1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJune 6, 20081SUBJECT 1801OUTLINE OF INVESTIGATIONFORPOWER DISTRIBUTION CENTERS FOR COMMUNICATIONS EQUIPMENTIssue Number: 3June 6, 2008Summary of TopicsThis new issue of Outline of Investigation,
2、Subject 1801 revises referencesto IEC 61204-7 to reflect that it is no longer a draft document.The UL Foreword is no longer located within the UL Standard. For informationconcerning the use and application of the requirements contained in thisStandard, the current version of the UL Foreword is locat
3、ed onULStandardsInfoNet at: http:/ 2008 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJUNE 6, 2008SUBJECT 18012No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION W
4、ITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 General 41.1 Scope .41.2 Definitions .61.7 Markings and instructions 72 Protection from hazards .73 Wiring, connections, and supply .104 Physical requirements 105 Electrical requirements and simulated abnormal conditions .10JUNE 6, 2008 SUBJECT 1801 3UL
5、 COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 General1.1 Scope1.1.0 Addition of text to 1.1:The requirements in this Outline are to be used as a supplement to the requirements located within IEC61204-7: Low Voltage Power Supplies
6、, D.C. Output Part 7, Annex PS-E.Referenced within IEC 61204-7 is the third edition of the Standard for Safety of Information TechnologyEquipment, UL 60950/CSA C22.2 No. 60950-00. Therefore, the numbering scheme of the clauses andsubclauses located in this Outline correspond to those found in UL 609
7、50/CSA C22.2 No. 60950-00. Therequirements of UL 60950/CSA C22.2 No. 60950-00 are applicable with the exceptions noted in theOutline as replacements, additions, and deletions.The requirements from IEC 61204-7: Low Voltage Power Supplies, D.C. Output Part 7, Annex PS-E,shall apply where details are n
8、ot specifically provided in this Outline.Where a particular subclause of IEC 61204-7 and UL 60950/CSA C22.2 No. 60950-00 is not mentionedin this outline, that subclause shall apply. The relevant requirement, test specification, or note in UL60950/CSA C22.2 No. 60950-00 should be adapted accordingly
9、where this Outline states addition,modification, or replacement,.The block diagram in Figure 1A displays, in single line form, a typical d.c. power distribution system. Therectifiers provide the power for the telecommunications load equipment and maintain the charge (float) inthe batteries. The batt
10、eries and/or the backup generator provide the energy when interruption ofcommercial a.c. power occurs. The d.c. distribution system is to provide energy to the telecommunicationsload equipment with minimal power losses regardless of the state of commercial a.c. power. The d.c.power distribution syst
11、em transmits the energy from the rectifiers or batteries to the telecommunicationsload equipment. Overcurrent protection devices may be provided within the distribution among the rectifieroutputs, batteries, or the input to the primary distribution system. The rigid bus bar, which is typically used,
12、is designed for a minimum voltage drop and is a distribution structure capable of withstanding faultcurrents.The distribution system may be divided into the primary and secondary distribution. The primarydistribution system contains the overcurrent protection devices, the wire, and cable to connect
13、the outputvoltage from the batteries and rectifiers to the secondary distribution system. The overcurrent protectiondevices provide the fault and isolation protection when a short or overload condition occurs on the wire orcable between the primary and secondary distribution systems. The secondary d
14、istribution systemcontains the overcurrent protection devices (such as fuses and circuit breakers), the wire, and cable toconnect the output voltage from the rectifiers and the primary distribution system to thetelecommunications load equipment. The overcurrent protection devices in the secondary di
15、stributionsystem are intended to protect the wire and cable from faults in the secondary distribution system.Equipment faults are normally protected by overcurrent protection devices either within thetelecommunications load equipment of the frames, which contain the telecommunications load equipment
16、,or within the D.C. SECONDARY DISTRIBUTION circuit.This is generated text for figtxt.JUNE 6, 2008SUBJECT 18014UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULAddition of Figure:Figure 1ATypical line block diagram of a d.c. power distribution s
17、ystemJUNE 6, 2008 SUBJECT 1801 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL1.1.3.102 ExclusionsAddition:This outline does not apply to the following: power units other than Class 2 covered by the Standard for Power Units Other Than Class
18、2,UL 1012, and General Use Power Supplies, CSA C22.2 No. 107.1; Class 2 power units covered by the Standard for Class 2 Power Units, UL 1310, and PowerSupplies With Extra-Low-Voltage Class 2 Outputs, C22.2 No. 223; Telephone equipment covered by the Standard for Information Technology Equipment Safe
19、ty- Part 1: General Requirements, UL 60950-1, and CSA C22.2 No. 225; and Uninterruptible power supply equipment (d.c. to a.c. inverters) covered by the Standard forUninterruptible Power Systems, UL 1778, and General Use Power Supplies, CSA C22.2 No.107.1.1.2 DefinitionsAddition:The definitions locat
20、ed within IEC 61204-7: Low Voltage Power Supplies, D.C. Output Part 7, AnnexPS-E apply with the following additions:Definitions in alphabetical order of nounsDISTRIBUTION, D.C. BRANCH 1.2.8.101DISTRIBUTION, D.C. PRIMARY 1.2.8.102DISTRIBUTION, D.C. SECONDARY 1.2.8.103SYSTEM, CENTRALIZED D.C. POWER 1.
