1、ATIS-0600311.2017 American National Standard for Telecommunications DC Power Systems Telecommunications Environment Protection Alliance for Telecommunications Industry Solutions Approved December 23, 2016 American National Standards Institute, Inc. Abstract This standard addresses the installation o
2、f dc power systems within controlled or limited access areas that convert commercial ac to dc voltages of 160 volts or less and those that convert from one dc level to another of 160 volts or less. ATIS-0600311.2017 ii Foreword The information contained in this Foreword is not part of this American
3、National Standard (ANS) and has not been processed in accordance with ANSIs requirements for an ANS. As such, this Foreword may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standar
4、d. The Alliance for Telecommunication Industry Solutions (ATIS) serves the public through improved understanding between providers, customers, and manufacturers. The Sustainability in Telecom: Energy and Protection (STEP) Committee formerly the Network Interface, Power, and Protection Committee (NIP
5、P) engages industry expertise to develop standards and technical reports for telecommunications equipment and environments in the areas of energy efficiency, environmental impacts, power, and protection. The work products of STEP enable vendors, operators and their customers to deploy and operate re
6、liable, environmentally sustainable, energy efficient communications technologies. STEP is committed to proactive engagement with national, regional, and international standards development organizations and forums that share its scope of work. ANSI guidelines specify two categories of requirements:
7、 mandatory and recommendation. The mandatory requirements are designated by the word shall and recommendations by the word should. Where both a mandatory requirement and a recommendation are specified for the same criterion, the recommendation represents a goal currently identifiable as having disti
8、nct compatibility or performance advantages. Suggestions for improvement of this document are welcomed. They should be sent to the Alliance for Telecommunications Industry Solutions, STEP, 1200 G Street NW, Suite 500, Washington, DC 20005. At the time it approved this document, STEP, which was respo
9、nsible for its development, had the following leadership: K. Biholar STEP Chair (Nokia) J. Krahner, STEP Vice Chair (Cisco) E. Gallo, STEP NPS Chair (Ericsson) J. Jackson, STEP NPS Vice Chair (AT 2. Battery string; 3. Charge bus; 4. Discharge bus; 5. Primary power distribution; and 6. Secondary powe
10、r distribution. 5.3 Rectifier/Chargers Rectifier/chargers functionally convert ac input power to regulated dc output power. Normally two or more rectifier/chargers are provided with their dc outputs connected in parallel to a common power bus. 5.4 Charge Bus The charge bus shall be designed and inst
11、alled so that equipment is accessible for installation or removal while the bus is electrically hot. Insulated conductors, when used for the charge bus, should be run directly between rectifier/charger output and a terminal plate at the battery terminals, or terminate at a rigid splice plate at one
12、or both ends - i.e., at the rectifier/charger(s) output and battery terminals. 5.5 Battery string A battery string is a group of electro-chemical cells connected in series by intercell connectors. More than one battery string may be provided in parallel to increase the energy storage capacity. 5.6 D
13、ischarge bus The charge bus (see 5.4) and the discharge bus may be combined as one and the same. ATIS-0600311.2017 6 Insulated conductors, when used for the discharge bus, may run directly between the battery terminals and the primary distribution network, or terminate at a rigid splice plate at one
14、 or both ends - i.e., at the battery terminals and at the distribution. ATIS-0600311.201x 7 Figure 1 - Typical DC Power System ATIS-0600311.201x 8 5.7 Primary distribution Primary distribution is the portion that includes the first overcurrent protection devices downstream from the discharge bus as
15、shown in Figure 1. The primary distribution system contains a powerboard that houses the overcurrent protection devices and the downstream power distribution network that feeds the secondary distribution. In some instances, the primary distribution serves the load equipment directly, eliminating the
16、 secondary distribution. Primary distribution powerboards shall meet the requirements of 7.8.4. Overcurrent protection devices shall be either fuses or circuit breakers that meet the requirements of 7.3 and 7.4. They are selected to protect conductors. 5.8 Secondary distribution Secondary distributi
17、on is an intermediate protection network between the primary distribution and the load equipment, as shown in Figure 1. The secondary distribution network contains a powerboard that houses the overcurrent protection devices, and the downstream power conductors to the load equipment. Secondary distri
18、bution may be located adjacent to the primary distribution powerboard or remotely on the same or different floors. Secondary distribution powerboards shall meet the requirements of 7.8.4. Overcurrent protection devices shall be either fuses or circuit breakers that meet the requirements of 7.3 and 7
19、.4. They are selected to protect conductors. 6 Grounding or they shall be permanently identified with a green or green/yellow marking as a grounding conductor at the terminations. An insulated conductor in a multiconductor cable used as a grounding or bonding conductor shall be permanently identifie
