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): WMUZStandard Number: UL 20Standard Title: Standard for General-Use Snap SwitchesEdition Date: May 10, 2010Edition Number: 13Section / Paragraph Reference: Ne
3、w Supplement SASubject: AC Only Flush Switch with Integral Power Supply with Class 2 OutputConnectorsDECISION:SUPPLEMENT SA AC ONLY FLUSH SWITCH WITH INTERGAL POWER SUPPLY WITH CLASS 2OUTPUT CONNECTORSINTRODUCTIONSA1 ScopeSA1.1 The requirements of this supplement cover an AC Only flush switch with i
4、ntegral power supply withone or more Class 2 output low-voltage connectors, intended to be installed in an outlet box.SA1.2 These requirements are applicable to an AC only flush-type switch rated 120 V AC only.SA1.3 An AC Only flush switch with integral power supply with one or more Class 2 output l
5、ow-voltageconnectors is intended only for flush installation in an appropriate enclosure suitable for the application.SA1.4 An AC Only flush switch with integral power supply with one or more Class 2 output low-voltageconnectors shall comply with the applicable requirements of this standard, UL 20,
6、except as modified bythe requirements in this supplement.SA1.5 This supplement does not apply to the enclosure or any part, which forms the enclosure, includingthe outlet box, flush device cover plate or both.SA1.6 This supplement only applies to an AC Only Flush switch with an integral power supply
7、 with Class2 output low voltage connectors. It does not apply to a flush switch and separable Class 2 power supplyor where the Class 2 power supply is either located or derived outside the outlet box.SA2 GlossarySA2.1 For the purpose of this supplement, the following definitions apply.SA2.2 AC ONLY
8、FLUSH SWITCH WITH INTEGRAL POWER SUPPLY WITH ONE OR MORE CLASS 2OUTPUT LOW-VOLTAGE CONNECTORS An AC Only Flush Switch, with an integral power supply andassociated Class 2 output low voltage connectors intended for flush mounting in or on an outlet box forfixed installation on a branch circuit.Constr
9、uctionUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULSA3 GeneralSA3.1 In addition to the construction, performance and marking requirements contained in this standard,an AC Only flush switch with integral power supply with one or more Class 2
10、 output low-voltageconnectors shall also comply with the applicable requirements of UL 1310, the Standard for Class 2 PowerUnits.SA3.2 An AC Only flush switch with integral power supply with one or more Class 2 output low-voltageconnectors shall be provided with a suitable flush device cover plate o
11、r outlet box cover that complies withthe applicable requirements of the Standard for Cover Plates for Flush-Mounted Wiring Devices, UL 514D.Exception: An AC Only flush switch with integral power supply with one or more Class 2 outputlow-voltage connectors need not be provided with a cover plate or b
12、ox cover if all the following conditionsare met:a) The device is intended for use with a cover plate having dimensions that comply with WiringDevices - Dimensional Specifications, ANSI/NEMA WD6 for features intended to accommodatea flush-mounted wiring device of the dimensions specified in ANSI/NEMA
13、 WD6; andb) Markings specified in SA12.1 are visible after installation using a cover plate havingdimensions specified in (a); andc) No cover plate modifications are needed in order to comply with this Standard.SA3.3 The Class 2 low-voltage output connectors of an AC Only flush switch with integral
14、power supplyshall be insulated and extend beyond the plane of the receptacle mounting yoke.SA3.4 The Class 2 low-voltage power supply shall be configured for supply from a single branch circuit.SA4 Polymeric EnclosureSA4.1 In addition to the insulating material requirements of UL 20, Section 4.7, a
15、polymeric material usedto enclose the Class 2 power supply circuitry shall have a flame rating not less than 5V, or comply withthe 127 mm Flame Test specified in UL 746C (Polymeric Material - Use in Electrical EquipmentEvaluations).SA5 SpacingsSA5.1 In addition to the spacing requirements of UL 20,
16、Section 4.9, an AC Only flush switch with integralpower supply with one or more Class 2 output low-voltage connectors, shall also comply with the spacingsrequirements for the power supply circuitry of UL 1310, the Standard for Class 2 Power Units.SA5.2 An AC Only flush switch with integral power sup
17、ply with one or more Class 2 output low-voltageconnectors shall maintain a minimum of a 1/4 inch (6.35 mm) separation of branch circuit wiring and Class2 connections after installation. Compliance is checked my measurement and if necessary, assembly testas identified in Section SA9.SA5.3 An AC Only