21、2.12.101TERMINAL, FIELD WIRING 1.2.5.101VOLTAGE, BATTERY FLOAT (OPERATING) 1.2.12.102VOLTAGE, BATTERY EQUALIZE 1.2.12.1031.2.5.101 FIELD WIRING TERMINAL : Any terminal to which a power supply circuit can be connected by aninstaller in the field is a field-wiring terminal unless the wire is pre-conne
22、cted as a part of the product,including the following: a pressure terminal connector, soldering lug, soldered loop, or crimped eyelet.1.2.8.101 D.C. BRANCH DISTRIBUTION : The circuit conductors, external to the equipment, between anovercurrent protective device and the downstream equipment.1.2.8.102
23、 D.C. PRIMARY DISTRIBUTION : All d.c. power circuits from the discharge bus to the input, and fromthe input to the second overcurrent protection devices downstream from the discharge bus (as shown inFigure 1A). The overcurrent protection devices shall be fuses, circuit breakers, or other devices whi
24、chprovide equivalent protection.1.2.8.103 D.C. SECONDARY DISTRIBUTION : Includes all circuits between the D.C. PRIMARY DISTRIBUTION and theload equipment (as shown in Figure 1A). The overcurrent protection devices shall be fuses, circuitbreakers or other devices which provide equivalent protection,
25、and shall be selected to protectconductors.JUNE 6, 2008SUBJECT 18016UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL1.2.12.101 CENTRALIZED D.C. POWER SYSTEM : A d.c. power system (d.c. power plant and distribution)normally consisting of batter
26、ies, charger/rectifier circuits, and primary and secondary distributionequipment intended to provide power to equipment loads.1.2.12.102 BATTERY FLOAT (OPERATING) VOLTAGE : The voltage that is applied by the rectifier circuit to helpmaintain batteries at their full charge. Each battery type has its
27、own characteristic float voltage.1.2.12.103 BATTERY EQUALIZE VOLTAGE : A higher voltage which is occasionally supplied to batteries inorder to bring the individual cells up to their maximum capacity.1.7 Markings and instructions1.7.6 Fuse identificationAddition:The fuse replacement information need
28、not be marked at the factory for d.c. distribution fuses. However,instructions and a means shall be provided for the installer to mark and identify the fuse replacementinformation.2 Protection from hazardsThis clause is applicable, except as follows:2.7 Overcurrent and earth fault protection in prim
29、ary circuits2.7.1 Basic requirementsAddition:An overcurrent protective device shall have a D.C. VOLTAGE rating no less than the maximum voltage of theRATED VOLTAGE RANGE of the equipment.2.7.105 Fuses2.7.105.1 Power FusesA fuse which protects D.C. BRANCH DISTRIBUTION wiring shall comply with the req
30、uirements for operation at themaximum voltage of the RATED VOLTAGE RANGE. The fuse shall comply with one of the following:a) Branch circuit protection requirements in UL 248-1: current-carrying capacity; overload clearing times; clearing at rated d.c. voltage; d.c. interrupting ability; d.c. maximum
31、 energy;NOTE D.C. test circuits may be resistive, thus no time constant is specified.JUNE 6, 2008 SUBJECT 1801 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULb) The fuse shall be rated 30A or less and shall protect the downstream conductors
32、undershort circuit and overload conditions. In addition, wiring protected by the fuse shall be at leastone size larger than the minimum required wire based on the National Electrical Code, NFPA70 ampacity tables; orc) An alarm indicating that a fuse rated 1.66A may be used for 22 AWG wire, 26 AWG wi
33、re,and a single conductor up to 128 pair cable.2.7.105.2 Alarm indicating fusesAn alarm-indicating fuse that employs electrical alarm contacts shall have alarm contacts suitable for theapplication.An alarm-indicating fuse shall be housed in a fuseholder designed to accommodate the fuse.2.7.106 Circu
34、it breakers and supplementary protectorsA circuit breaker or supplementary protector that protects D.C. BRANCH DISTRIBUTION shall comply with therequirements for operation at the maximum voltage of the RATED VOLTAGE RANGE. A circuit breaker orsupplementary protector shall be suitable for operation a
35、t 100 percent of its rated current.A circuit breaker or supplementary protector shall comply with the requirements for Performance in theStandard for Molded-Case Circuit Breakers, Molded-Case Switches and Circuit-Breaker Enclosures, UL489.Exceptions:1) The endurance test may be performed with 1000 l
