected Immersion Heaters. Electric heaters of the cord-and-plug-connected immersion type shall be constructed and installed so that current-carrying parts are effectively insulated from electrical contact with the substance in which they are immersed. 422.45 Stands for Cord-and-Plug-Connected Appliances. Each smoothing iron and other cord-and-plug-connected electrically heated appliance intended to be applied to combustible material shall be equipped with an approved stand, which shall be permitted to be a separate piece of equipment or a part of the appliance. 422.47 Water Heater Controls. All storage or instantaneous-type water heaters shall be equipped with a temperature-limiting means in addition to its control thermostat to disconnect all ungrounded conductors. Such means shall comply with both of the following: (1) Installed to sense maximum water temperature. Be either a trip-free, manually reset type or a type having a replacement element. Exception No. 1: Storage water heaters that are identified as being suitable for use with a supply water temperature of 82°C (180°F) or above and a capacity of 60 kW or above. Exception No. 2: Instantaneous-type water heaters that are identified as being suitable for such use, with a capacity of 4 L (1 gal) or less. 422.48 Infrared Lamp Industrial Heating Appliances. (A) 300 Watts or Less. Infrared heating lamps rated at 300 watts or less shall be permitted with lampholders of the medium-base, unswitched porcelain type or other types identified as suitable for use with infrared heating lamps rated 300 watts or less. Over 300 Watts. Screw shell lampholders shall not be used with infrared lamps rated over 300 watts, unless the lampholders are identified as being suitable for use with infrared heating lamps rated over 300 watts. ENHANCED CONTENT Collapse Infrared (heat) radiation lamps are tungsten-filament incandescent lamps similar in appearance to lighting lamps. However, they are designed to operate at a lower temperature, thus transferring more heat radiation and less light intensity. Infrared lamps are used for a variety of heating and drying purposes in industrial locations. Part V. Marking 422.60 Nameplate. (A) Nameplate Marking. Each electrical appliance shall be provided with a nameplate giving the identifying name and the rating in volts and amperes, or in volts and watts. If the appliance is to be used on a specific frequency or frequencies, it shall be so marked. Where motor overload protection external to the appliance is required, the appliance shall be so marked. Informational Note: See 422.11 for overcurrent protection requirements. (B) To Be Visible. Marking shall be located so as to be visible or easily accessible after installation. 422.61 Marking of Heating Elements. All heating elements that are rated over one ampere, replaceable in the field, and a part of an appliance shall be legibly marked with the ratings in volts and amperes, or in volts and watts, or with the manufacturer’s part number. 422.62 Appliances Consisting of Motors and Other Loads. (A) Nameplate Horsepower Markings. Where a motor-operated appliance nameplate includes a horsepower rating, that rating shall not be less than the horsepower rating on the motor nameplate. Where an appliance consists of multiple motors, or one or more motors and other loads, the nameplate value shall not be less than the equivalent horsepower of the combined loads, calculated in accordance with 430.110(C)(1). Additional Nameplate Markings. Appliances, other than those factory-equipped with cords and attachment plugs and with nameplates in compliance with 422.60, shall be marked in accordance with 422.62(B)(1) or (B)(2). Marking. In addition to the marking required in 422.60, the marking on an appliance consisting of a motor with other load(s) or motors with or without other load(s) shall specify the minimum supply circuit conductor ampacity and the maximum rating of the circuit overcurrent protective device. This requirement shall not apply to an appliance with a nameplate in compliance with 422.60 where both the minimum supply circuit conductor ampacity and maximum rating of the circuit overcurrent protective device are not more than 15 amperes. Alternate Marking Method. An alternate marking method shall be permitted to specify the rating of the largest motor in volts and amperes, and the additional load(s) in volts and amperes, or volts and watts in addition to the marking required in 422.60. The ampere rating of a motor 1⁄8 horsepower or less or a nonmotor load 1 ampere or less shall be permitted to be omitted unless such loads constitute the principal load. Article 424 Fixed Electric Space-Heating Equipment Part I. General 424.1 Scope. This article covers fixed electric equipment used for space heating. For the purpose of this article, heating equipment includes heating cables, unit heaters, boilers, central heating systems, or other fixed electric space-heating equipment. This article does not apply to process heating and room air conditioning. 424.3 Other Articles. Fixed electric space-heating equipment incorporating a hermetic refrigerant motor-compressor shall additionally comply with Table 424.3unless amended by this article. Table 424.3 Other Articles Equipment Article Air-conditioning and refrigerating equipment 440 (Parts I, II, III, IV, V, VI) 424.4 Branch Circuits. (A) Branch-Circuit Requirements. An individual branch circuit shall be permitted to supply any volt-ampere or wattage rating of fixed electric space-heating equipment for which the branch circuit is rated. Branch circuits supplying two or more outlets for fixed electric space-heating equipment shall be rated not over 30 amperes. In other than a dwelling unit, fixed infrared heating equipment shall be permitted to be supplied from branch circuits rated not over 50 amperes. Branch-Circuit Conductor Sizing. The branch-circuit conductor(s) ampacity shall not be less than 125 percent of the load of the fixed electric space-heating equipment and any associated motor(s). ENHANCED CONTENT Collapse Branch-circuit conductors supplying fixed electric space-heating equipment must be sized at 125 percent of the total load of the heaters (and motors) to protect conductors from overheating during periods of prolonged operation. 