1、Subject 296A 12 Laboratory Drive Research Triangle Park, NC 27709 October 18, 2000 TO: Industry Advisory Conference of UL for Residential Type Oil-Burning Appliances, Electrical Council of Underwriters Laboratories Inc., Fire Council of Underwriters Laboratories Inc., Subscribers to ULs Standards Se
2、rvice for Waste Oil-Burning Air-Heating Appliances SUBJECT: Request for Comments on Proposed Requirements for the Second Edition of the Standard for Waste Oil-Burning Air-Heating Appliances, UL 296A; PROPOSED EFFECTIVE DATE SUMMARY OF TOPICS This bulletin proposes the following changes in requiremen
3、ts: Motor terminal housing minimum dimension specifications Revisions to conduit size Minimum amperage rating of leads and terminals Additional wire types available for use Exceptions to circuit separation requirements The grounding symbol as an additional marking option Additional marking requireme
4、nts for Class 2 and Class 3 circuits Editorial revision COMMENTS DUE: November 29,2000 Attached as Appendix A for your review and comment are proposed requirements for UL 296A. Questions regarding interpretation of requirements should be directed to the responsible UL Staff. Please see Appendix B of
5、 this bulletin regarding designated responsibility for the subject product category. Please note that proposed requirements are of a tentative and early nature and are for review and comment only. Current requirements are to be used to judge a product until these requirements are published in final
6、form. SUBJECT 296A -2- OCTOBER 18,2000 PRODUCTS AND INDUSTRIES AFFECTED BY THE PROPOSAL UL requests your assistance in identifying other products or industries that might be affected by the requirements contained in this bulletin. UL suggests that all suppliers or customers for these products and in
7、dustries be made aware of these requirements prior to their proposed effective date. Also, please forward your suggestions to UL so that these products and industries may be identified in future bulletins. PROPOSED EFFECTIVE DATES The proposed requirements specified in the following table will neces
8、sitate a review of currently Listed products. Therefore, UL proposes that the new requirements become effective 18 months after publication. This is intended to provide manufacturers with sufficient time to acknowledge the modification of products and to implement the necessary changes in production
9、. Please note that this also includes the time that will be needed by UL to conduct a review of the modified product. Item Number I Topic I Reference Number I Proposed Effective Date 1 I Motor Terminal Housing 16.1.4 and 2. Your comments concerning the proposed effective dates, should the proposals
10、be adopted. Comments should be made in writing and may be sent by email, fax, or mail to the attention of Tim Lupo at ULs Research Triangle Park office, 12 Laboratory Drive, Research Triangle Park, NC 27709-3995. Please reference all correspondence to Subject 296A. All comments should be sent by Nov
11、ember 29, 2000. Unless specifically requested to do so, UL will not acknowledge comments indicating concurrence with these proposals. SUBJECT 296A OCTOBER 18,2000 UNDERWRITERS LABORATORIES INC. TIM LUPO Associate Project Engineer Standards Department RESEARCH TRIANGLE PARK OFFICE Fax: (919) 547-6480
12、 Email: timothy.e.lupoQ (919) 549-1491 SR:JAH REVIEWED BY: T.K. THOMPSON Staff Engineering Associate Conformity Assessment Services 301 5BRTP RESEARCH TRIANGLE PARK OFFICE (91 9) 549-1 955 bul-296a.2-20000502 SUBJECT 296A -Al - OCTOBER 18,2000 APPENDIX A PROPOSED REQUIREMENTS AND PROPOSED EFFECTIVE
13、 DATES FOR THE SECOND EDITION OF THE STANDARD FOR WASTE OIL-BURNING AIR-HEATING APPLIANCES, UL 296A For your convenience in review, proposed additions to existing requirements are shown underlined and proposed deletions are shown thed-e and b) From uninsulated live parts connected to different circu
14、its or opposite-polarity parts of the same circuit. Exception No. 1: This reauirement does not awlv to conductors in enclosures where electric liaht, Dower, and Class 1 conductors are introduced solelv to connect the eaubment to Class 2 or Class 3 circuits where the electric liaht, Dower, or Class 1
