1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULUNDERWRITERS LABORATORIES INC. CERTIFICATION REQUIREMENT DECISIONThis Certification Requirement Decision is prepared and published by Underwriters Laboratories Inc.(UL). It is normative for the a
2、pplicable UL Product Certification Program(s); however, it is currently notpart of the UL Standard(s) referenced below.Product Category (CCN): FKSZStandard Number: UL 8750Standard Title: Standard for Light Emitting Diode (LED) Equipment for Use inLighting ProductsEdition Date: September 15, 2015Edit
3、ion Number: 2Section / Paragraph Reference: Supplement SESubject: Supplement SE Requirements for Class P LED DriversDECISION:SUPPLEMENT SE - REQUIREMENTS FOR CLASS P LED DRIVERSSE1 ScopeSE1.1 These requirements apply to Class P LED drivers.SE1.2 In this supplement, the term “driver” refers to a Clas
4、s P LED driver unless otherwise noted.SE2 DefinitionsSE2.1 CLASS P LED DRIVER A LED driver that is inherently or integrally protected from overheatingunder the specified conditions of this standard.SE3 ConstructionSE3.1 A driver shall comply with all applicable construction requirements of this stan
5、dard and the followingcriteria:a) The driver shall not rely upon external overcurrent or over temperature protection forcompliance with the requirements of this standard;b) The driver shall not rely upon external thermal management methods such as forced aircooling, non-integral heat-sinking, or ext
6、ernal temperature sensors for compliance with therequirements of this standard;c) The driver shall be provided with both an integral fire and electrical enclosure in accordancewith Mechanical Construction, Section 6;d) With regard to (c), polymeric materials serving as fire or electrical enclosures
7、shall have arelative thermal index (RTI) with impact of at least 90C (194F);d) With regard to (c), polymericmaterials serving as fire or electrical enclosures shall have a relative thermal index (RTI) withimpact of at least 90C (194F);UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION O
8、RDISTRIBUTION WITHOUT PERMISSION FROM ULe) Drivers shall be provided with supply and load connection methods suitable for field wiring.The driver shall be provided with supply connections that comply with 7.4.1 and one of themethods described in 7.4.2. The driver shall be provided with load connecti
9、ons that comply with7.4.1 and 7.4.4. Additionally, integral wiring terminals and lead wires shall be suitable for atleast 90C (194F); andf) Paragraph 6.4.2 does not applySE4 PerformanceSE4.1 GeneralSE4.1.1 A driver shall comply with all applicable performance requirements of this standard and theadd
10、itional criteria in this section.SE4.1.2 During these tests a driver shall be operated in its worst-case electrical and thermal operatingcondition, as defined by its markings and electrical ratings.SE4.2 Temperature testSE4.2.1 In addition to the criteria in 8.3, the temperature on any point on the
11、exterior surface shall notexceed 90C (194F) when tested in the ambient environment in Table 8.2.SE4.3 Class P abnormal testsSE4.3.1 Test criteriaSE4.3.1.1 These requirements supplement the criteria in 8.7.1.SE4.3.1.2 During any Class P abnormal test:a) The driver shall not exhibit a risk of fire or
12、electric shock as defined in 8.7.1.3;b) The temperatures on any point on the driver enclosure shall not exceed 150C (302F); andc) If any point on the driver enclosure exceeds 110C (230F), the drivers operating time shallnot exceed the applicable time limit specified in Table SE4.1.STANDARD NUMBER: U
13、L 8750 -2-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTable SE4.1Temperature-versus-time criteriaHighest measured temperature Time limitaC (F) Minutes150 (302) 5.3145 (293) 7.1140 (284) 10135 (275) 14130 (266) 20125 (257) 31120 (248) 53115
14、 (239) 120aApply the time limit that corresponds to the highest measured temperature. Operating time is measured between the instantthe enclosure temperature exceeds 110C (230F) and either:a) The temperature drops below 110C; orb) The driver input drops to 10% or less of its rated input current, whi
15、chever comes first.SE4.3.1.3 If driver operation is interrupted by the functioning of an integral, automatically resetting(thermostatic) type protector or an equivalent electronic protective circuit:a) The locations on the enclosure that exceed 110C (230F) when the protection operates shallbe cooler
16、 than 85C (185F) when the protection resets; andb) The locations that do not exceed 110C (230F) when protection operates shall be coolerthan 100C (212F) when the protection resets.SE4.3.1.4 With regard to SE4.3.1.3, a thermostatic protector is a discrete component or electronic circuitwith a binary
17、action (ON/OFF) that disconnects a load in response to a temperature rise and thenautomatically reconnects the load once the temperature has dropped (i.e.: bimetallic thermal protectors).Electronic circuits that reduce driver output current or power to maintain a target thermal operating pointare no