424.6 Listed Equipment. Electric baseboard heaters, heating cables, duct heaters, and radiant heating systems shall be listed and labeled. Part II. Installation 424.10 General. Factory-installed receptacle outlets that are part of a permanently installed electric baseboard heater, or outlets provided as a separate listed assembly of an electric baseboard heater, shall be permitted in lieu of a receptacle outlet(s) that is required by 210.52. Such receptacle outlets shall not be connected to the baseboard heater circuits. Informational Note: Listed baseboard heaters include instructions that may not permit their installation below receptacle outlets. ENHANCED CONTENT Collapse This restates the permission granted in the second paragraph of 210.52 — that is, it allows factory-installed receptacle outlets in electric baseboard heaters to satisfy the spacing requirements for receptacle outlets in dwelling units according to 210.52(A). Heating equipment and systems often have special installation instructions for spacings, types of supply wires, or special control equipment, which must be considered in determining the installation’s suitability. 424.11 Supply Conductors. Fixed electric space-heating equipment requiring supply conductors with an insulation rating greater than 60°C shall be clearly and permanently marked. This marking shall be plainly visible after installation and shall be permitted to be adjacent to the field connection box. ENHANCED CONTENT Collapse Fixed electric space-heating equipment may require supply conductors with a temperature rating greater than 60°C, due to their proximity to the heating elements and the installation instructions provided with a listed product. 424.12 Locations. (A) Exposed to Physical Damage. Where subject to physical damage, fixed electric space-heating equipment shall be protected in an approved manner. Damp or Wet Locations. Heaters and related equipment installed in damp or wet locations shall be listed for such locations. Informational Note No. 1: See 110.11 for equipment exposed to deteriorating agents. Informational Note No. 2: See 680.27(C) for pool deck areas. 424.13 Spacing from Combustible Materials. Fixed electric space-heating equipment shall be installed to provide the required spacing between the equipment and adjacent combustible material, unless it is listed to be installed in direct contact with combustible material. Part III. Control and Protection of Fixed Electric Space-Heating Equipment 424.19 Disconnecting Means. Means shall be provided to simultaneously disconnect the heater, motor controller(s), and supplementary overcurrent protective device(s) of all fixed electric space-heating equipment from all ungrounded conductors. Where heating equipment is supplied by more than one source, feeder, or branch circuit, the disconnecting means shall be grouped and identified as having multiple disconnecting means. Each disconnecting means shall simultaneously disconnect all ungrounded conductors that it controls. The disconnecting means specified in 424.19(A) and (B) shall have an ampere rating not less than 125 percent of the total load of the motors and the heaters and shall be capable of being locked in the open position in compliance with 110.25. ENHANCED CONTENT Collapse If there are multiple disconnecting means, they must be grouped. Each disconnecting means must simultaneously open all the ungrounded conductors that it controls to prevent the practice of disconnecting one conductor at a time at terminal blocks or similar devices. The disconnect switch must have a rating of 125 percent of the heater’s total load. A unit switch is permitted by 424.19(C) to serve as the disconnecting means, provided that it has a marked “off” position and disconnects all ungrounded conductors. In addition, other means must be provided in accordance with 424.19(C)(1) through (C)(4). Such other means are not required to be capable of being locked in the open position. Heating Equipment with Supplementary Overcurrent Protection. The disconnecting means for fixed electric space-heating equipment with supplementary overcurrent protection shall be within sight from the supplementary overcurrent protective device(s), on the supply side of these devices, if fuses, and, in addition, shall comply with either 424.19(A)(1) or (A)(2). Heater Containing No Motor Rated over 1⁄8 Horsepower. The disconnecting means provided shall be within sight from the motor controller(s) and the heater, or shall be lockable as specified in 424.19, or shall be a unit switch complying with 424.19(C). Heater Containing a Motor(s) Rated over 1⁄8 Horsepower. The disconnecting means required by 424.19 shall be permitted to serve as the required disconnecting means for both the motor controller(s) and heater under either of the following conditions: Where the disconnecting means is in sight from the motor controller(s) and the heater and complies with Part IX of Article 430. Where a motor(s) of more than 1⁄8 hp and the heater are provided with a single unit switch that complies with 422.34(A), (B), (C), or (D), the disconnecting means shall be permitted to be out of sight from the motor controller. Heating Equipment Without Supplementary Overcurrent Protection. Without Motor or with Motor Not over 1⁄8 Horsepower. For fixed electric space-heating equipment without a motor rated over 1⁄8 hp, the branch-circuit switch or circuit breaker shall be permitted to serve as the disconnecting means where the switch or circuit breaker is within sight from the heater or is capable of being locked in the open position in compliance with 110.25. Over 1⁄8 Horsepower. For motor-driven electric space-heating equipment with a motor rated over 1⁄8 hp, a disconnecting means shall be located within sight from the motor controller or shall be permitted to comply with the requirements in 424.19(A)(2). Unit Switch(es) as