15、 circuit conductors are routed to maintain at least 1/4 inch soacina to the Class 2 and Class 3 circuit conductors. SUBJECT 296A -A6- OCTOBER 18,2000 Exception No. 2: This reauirement does not awlv when the electric liaht, Dower, or Class 1 circuit operates at 150 volts or less. the around and to Cl
16、ass 2 and Class 3 circuits are installed usina TvDes CL3. CL3. or CL3P wirina materials. and the conductor lenath extendina bevond the insulation of the wirina material is spaced at least 1/4 inch from all other conductors. 9.1 revised (date of publication) 6. GROUNDING SYMBOL RATIONALE UL proposes
17、to allow the use of the IEC grounding symbol to identify equipment-grounding terminals. This symbol has become familiar globally, and meets the intent of the current requirements. This addition corresponds with Section 250-1 19 of the National Electrical Code, ANSVNFPA-70. UL proposes these revision
18、s become effective upon publication. IMPACT Adoption of this proposal would not require a review of presently Listed heating equipment as manufacturers would be provided with the option of using the IEC grounding symbol to identify equipment-grounding terminals. PROPOSALS 10.18 A wire-binding screw
19、intended for the connection of an equipment grounding conductor shall have a green colored head that is hexagonal-shaped, slotted, or both. A pressure wire connector intended for the connection of an equipment grounding conductor shall be identified by being marked ”G”, ”GR”, ”GROUND”, or ”GROUNDING
20、”, or with the aroundina svmbol illustrated in Fiaure 10.1 or by a marking on a wiring diagram provided on the equipment. The wire-binding screw or pressure wire connector shall be secured to the frame or enclosure and shall be located so that it will not need to be removed during servicing. For a w
21、ire-binding screw, upturned lugs or the equivalent shall be provided to retain the conductor. tf When a pressure wire connector is used adjacent to the connectors intended for the supply conductors involving the neutral of a grounded supply, a marking shall be additionally provided indicating ”EQUIP
22、MENT GROUND” or the connector shall be identified by a green color or by both the specified wording and a green color. 10.18 revised (date of publication) SUBJECT 296A -A7- OCTOBER 18,2000 Figure 10.1 Symbol for equipment grounding conductor Figure 10.1 added (date of publication) 7. CLASS 2 AND CLA
23、SS 3 CIRCUIT MARKING RATIONALE UL proposes to add paragraph 34.1 1 to reflect the intent of the requirement. The proposal would specify conditions under which additional marking would be required. These revisions correspond with Section 725-41 and Tables 11 A and 11 B of the National Electrical Code
24、. UL proposes these revisions become effective 18 months after publication. IMPACT Adoption of this proposal would require a review of presently Listed heating equipment to determine compliance with the new marking requirements. Therefore, UL proposes that the revision become effective 18 months aft
25、er publication. PROPOSAL 34.1 1 Class 2 and Class 3 power circuits shall be marked to identify the circuit as a Class 2 or Class 3 circuit as applicable, and to specify the circuits electrical rating. In addition, a Class 2 circuit not suitable for wet locations shall be so marked. Added 34.1 1 effe
26、ctive (18 months after date of publication) SUBJECT 296A -A8- 8. EDITORIAL CHANGES OCTOBER 18,2000 RATIONALE UL proposes to clarify several paragraphs to reflect the intent of the requirements. These proposals are editorial in nature. UL proposes these revisions become effective upon publication. IM
27、PACT As these proposals are strictly editorial in nature, a review of currently Listed products would not be necessary if they were adopted. PROPOSAL 22.3 #When other chemical elements are present in the test fuel, WS cc- they or 2) Lead - 400 ppm minimum; b) Aluminum - 10 to 20 ppm; c) Copper - 20