18、flush switch with integral power supply with one or more Class 2 output low-voltageconnectors shall provide adequate spacings clearance of 3/64 inch (1.2 mm) between each terminal andthe metal of a standard outlet box of the minimum size in which it is intended to be installed. Complianceis checked
19、by assembly test as identified in Section SA9.SA6 Terminals and LeadsSTANDARD NUMBER: UL 20 -2-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULSA6.1 An AC Only flush switch with integral power supply with one or more Class 2 output low-voltage
20、connectors, shall be provided with a neutral terminal or lead as described in UL 20, Section 5.5.3 and shallalso be identified as described in UL 20, paragraphs 4.5.3.22 through 4.5.3.25.SA6.2 The neutral terminal or lead as identified in clause SA6.1 shall not be bonded to the groundingterminal or
21、dead-metal.SA6.3 Circuitry shall be arranged such that a grounding connection or conductor will not carry currentunder normal operating conditions.PERFORMANCESA7 Temperature TestSA7.1 A previously untested shall not attain a temperature at any point sufficiently high to constitute a riskof fire, to
22、damage any materials employed in the device, or to exceed the temperature rises specified inTable SA7.1.SA7.2 To determine if the AC Only flush switch with integral power supply with one or more Class 2 outputlow-voltage connectors complies with clause SA7.1, the device shall carry its maximum switc
23、h ratedcurrent and shall simultaneously draw the marked ampere rating through the low voltage outputconnectors either individually or collectively until constant temperatures are attained on the switchterminals or wire leads and identified components in Table SA7.1.SA7.3 The device shall be mounted
24、according to the manufacturers instructions and be tested in anon-metallic outlet box mounted in the test wall according to Figure SA7.1. If the device cannot physicallyfit in a box of 63 mm (2.5 in) depth and 75 mm (3 in) height, it shall be tested in a box identified in themanufacturers installati
25、on instructions. The outlet box shall be centered in the test wall.SA7.4 The temperature limits specified in Table SA7.1 are maximum temperatures. However, tests maybe conducted at any ambient temperature within the range of 10 40C (50 104F). If tested at otherthan 25C (77F), the measured temperatur
26、es are to be normalized to 25C (77F).SA7.5 AC Only flush switch with integral power supply with one or more Class 2 output low-voltageconnectors intended for ambient temperatures rated above 40C (104F) shall be tested in an aircirculating oven at the marked rated temperature 2 C or tested at room te
27、mperatures and normalized tothe rated temperature.SA7.6 Temperature readings shall be obtained by using thermocouples consisting of 28 32 AWG (0.08 0.032 mm2) iron and constantan wires. Measurements shall be made on the terminals outside the switchenclosure but adjacent thereto. If a switch has wire
28、 leads, the measurements shall be made on the copperconductors at the point of entrance of the leads to the switch. A temperature shall be considered to beconstant when three successive readings, taken at 5-minute intervals, indicate no change.SA7.7 A thermocouple used for determining the temperatur
29、e of a coil or winding is to be located on theouter surface of the coil or winding or the coil enclosure.SA7.8 A device is to be tested with a minimum of 1.2 m (4 ft) of wire attached to each field-wiring terminal.The wire shall be single solid copper conductor and sized as follows:a) No. 14 AWG sol
30、id copper conductor for 15 A rated switchb) No. 12 AWG solid copper conductor for 20 A rated switchSTANDARD NUMBER: UL 20 -3-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULSA7.9 The acceptability of temperatures for a component such as a prin
31、ted wiring board, an opticalisolator, a dead-case-mounted semiconductor, and for polymeric materials serving as support of live parts,insulation, or an enclosure are to be determined on the basis of the temperature ratings of thecomponents.SA7.10 The temperature rise of any part that can contact the
32、 field wiring and the field wiring terminals orleads shall not exceed 30C (54F). Any part more than 1/4 inch (6.4 mm) behind the mounting yoke isto be considered a part that can contact field wiring.Exception: The temperature rise may exceed 30C but not more than 50C or 65C provided the deviceis app
33、ropriately marked in accordance with SA12.2, and the conductors for field connection integral to thedevice are rated at least equal to the temperature specified in the marking.Table SA7.1 Maximum acceptable temperature risesMaterials and components C F1. Fuse Clip or Switch Contacts 30 542. Rubber-
34、or thermoplastic-insulated conductors: 35 63internal to devicea, bintended for field connectionse, h3. Surfaces that can be contacted by field wiring conductors in outlet boxh35 634. Field-wiring terminalsc, h30 545. External surfaces subject to contact (metallic and nonmetallic)e65 1176. Insulation