18、t considered thermostatic for the purposes of these tests.SE4.3.2 Component failure test Class P LED driversSE4.3.2.1 In addition to the requirements in 8.7.2, a driver shall also comply with requirements in thissection and SE4.3.1.SE4.3.2.2 Each component fault is initially conducted in an ambient
19、temperature of 25C 5C (77F5F)and proceeds as follows:a) If it is obvious within 30 minutes of operation that a component has opened or a protectivecircuit has operated, and the driver is no longer operating, the test may be terminated;b) If after 30 minutes of operation it is determined that the enc
20、losure temperature is no longerrising and driver operation is obviously stable (no indication of imminent fire or shock risk), thetest may be terminated; orc) If the driver continues to operate after 30 minutes the test is to be stopped, the driver is to beplaced in an elevated ambient temperature o
21、ven as described in Table 8.2, and the testrestarted while monitoring temperatures on the enclosure. The test is then continued until theultimate result is known, but not exceeding 7 hours.STANDARD NUMBER: UL 8750 -3-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITH
22、OUT PERMISSION FROM ULSE4.3.2.3 Recognizing that a failure of a control or signal circuit can have an adverse effect on a powercircuit that could result in a fire or electric shock risk, the exceptions to the requirements in 8.7.2.1 are notapplicable to these drivers.SE4.3.3 Output loading tests Cla
23、ss P LED driversSE4.3.3.1 In addition to the requirements in 8.7.3 and 8.7.4, enclosure temperatures shall also complywith the time and temperature limits in SE4.3.1 during all loading tests (overload and short-circuit). Thetime and temperature limits in 8.7.3.4 are superseded by those in SE4.3.1.SE
24、4.3.4 Increased-ambient temperature test Class P LED driversSE4.3.4.1 The test is conducted under the same electrical and thermal operating conditions as theTemperature test in 8.3 and the ambient environment in Table 8.2, with thermocouples attached tomonitor the highest temperatures on the exterio
25、r of the enclosure (case temperature). The test procedurein SE4.3.4.2 SE4.3.4.6 is graphically represented by Figure SE4.1.This is generated text for figtxt.STANDARD NUMBER: UL 8750 -4-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULFigure SE4
26、.1Flowchart of the increased-ambient test Class P LED driversNote: Exhibiting a risk of fire or electric shock in any step is not acceptable and would terminate the test.STANDARD NUMBER: UL 8750 -5-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM
27、 ULSE4.3.4.2 To prepare for this test, one sample of the driver is energized and operated until its enclosurereaches a constant temperature in accordance with 8.3.6.SE4.3.4.3 The oven ambient is raised as rapidly as is convenient by 5C (9F) and driver operation ismonitored for 30 minutes. This cycle
28、 is repeated until one of the following occurs:a) The case temperature exceeds 110C (230F);b) Driver operation is interrupted by the functioning of an integral automatically resetting(thermostatic) type protector or an equivalent electronic protective circuit;c) The driver permanently ceases to func
29、tion; ord) The driver has operated in an 80C (176F) oven ambient for 30 minutes.SE4.3.4.4 If SE4.3.4.3 (a) or (b) occurs, then the 30 minute dwell time for that step is disregarded and thedriver case temperature, operating time and input current are monitored and recorded as required todetermine com
30、pliance with all test criteria in SE4.3.1. If the driver complies with SE4.3.1, the ovenambient is raised to the next temperature step and the test continued per SE4.3.4.3. If the driverpermanently ceases to function, see SE4.3.4.5.SE4.3.4.5 If SE4.3.4.3 (c) or (d) occurs and if the driver complies
31、with all test criteria in SE4.3.1, the testis terminated and the results deemed acceptable.SE4.3.4.6 If at any point in this test the driver does not comply with any part of SE4.3.1, the test isterminated and the results are considered unacceptable.SE4.3.4.7 If compliance with this test relies on th
32、e operation of an electronic circuit to interrupt or reducethe drivers output current or power, this circuit shall additionally comply with the requirements ofSupplement SA.SE4.3.4.8 Discrete components covered by the exception to 8.7.2.2 are exempt from the reliabilityinvestigation in Supplement SA
33、.SE4.4 Leakage current measurement testSE4.4.1 This test is required for these drivers. The exception to 8.9.1 does not apply.SE5 MarkingSE5.1 A driver that complies with all the applicable requirements of this Supplement may be marked“Class P”.SE5.2 A driver marked “Class P” shall also be marked “F
