UL 1472-2020 pdf download

UL 1472-2020 pdf download.Solid-State Dimming Controls.
Electronic ballast – A ballast, generally involving high-frequency switching that is controlled by active components (transistors, thyristors, and the like), and with the lamp ballasting impedance provided by a series capacitive or inductive reactance appropriate for the high switching frequency. “Ballast” also refers to other drivers or supplies that operate lamp technologies other than fluorescent. Electronic switch – A solid-state device that performs strictly an on-off function and meets the requirements of this standard including the air-gap switch requirement. Grounding/bonding conductor – A conductor that is defined in the National Electrical Code (NEC) as an Equipment Grounding Conductor, and a conductor that is defined in the Canadian Electrical Code (CE Code), Part I, as a Bonding Conductor. Lamp, self-ballasted – A device such as a CFL, CCFL, LED, etc. that is provided with a lamp base and incorporating a nonreplaceable light source and any additional elements such as an electronic ballast necessary for starting and stabilizing operation of the light source, which cannot be dismantled without being permanently damaged. Off position – The air-gap switch is in the open position. Opposite polarity – A difference of potential between two points where shorting of these two points would result in a condition involving overload, rupturing of printed wiring board tracks, components, fuses, or the like. Touch dimmer – A device using circuitry for touch actuation in accordance with Clauses 4.9 and 5.13. Examples of such circuitry are non-isolated sensing or conductively connected dead metal. Type I dimmer – A dimmer in which the air-gap switch is used to energize preset lighting levels. Type II dimmer – UL A dimmer with an air-gap switch that opens and closes the load circuit at the minimum output voltage setting only.
4 Construction 4.1 Polymeric materials 4.1.1 A polymeric material used for electrical insulation or as an enclosure part shall have a flammability class rating of 5VA, 5VB, V-0, V-1, or V-2 in accordance with UL 94 and C22.2 No. 0.17. The flammability class rating shall be investigated at the nominal minimum thickness of a polymeric material used within 0.8 mm (1/32 inch) of uninsulated live parts. Exception No. 1: A polymeric material that complies with either the 12 mm or 3/4 inch flame flammability test described in UL 746C and C22.2 No. 17, need not have a flammabilityclass rating. Exception No. 2: If the polymeric material is not used in place of the spacings specified in Table 4, a polymeric material used in a rearhousing totally contained within the volume ofthe outlet box may have a minimum flammabilityclass rating ofHB. 4.1.2 A polymeric material used for electrical insulation or as an enclosure part shall have a performance level category (PLC), determined in accordance with UL 746C, that complies with the requirements specified in Table 1 for electrical insulation or Table 2 for enclosure parts, respectively. Exception No. 1: A polymeric material that complies with the requirements in UL 746C is considered to complywith both Table 1 and Table 2. Exception No. 2: Ifthe spacings to a polymeric material used as an enclosure part are not greaterthan the through-air and over-surface spacings specified in Table 4, the polymeric material shall comply with both Table 1 and Table 2. Exception No. 3: If the polymeric material is not used in place of the spacings specified in Table 4, a polymeric material that does not contact uninsulated live parts and that is used as a rear housing totally contained within the volume ofthe outlet box need not complywith the performance level categories.
4.2.2 An actuating member of conductive material shall be insulated from live parts. 4.2.3 A dimmer provided with a field replaceable actuator assembly shall not permit contact to be made between the probe shown in Figure 2 and any live part when the actuator assembly is removed. Compliance is checked by inspection and if necessary, the field replaceable actuator assembly test, Clause 5.15. 4.2.4 A dimmer provided with a field replaceable actuator assembly that remains operational (capable of switching the load “on” or changing the light output) without the actuator assembly installed, shall also comply with the limited short-circuit test with the actuator assembly removed. See Clause 5.10.6. Exception: A dimmer provided with cosmetic or decorative type actuator, such as a knob attached to the stem ofa dimmer, ora decorative type actuatorthat, when removed, renders the dimmerinoperable, is not required to complywith the short circuit test with the cosmetic ordecorative actuatorfeature removed.
UL 1472-2020 pdf download.