35、 systemsClass 105 insulation systemsThermocouple method 65 117Resistance method 85 153Class 105 insulation systems on single-layer series coil with exposed surfaces eitheruninsulated or enameled, thermocouple method90 162Class 130 insulation systemsThermocouple method 85 153Resistance method 105 189
36、7. Phenolic compositiona125 2258. On the embedding material of a resistor 300 5409. On bare resistor materialThermocouple method 375 67510. Capacitor dd11. Power switching semiconductors ff12. Printed-wiring boards ggaThe limitation on phenolic composition and on rubber and thermoplastic insulation
37、does not apply to compounds that havebeen investigated and found acceptable for a higher temperature.bFor standard insulated conductors other than those mentioned in item 2, reference should be made to the National ElectricalCode, ANSI/NFPA 70, and the maximum temperature rise shall not exceed the m
38、aximum operating temperature specified in theCode for the wire in question minus an assumed ambient (room) temperature of 25C (77F). However, a temperature rise onany conductor shall not exceed 30C (54F) where the conductor may come in contact with other conductors.cThe temperature on a wiring termi
39、nal is measured at the point most likely to be contacted by the insulation of a conductorinstalled as in actual service.dFor a capacitor, the maximum acceptable temperature rise is the marked temperature limit of the capacitor minus an assumedambient temperature of 25C (77F).eAny part more than 1/4
40、inch (6.4 mm) behind the mounting yoke is to be considered a part which can contact field wiring.fThe maximum acceptable temperature rise on the semiconductor is the maximum temperature for the applied powerdissipation recommended by the semiconductor manufacturer minus an assumed ambient of 40C (10
41、4F), at the locationspecified by the semiconductor manufacturer.STANDARD NUMBER: UL 20 -4-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTable SA7.1 Maximum acceptable temperature rises ContinuedMaterials and components C FgThe maximum accept
42、able operating temperature of the printed-wiring board shall not be exceeded based on an assumedambient temperature of 25C (77F).hHigher values permitted in accordance with the Exception to SA7.10 and marked in accordance with SA12.2 and TableSA12.1.This is generated text for figtxt.SA8 Class 2 Outp
43、ut Power SupplySA8.1 All low voltage output connectors shall comply with the Class 2 performance requirements of UL1310.SA8.2 All UL 1310 testing where the device is to be energized from a source of supply, the assembly isto be assembled as intended into a nonmetallic outlet box with a depth as spec
44、ified by the manufacturer.The outlet box shall be mounted in a vertical wall section:a) with a depth of minimum 125% of the box depth;b) with plywood or gypsum wallboard surfaces; andc) loosely filled with fiberglass or equivalent thermal insulation.Fig SA7.1Temperature test setupNotes 1. The dimens
45、ions in the figure represent standard building material dimensions and are minimum requirements (i.e. 2x4 wood frameis a plane 1.5 x 3.5 in).2. The insulation shall completely fill the wall cavitySTANDARD NUMBER: UL 20 -5-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION
46、 WITHOUT PERMISSION FROM ULSA8.3 Under any condition of low voltage output loading, individually or collectively, tests shall beconducted to represent the worst case of (a) no load on the branch circuit switch, and (b) full load fromthe branch circuit switch.SA8.4 Temperature testing of SA7 may be p
47、erformed under the UL 1310 temperature testing, providedthe maximum acceptable temperature rise of individual components in Table SA7.1 are met and if,agreeable to all parties.SA9 Assembly TestSA9.1 An AC Only flush switch with integral power supply with one or more Class 2 output low-voltageconnect
48、ors with integral power supply with one or more Class 2 output low-voltage connectors shall:a) maintain a minimum of a 1/4 inch (6.35 mm) separation of branch circuit wiring and Class 2connections, andb) maintain adequate spacings clearance between each terminal and the metal of a standardoutlet box
49、 of the minimum size in which it is intended to be installed, andc) shall not permit contact to be made between the probe shown in UL 20, Figure 2 and anylive part through the Class 2 output connectors or through any flush device cover plate or outletbox cover opening or joint surrounding the installed device.SA9.2 An AC only flush switch with integral power supply with one or more Class 2 output low-voltageconnectors shall be wired with the largest conductor (AWG) size when installed into the minimum sizemetallic outlet box, as indicated in th