34、or Connections Use Wire Rated for at Least 90C(194F)” or equivalent.RATIONALE FOR DECISION:This proposal describes the requirements for LED drivers that are inherently or integrally protected fromoverheating when installed as intended for use in luminaires or as part of lighting systems. This protec
35、tionis intended to be analogous to that of Class P ballasts in fluorescent luminaires. As such, Class P driversare expected to:STANDARD NUMBER: UL 8750 -6-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL1. Have an integral fire and electrical
36、enclosure;2. Be suitable for both factory and field wiring;3. Operate within their normal electrical and thermal parameters in their intended operatingenvironment;4. Have thermal management functions independent of the end-product;5. Reliably shut down or reduce their thermal footprint during abnorm
37、al ambient temperatureconditions; and6. Not present a risk of fire or electric shock in the event of an internal component failure.This proposal is not intended to address heat load when the LED driver is integrated into luminaires northe performance and reliability of other luminaire components, su
38、ch as the LED array.The Class P designation was first established for fluorescent lamp ballasts under the Standard forFluorescent-Lamp Ballasts, UL 935. Part of the technical basis for the limited end-product test programrequired of Class P ballasts was the existence of standardized lamp loads. Almo
39、st all of the fluorescentlamps in widespread use in North America have their electrical characteristics defined by ANSI lampstandards. This level of standardization does not yet exist for LED arrays and modules. However, theconstruction and performance requirements in this proposal endeavor to estab
40、lish that Class P LEDdrivers do not present an electrical or thermal hazard of their own when installed in accordance with theirratings and when subjected to either internally or externally-generated foreseeable abnormal conditions.This proposal requires Class P drivers to comply with the UL 8750 co
41、nstruction requirements applicableto stand-alone, hard-wired devices. Compliance is determined independent of any luminaire enclosuresor thermal management methods potentially offered by an end-product design. Driver enclosuretemperatures during normal use are limited to 90C to allow for the pre-sel
42、ection of the end-productsinternal wiring and other insulating materials, and to allow the driver case to be in direct contact withbuilding surfaces and insulation as allowed by the luminaire or lighting system requirements. Theseconstruction requirements are broadly in-line with what is currently r
43、equired of Class P ballasts.This proposal will also require drivers comply with the UL 8750 performance requirements relevant to LEDdrivers with integral fire and electrical enclosures. Recognizing the use conditions with which Class P LEDdrivers are expected to endure, a series of new or revised ab
44、normal condition tests are proposed: Component Failure Test Each component fault is required to be conducted in the driversintended ambient temperature if the end-result of the fault does not manifest itself within 30minutes. Also, faults are not limited to circuits with at least 50 watts of availab
45、le power,recognizing that a fault in a control circuit can result in a potentially hazardous conditionelsewhere in the device. Output Loading Test The test and test criteria currently in the standard are the same,however the LED driver case temperatures shall additionally remain within established C
46、lass Plimits during any type of abnormal output circuit loading. This is intended to address overloadingcaused by abnormal conditions such as circuit faults in the illumination (LED) array, output loadmismatches, damaged or shorted output wiring during installation or replacement, etc.STANDARD NUMBE
47、R: UL 8750 -7-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL Increased-Ambient Temperature Test This new test is intended to determine if a driver canrespond acceptably in the event of externally-generated abnormal ambient temperatures. Thes
48、esituations are known to occur when drivers are installed in luminaire designs or installations thatare thermally unsuitable for the drivers intended operational parameters, such as wheninstalled:1. In recessed wall or ceiling cavities in very warm geographical locations;2. Too close to other heat-g
49、enerating equipment, either within or external to the end-product; or3. In luminaires that are subsequently covered by excessive building insulation.Due to the potential fire risk of this abnormal condition, any protective component or circuit intended todetect and resolve this condition needs to be reliable over time. This protective function is considered tobe reliable if it has built-in redundancy or a suitable supervisory capability. The intent is to avoid disablingthe protection by the failure of any single unreli