36、oad operations and zero no-loadoperations; and2) D.C. test circuits may be resistive, thus no time constant is specified.2.9 Electrical insulation2.9.5 Categories of insulationJUNE 6, 2008SUBJECT 18018UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION F
37、ROM ULAddition to table 2G:Table 2GExamples of application of insulationGrade of isolation Insulation Key to Figure 5Abetween: and:2. BASIC ELV or SELV CIRCUITS thatoperate at HAZARDOUSENERGY LEVELS earthed conductive parts oropposite polarity (exceptsense leads and logic circuitswhere abnormal test
38、ingdemonstrates no hazardouscondition exists)B101101Conditions applicable to table 2GAddition:101) Conductors that are protected by overcurrent protection and where short circuit testing can beperformed to verify no hazardous condition exists, can be evaluated to subclauses 2.10.1, 2.10.3, and2.10.4
39、 as OPERATIONAL INSULATION.This is generated text for figtxt.Addition to Figure 2FJUNE 6, 2008 SUBJECT 1801 9UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL3 Wiring, connections, and supply3.4 Disconnection from the a.c. mains supply3.4.1 Gen
40、eral requirementsAddition:In RESTRICTED ACCESS LOCATIONS, a disconnect device need not be provided for D.C. PRIMARY DISTRIBUTION or D.C.SECONDARY DISTRIBUTION except in computer rooms as specified by the National Electrical Code, NFPA 70.3.101 Centralized d.c. power distribution3.101.1 The ampacity
41、of a bus bar, or clamped joint, complies with the requirements if the temperaturerise limits are not exceeded.4 Physical requirements4.5 Thermal requirements4.5.101 D.C. distribution panel temperature testThe temperature values specified shall not be exceeded due to the d.c. distribution panel carry
42、ing ratedcurrent continuously until constant temperatures are attained.The test may be conducted at any voltage resulting in rated current flow.Equipment shall be tested under the most adverse actual or simulated conditions permitted in themanufacturers installation instructions.A d.c. distribution
43、panel is to be loaded to rated value by distributing the load among the distribution unitsat 100 percent of their ratings unless otherwise specified in the installation instructions.5 Electrical requirements and simulated abnormal conditions5.3 Abnormal operating and fault conditions5.3.6 Simulation
44、 of faultsAddition to 5.3.6:The following faults are simulated: faults in components and assemblies involving D.C. PRIMARY DISTRIBUTION and SECONDARY DISTRIBUTION.5.3.7 Unattended equipmentModification to 5.3.7:Replace short-circuited with disabled in the third paragraph.JUNE 6, 2008SUBJECT 180110UL
45、 COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL5.102 D.C. primary distribution equipmentAddition:D.C. PRIMARY DISTRIBUTION equipment is to be evaluated for short-circuit withstand.The equipment shall be mounted in a manner representing the most
46、 severe condition of intended use inregard to the following: Enclosure size; Spacings between live parts and grounded metal; and Mounting position.The line terminals shall be connected to the supply circuit. The load terminals shall be connected to thenecessary resistance or impedance, when needed.A
47、 dummy fuse shall be a copper bus or tube, having a size equivalent to the blade (or ferrule) of the fusefor which the fuseholder is intended to accommodate. Each of these buses or tubes may be individuallyreinforced to enable it to withstand the test forces.The equipment shall be tested with the en
48、closure connected through a 30 A cartridge fuse to thegrounded conductor. This connection is to be made to the load side of the limiting impedance by a 10AWG copper wire having a length of 1.83 m (6 ft) or less.The open-circuit voltage is to be 100 110 percent of the rated voltage of the equipment.
49、The circuits shallhave a recovery voltage equal to or greater than the rated voltage of the device. A time constant is notspecified, however, an inductive time constant may be used.During the tests, the following shall apply:a) The fuse connected to the enclosure shall not open;b) There shall not be breakage to the extent that the integrity of the mounting of live parts isimpaired; andc) There shall not be electrical nor mechanical malfunction.A circuit capable of providing the short circui