Disconnecting Means. A unit switch(es) with a marked “off” position that is part of a fixed heater and disconnects all ungrounded conductors shall be permitted as the disconnecting means required by this article where other means for disconnection are provided in the types of occupancies in 424.19(C)(1) through (C)(4). Multifamily Dwellings. In multifamily dwellings, the other disconnecting means shall be within the dwelling unit, or on the same floor as the dwelling unit in which the fixed heater is installed, and shall also be permitted to control general-purpose circuits and appliance circuits. Two-Family Dwellings. In two-family dwellings, the other disconnecting means shall be permitted either inside or outside of the dwelling unit in which the fixed heater is instal⁠led. In this case, an individual switch or circuit breaker for the dwelling unit shall be permitted and shall also be permitted to control general-purpose circuits and appliance circuits. One-Family Dwellings. In one-family dwellings, the service disconnecting means shall be permitted to be the other disconnecting means. Other Occupancies. In other occupancies, the branch-circuit switch or circuit breaker, where readily accessible for servicing of the fixed heater, shall be permitted as the other disconnecting means. 424.20 Thermostatically Controlled Switching Devices. (A) Serving as Both Controllers and Disconnecting Means. Thermostatically controlled switching devices and combination thermostats and manually controlled switches shall be permitted to serve as both controllers and disconnecting means, provided they meet all of the following conditions: (1) Provided with a marked “off” position Directly open all ungrounded conductors when manually placed in the “off” position Designed so that the circuit cannot be energized automatically after the device has been manually placed in the “off” position Located as specified in 424.19 Located in an accessible location Thermostats That Do Not Directly Interrupt All Ungrounded Conductors. Thermostats that do not directly interrupt all ungrounded conductors and thermostats that operate remote-control circuits shall not be required to meet the requirements of 424.20(A). These devices shall not be permitted as the disconnecting means. 424.21 Switch and Circuit Breaker to Be Indicating. Switches and circuit breakers used as disconnecting means shall be of the indicating type. 424.22 Overcurrent Protection. (A) Branch-Circuit Devices. Electric space-heating equipment, other than motor-operated equipment required to have additional overcurrent protection by Parts III and IV of Article 430 or Parts III and VI of Article 440, shall be permitted to be protected against overcurrent where supplied by one of the branch circuits in Part II of Article 210. Resistance Elements. Resistance-type heating elements in electric space-heating equipment shall be protected at not more than 60 amperes. Equipment rated more than 48 amperes and employing such elements shall have the heating elements subdivided, and each subdivided load shall not exceed 48 amperes. Where a subdivided load is less than 48 amperes, the rating of the supplementary overcurrent protective device shall comply with 424.4(B). A boiler employing resistance-type immersion heating elements contained in an ASME-rated and stamped vessel shall be permitted to comply with 424.72(A). ENHANCED CONTENT Collapse The reason for subdividing the overcurrent protection is to minimize the amount of damaging energy — in the form of both heat and magnetic energy — released into the heating elements during a short circuit. The damaging short-circuit energy released at the element is greatly reduced by limiting the size of the overcurrent device protecting the individual heating elements, thereby greatly reducing the risk of fire. In addition, a second benefit may be continuity of service if equipment is only partially affected. Historically, the subdivision size of 60 amperes was selected to use the maximum fuseholder size of 60 amperes while maintaining up to a 48-ampere heating element (48 A × 125% = 60 A). Overcurrent Protective Devices. The supplementary overcurrent protective devices for the subdivided loads specified in 424.22(B) shall meet all of the following conditions: Be factory-installed within or on the heater enclosure or supplied for use with the heater as a separate assembly by the heater manufacturer Be accessible Be suitable for branch-circuit protection Where cartridge fuses are used to provide overcurrent protection for the subdivided loads, a single disconnecting means shall be permitted to be used as the disconnecting means for all of the subdivided loads. Informational Note No. 1: See 240.10. Informational Note No. 2: See 240.10 for supplementary overcurrent protection. Informational Note No. 3: See 240.40 for disconnecting means for cartridge fuses in circuits of any voltage. (D) Branch-Circuit Conductors. The conductors supplying the supplementary overcurrent protective devices shall be considered branch-circuit conductors. Where the heaters are rated 50 kW or more, the conductors supplying the supplementary overcurrent protective devices specified in 424.22(C) shall be permitted to be sized at not less than 100 percent of the nameplate rating of the heater, provided all of the following conditions are met: (1) The heater is marked with a minimum conductor size. The conductors are not smaller than the marked minimum size. A temperature-actuated device controls the cyclic operation of the equipment. Conductors for Subdivided Loads. Field-wired conductors between the heater and the supplementary overcurrent protective devices shall be sized at not less than 125 percent of the load served. The supplementary overcurrent protective devices specified in 424.22(C) shall protect these conductors in accordance with 240.4. Where the heaters are rated 50 kW or more, the ampacity of field-wired conductors between the heater and the supplementary overcurrent protective devices shall be permitted to be not less than 100 percent of the load of their re