1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 2788 Industrial and Commercial VibratorsUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR F
2、URTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Industrial and Commercial Vibrators, UL 2788 First Edition, Dated June 6, 2014 Summary of Topics This is the First Edition of ANSI/UL 2788. The new requirements are substantially in accordance with Proposal(s)
3、on this subject dated February 21, 2014. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form by any means, electronic, mechanical photocopying, recording, or otherwise without prior permission of UL. UL provides this Standard a
4、s is without warranty of any kind, either expressed or implied, including but not limited to, the implied warranties of merchantability or tness for any purpose. In no event will UL be liable for any special, incidental, consequential, indirect or similar damages, including loss of prots, lost savin
5、gs, loss of data, or any other damages arising out of the use of or the inability to use this Standard, even if UL or an authorized UL representative has been advised of the possibility of such damage. In no event shall ULs liability for any damage ever exceed the price paid for this Standard, regar
6、dless of the form of the claim. Users of the electronic versions of ULs Standards for Safety agree to defend, indemnify, and hold UL harmless from and against any loss, expense, liability, damage, claim, or judgment (including reasonable attorneys fees) resulting from any error or deviation introduc
7、ed while purchaser is storing an electronic Standard on the purchasers computer system. The requirements in this Standard are now in effect, except for those paragraphs, sections, tables, gures, and/or other elements of the Standard having future effective dates as indicated in the note following th
8、e affected item. The prior text for requirements that have been revised and that have a future effective date are located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice. JUNE 6, 2014 UL 2788 tr1UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION
9、WITHOUT PERMISSION FROM UL JUNE 6, 2014 UL 2788 tr2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JUNE 6, 2014 1 UL 2788 Standard for Industrial and Commercial Vibrators First Edition June 6, 2014 This ANSI/UL Standard
10、for Safety consists of the First Edition. The most recent designation of ANSI/UL 2788 as an American National Standard (ANSI) occurred on June 4, 2014. ANSI approval for a standard does not include the Cover Page, Transmittal Pages, Title Page, or effective date information. Comments or proposals fo
11、r revisions on any part of the Standard may be submitted to UL at any time. Proposals should be submitted via a Proposal Request in ULs On-Line Collaborative Standards Development System (CSDS) at http:/. ULs Standards for Safety are copyrighted by UL. Neither a printed nor electronic copy of a Stan
12、dard should be altered in any way. All of ULs Standards and all copyrights, ownerships, and rights regarding those Standards shall remain the sole and exclusive property of UL. COPYRIGHT 2014 UNDERWRITERS LABORATORIES INC. ANSI/UL 2788-2014UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCT
13、ION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - UL 2788 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CONTENTS INTRODUCTION 1 Scope .5 2 Components 6 3 Units of Measur
14、ement .6 4 Undated References 6 5 Glossary .6 CONSTRUCTION 6 Vibrators Provided With Controls .8 7 Motor Protection 8 8 Mechanical Assembly .9 9 Frame and Enclosure 10 9.1 General 10 9.2 Cast metal enclosures .11 9.3 Sheet metal enclosures 11 9.4 Polymeric enclosures 13 10 Grounding .14 11 Grounding
15、 Identication .15 12 Ventilation Openings 16 12.1 General .16 12.2 Barriers used with ventilation openings 17 13 Accessibility of Uninsulated Live Parts, Film-Coated Wire, and Moving Parts 19 14 Protection Against Corrosion .24 15 Cord-Connected Vibrators .26 16 Input and Output Connections 28 17 Fa
16、ctory Wiring Terminals and Leads 34 18 Spacings 35 19 Current-Carrying Parts 38 20 Internal Wiring 38 21 Bonding for Grounding 40 21.1 Bonding conductor .40 21.2 Bonding and grounding connections 41 22 Electrical Insulation .41 PERFORMANCE 23 General 43 24 Input Test 44 25 Temperature Test .44 26 Le
17、akage Current Test .48 27 Mechanical Tests .51 27.1 General .51 27.2 Pressure test 52 27.3 Impact test 52 27.4 Mold stress relief .52 27.5 Conduit hubs 53 27.6 Rain test 53 27.7 Lifting lugs 57 JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - UL 2788 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FUR