28、to 50 ppm; d) Magnesium - 200 ppm minimum; e) Calcium - 100 ppm minimum; f) Phosphorus - 800 ppm maximum; g) Boron - 10 to 40 ppm; h) Sodium - 100 to 250 ppm; i) Nickel - 3 ppm minimum; j) Chromium - 3 ppm minimum; k) Silicone - 10 to 50 ppm; and I) Zinc - 400 ppm. 22.3 revised (date of publication)
29、 SUBJECT 296A -Ag- OCTOBER 18,2000 87.6.1 The cold-air inlet and warm-air outlet openings of the furnace are to be extended beyond the test enclosure by an appropriate duct or ducts. A metal plenum chamber having the same dimensions as the discharge opening of the furnace is to be provided by the ma
30、nufacturer for test purposes. The plenum and the warm-air duct are to be constructed as indicated in Figure 87.7. The inlet-air duct is to have the same dimensions as the inlet opening of the furnace. The ducts are to extend at least 12 inches f35mmj /300 beyond the walls of the test enclosure. 87.6
31、.1 revised (date of publication) 87.6.2 A thermocouple grid, as shown in Figure 87.7, is to be located in the warm-air duct in a plane within 6 inches fE+mmj /150 mml downstream from the position closest to the plenum where any thermocouple will be in line-of-sight of any surface of the heat exchang
32、er. The duct is to extend at least 6 inches 4150 mmlbeyond the thermocouple grid. 87.6.2 revised (date of publication) Table 11 1.1 Corrosion protection Table 11 1.1 revised (date of publication) Type of cabinet and enclosure Outer cabinets that protect motors, wiring, or enclosed current-carrying p
33、arts Inside enclosures that protect current- carrying parts other than motors Outer cabinets that are the sole enclosure of current-carrvinq parts For uncoated sheet metal 0.053 inch (1.35 mm) thick and greater or for metal coated sheet metal 0.056 inch (1.42 mm) thick and greater as specified in pa
34、ragraph M4A- 11 1.2.4 M4A- 11 1.2.4 +HA+ 11 1.2.4 For uncoated sheet metal less than 0.053 inch thick or for metal coated sheet metal less than 0.056 inch thick as specified in paragraph +HA+ 11 1.2.5 +HA+ 11 1.2.5 +HA+ 11 1.2.5 OC 019 35 i631 35 i631 50 i901 50 i901 65 11 171 65 11 171 65 11 171 80
35、 11 441 Table 11 7.2 Accelerated aging test criteria Table 117.2 revised (date of publication) Measured temperature rise dearees Material Rubber or neoprene Thermoplastic Rubber or neoprene Thermoplastic Rubber, neoprene or thermoplastic Rubber or neoprene Thermoplastic Rubber, neoprene or thermopla
36、stic Test Program Air oven aging for 70 hours at :CU% (212F) 100 f2“C (212 f3.6“F) 7 days in an air-circulating oven at 87C (1 89F) Air oven aging for 168 hours at $88“ (W) 100 f2“C (212 f3.6“F) 10 days in an air-circulating oven at $88“ (W) 100 f2“C (212 f3.6“F) 7 days in an air-circulating oven at
37、 113C (235F) 10 days in an air-circulating oven at 121C (250F) 7 days at 121 “C or 60 days at 97C (207F) in an air-circulating oven 7 days in an air-circulating oven at 136C (277F) SUBJECT 296A CCN LUQH -B1- Off ice/Subsidiary I Responsible Engineer I Extension Melville Robert Wozniak 22454 OCTOBER
38、18,2000 APPENDIX B DESIGNATED RESPONSIBILITY FOR UL PRODUCT CATEGORY LUQH, WASTE OIL BURNING APPLIANCES The individuals shown in the following tables are involved with the investigation of products covered under the subject category. The Primary Designated Engineer (shown in UPPERCASE letters) coord
39、inates the establishment and uniform interpretation of UL requirements applicable to the product category. The Designated Engineers (shown in lowercase letters) work with the Primary Designated Engineer to interpret requirements and maintain standards. Should you have questions regarding the interpr
40、etation of the requirements proposed in this bulletin or any adopted requirements that affect your product, you are encouraged to contact the individual at the office to which you normally submit your products. The Managing Engineer for the subject category is Don Grob at ULs Northbrook office. The
41、Managing Engineer oversees the significant interpretations made by the Primary Designated Engineer and arbitrates any differences regarding interpretation of UL requirements. I I I Northbrook John Pallanti 4291 3 I RTP I T.K. THOMPSON I 11 955 Santa Clara David Jordan 32743 SUBJECT 296A -B2- No Text on This Page OCTOBER 18,2000
