UL 399:2020 pdf download.STANDARD FOR SAFETY-Drinking Water Coolers.
1.1 These requirements cover self-contained drinking-water coolers employing hermetic refrigerant motor-compressors or thermoelectric water chilling systems and designed for connection to alternating- current circuits rated not greater than 600 volts in accordance with the National Electrical Code, NFPA 70. The following types of water coolers are included within the scope of this Standard:
a) Those supplying cold water or both cold and hot water;
b) Battery operated;
c) Those employing flammable refrigerant as defined in Supplement SB; and
d) Those provided with ultraviolet (UV) radiation lamp systems in which the UV wavelengths are 200 nm or greater; however, the effectiveness of the water treatment by the UV radiation is not covered by these requirements.
1.2 These requirements do not include additional requirements applicable to equipment designed for use in hazardous locations as defined in the National Electrical Code, NFPA 70.
1.3 A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire, electric shock, or injury to persons shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the acceptable level of safety as originally anticipated by the intent of this standard. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this standard cannot be judged to comply with this standard. Where considered appropriate, revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard.
2 Units of measurement
2.1 If a value for measurement is followed by value in other units in parentheses, the second value may
be only approximate. The first stated value is the requirement.
3 Undated references
3.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be interpreted as referring to the latest edition of that code or standard.
4 Reserved for future use
5 Glossary
5.1 For the purpose of this standard, the following definitions apply.
5.2 ACCESSORY — An optional electrical device or other component, such as a superstructure, intended for installation in or connection to a water cooler for the purpose of modifying or supplementing the functions of the water cooler. It may be factory installed or intended for installation by the user.
5.3 *ADJUSTABLE SPEED DRIVE — A combination of power converter, inverter, motor, and motormounted auxiliary devices such as encoders, tachometers, thermal switches and detectors, air blowers, heaters, and vibration sensors.UL 399 pdf download.