18、THER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 28 Strain Relief Test .57 28.1 Power supply cord 57 28.2 Interconnecting leads .57 29 Push-Back Relief Test 57 30 Dielectric Voltage-Withstand Test .58 31 Limited Short Circuit Test .58 32 Grounding Test .60 MANUFACTURING AND PRODUCTION TE
19、STS 33 Production-Line Dielectric Voltage-Withstand Test 60 MARKINGS 34 General 62 35 Legibility and Permanence .63 36 Environmental Related Markings 63 INSTRUCTIONS 37 General 64 JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - UL 2788 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCT
20、ION OR DISTRIBUTION WITHOUT PERMISSION FROM UL INTRODUCTION 1 Scope 1.1 These requirements cover industrial and commercial vibrators designed and intended to facilitate the ow and settling of granular materials and slurries. 1.2 These products are intended to be mounted to bins, chutes, hoppers, tab
21、les, forms, and/or vehicle beds or containers. 1.3 The products covered by these requirements are electrically operated, AC and/or DC and are rated 1,000 volts single or three-phase or less. 1.4 These requirements do not cover products intended for use with ammable or combustible liquids. 1.5 These
22、requirements do not cover products intended for use in hazardous locations as dened in the National Electrical Code, NFPA 70. The National Electrical Code and NEC are registered trademarks of the National Fire Protection Association, Inc., Quincy, MA 02169 1.6 If the risk of re does not exist at a v
23、ibrator, part, or circuit, then the requirements of this Standard intended to address the risk of re shall not apply to that vibrator, part, or circuit. 1.7 If the risk of electric shock does not exist at a vibrator, part, or circuit, then the requirements of this Standard intended to address the ri
24、sk of electric shock shall not apply to that vibrator, part, or circuit. 1.8 The requirements of this Standard intended to address the risk of re do not apply to a product provided with a metal enclosure in which there are no openings in the enclosure through which molten metal, burning insulation,
25、aming particles, or other ignited material could fall onto ammable material, or through which a ame could be projected. 1.9 The products covered by these requirements have not been evaluated for the sound pressure levels produced during operation. JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - U
26、L 2788 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 2 Components 2.1 Except as indicated in 2.2, a component of a product covered by this Standard shall comply with the requirements for that component. 2.2 A component is not required to
27、comply with a specic requirement that: a) Involves a feature or characteristic not required in the application of the component in the product covered by this Standard; or b) Is superseded by a requirement in this Standard. 2.3 A component shall be used in accordance with its rating established for
28、the intended conditions of use. 3 Units of Measurement 3.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory or approximate information. 4 Undated References 4.1 Any undated reference to a code or standard appearing in the requirements of this standard shal
29、l be interpreted as referring to the latest edition of that code or standard. 5 Glossary 5.1 For the purposes of this Standard, the following denitions apply. 5.2 CORD CONNECTED VIBRATOR A vibrator that is intended to be connected to a source of supply in the eld by means of a exible cord and an att
30、achment plug that are both provided with the motor. 5.3 ENCLOSURE That portion of a unit that: a) Reduces the accessibility of a part that involves a risk of re, electric shock, or injury to persons; or b) Reduces the risk of propagation of ame, sparks, and molten metal initiated by an electrical di
31、sturbance occurring within. 5.4 DIRECTLY ACCESSIBLE VIBRATOR A vibrator that can be physically contacted without opening or removing any part, or is located so that it is accessible to contact. 5.5 FACTORY INSTALLATION The act of wiring and mounting a vibrator in a manufacturing environment under co
32、ntrolled conditions by trained personnel. 5.6 FIELD INSTALLATION The act of wiring and mounting a vibrator outside of a manufacturing environment where the installation is subject to the requirements of the National Electrical Code, NFPA 70. 5.7 FIELD TERMINAL COMPARTMENT Where the outgoing power is
33、 connected to the vibrator at the eld installation site and the connection is a wire-to-terminal connection. JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - UL 2788 6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 5.8 FIELD WIRING COMPART
34、MENT Where the outgoing power is connected to the vibrator at the eld installation site and the connection is a wire-to-wire connection. 5.9 FIXED EQUIPMENT Equipment that is intended to be permanently connected electrically to the wiring system. 5.10 GROUND A conducting connection, whether intentio
35、nal or accidental, between an electrical circuit or equipment and the earth or to some conducting body that serves in place of the earth. 5.11 GROUNDING CONDUCTOR An equipment or circuit conductor that is intentionally connected between that electrical circuit or equipment and the earth or to some c
36、onducting body that serves in place of the earth. 5.12 INDIRECTLY ACCESSIBLE VIBRATOR A vibrator that is accessible only by opening or removing a part of the outer enclosure, such as a guard or panel, that can be opened or removed without the aid of a tool, or is located at such a height or is other
37、wise guarded or enclosed so that it is unlikely to be contacted. 5.13 INTERMITTENT DUTY VIBRATOR A vibrator that is intended to operate for no longer than a specied time period or for a specied duty-cycle. 5.14 PERMANENTLY CONNECTED Connected to branch circuit wiring by a means other than a exible c
38、ord and attachment plug, such as by using conduit. 5.15 PERMANENTLY INSTALLED Secured to a mounting surface by a means that requires the use of a tool for removal. 5.16 PORTABLE A product that is easily carried or conveyed by hand, and is provided with a power- supply cord for connection to the supp
39、ly circuit. 5.17 PROTECTIVE IMPEDANCE An impedance connected between live parts and accessible metal parts, and of such a value that the current is limited to a safe value. 5.18 RISK OF ELECTRIC SHOCK A risk of electric shock is considered to exist at any part if: a) The potential between the part a
40、nd earth ground or any other simultaneously accessible part is more than 42.4 V peak for alternating current potentials or 60 volts for direct current potentials; and b) The continuous current ow through a 1500-ohm resistor connected across the potential exceeds 0.5 mA. 5.19 RISK OF FIRE A risk of r
41、e is considered to exist if the open-circuit voltage between any two points is equal to or greater than 2500 volts peak, or if power of more than 15 watts can be delivered into an external resistor connected between the two points. 5.20 SIMULTANEOUSLY ACCESSIBLE Parts are considered to be simultaneo
42、usly accessible when they are no further than 2 m (6.6 feet) apart. 5.21 SHEET METAL SCREW A screw with a thread pitch that exceeds the thickness of the sheet metal and is designed to engage an unextruded, unthreaded hole in the metal. JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - UL 2788 7UL C
43、OPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 5.22 SMALL PARTS Materials that do not exceed 2 cm 3 (0.12 in 3 ) in volume and 3 cm (1.18 in) in maximum dimension, and are located such that they cannot propagate ame from one area to another or
44、act as a bridge between a possible source of ignition and other ignitable parts. 5.23 STATIONARY Equipment that is intended to be fastened in place or located in a dedicated space, and is provided with a power-supply cord for connection to the supply circuit. CONSTRUCTION 6 Vibrators Provided With C
45、ontrols 6.1 When a vibrator is provided with an electronic control or where an electronic control provides required protection, the control shall comply with the Standard for Industrial Control Equipment, UL 508, or the Standard for Power Conversion Equipment, UL 508C. 7 Motor Protection 7.1 Motor o
46、ver-temperature protection shall be provided for the motor of a vibrator by one of the following: a) Compliance with the requirements contained in the Standard for Impedance Protected Motors, UL 1004-2; b) Compliance with the requirements contained in the Standard for Thermally Protected Motors, UL
47、1004-3; c) Compliance with the requirements contained in the Standard for Electronically Protected Motors, UL 1004-7; or d) A separate device responsive to motor current and rated and set to trip at not more than the percentage of the motor nameplate full-load current rating specied in Table 7.1. If
48、 the percentage protection specied in Column A of Table 7.1 does not correspond to the percentage value of an overload relay of a standard size, the device of the next higher size may be used. However, the overload device of the next higher size shall protect against currents exceeding the percentag
49、e values specied in Column B of Table 7.1. Exception: A vibrator that is intended to be permanently connected or permanently installed and is marked in accordance with 34.7, is not required to comply with this requirement. JUNE 6, 2014 INDUSTRIAL AND COMMERCIAL VIBRATORS - UL 2788 8UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Table 7.1 Protective device activation level Motor Maximum percent of full-
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