20、d as above. 8.8 Circuit disconnects 8.8.1 Disconnect requirement This standard shall not require any circuit-disconnect devices between the battery and charger/rectifiers or between the battery and the input to the primary distribution. If an overcurrent-protection device is used in the distribution
21、, a circuit disconnect shall be required. Third-party certified overcurrent protection devices or fuseholders, certified as disconnect devices, may be used. 8.8.2 Return conductors Return conductors may have a disconnecting device connected in series, provided that the device is a multiple-pole devi
22、ce synchronized to break all conductors of the circuit when operated. ATIS-0600311.2017 14 8.8.3 Grounding conductors No disconnect device shall be connected in series with any frame or equipment grounding conductor. 8.9 Guarding 8.9.1 Physical damage prevention Where there is a possibility of unint
23、entional physical damage to equipment or conductors, guards or enclosures shall be provided. 8.9.2 Rigid uninsulated bus When a rigid uninsulated power bus is located adjacent to or in the immediate path of normal or emergency exits, the exposed conductive parts shall be insulated or guarded against
24、 contact. 8.9.3 Live parts (160-volt-dc class) Live parts shall be marked or guarded against unintentional contact if at a height of less than 7 feet above the floor. 8.10 Clearances and working space 8.10.1 Conductive part spacings The distance between bare conductive parts shall not be less than t
25、hat shown in Table 2. Spacing at third-party certified switches, fuseholders, or circuit breakers, and the spacings in third-party certified equipment and components shall be exempt from these minimum spacing requirements. 8.10.2 Field wiring terminals Field wiring terminals shall meet the clearance
26、 spaces given in Table 2. 8.11 Overcurrent protection Primary- and secondary-distribution circuits shall be protected by overcurrent protection devices having a rating or setting proper for the application. Charge and discharge circuits shall not require overcurrent protection. These circuit conduct
27、ors, when not provided with overcurrent protection, shall be routed separately from overcurrent protected conductors. 8.11.1 Scope This subclause of the standard provides the general requirements for overcurrent protection of primary- and secondary-distribution circuits of not more than 160 volts dc
28、. Overcurrent protection for conductors is provided to open the circuit if the current reaches a value that will cause excessive or dangerous temperatures in conductors or conductor insulation. 8.11.2 Location in circuit An overcurrent device, when required, shall be connected at the point where the
29、 conductor to be protected receives its supply. ATIS-0600311.2017 15 8.11.3 Readily accessible Overcurrent devices shall be readily accessible. 8.11.4 Not exposed to physical damage Overcurrent devices shall be located where they will not be exposed to physical damage. 8.11.5 Frame internal overcurr
30、ent protection Where overcurrent protection is used for equipment or components internal to an equipment frame, it shall not be used as a substitute for primary- or secondary-distribution circuit protection. 8.11.6 Remote sense leads Ungrounded remote sense leads from each rectifier/charger shall be
31、 protected against overcurrent or short-circuit faults. Overcurrent protection devices or current limiting circuits shall be acceptable methods for protecting these leads. 9 Wiring methods 9.1 Conductor ampacity and size Ampacities of conductors and the insulation type required for suitability shall
32、 be as referenced in Tables 3 and 4. The ampacity of rigid bus conductors is given in Table 5. 9.2 Conductors of different systems Power conductors of alternating current or direct current shall be permitted to occupy the same wiring enclosure or cable rack, provided all conductors have an insulatio
33、n voltage rating equal to the maximum circuit voltage rating of any conductor within the enclosure or cable rack. See 9.7.3. 9.3 Wiring in ducts, plenums, raised floors, and suspended ceilings 9.3.1 Ducts and plenums No conductors shall be located in ducts or plenums used for the transfer of dust, l
34、oose stock, or flammable vapors. 9.3.2 Raised floors and suspended ceilings non air handling spaces Spaces below raised floors and above suspended ceilings, when not used for air handling, shall be permitted to contain all insulated wiring systems described herein. The only uninsulated conductor per
35、mitted shall be the grounding conductor. 9.3.3 Raised floors and suspended ceilings air handling spaces (To be determined.) ATIS-0600311.2017 16 9.4 Bends The bend radii of field-installed conductors shall be sufficiently large to ensure that no damage is done to the insulation or the conductor. The
36、 minimum-bend radius for coarse concentric-lay stranded insulated cable shall be as listed in Table 6. The cable-bend radius shall be measured on the inside bend. 9.5 Conductors for general wiring 9.5.1 Scope The following paragraphs provide general guidelines in the inspection of field-installed co
37、nductors used in dc power systems. Topics addressed include conductor type, ampacity, and environment. 9.5.2 Conductors Conductors (individually insulated wire, or rigid bus bars) shall be aluminum, copper-clad aluminum, or copper. Conductors, and their installations, shall be suitable for the condi
38、tion of the location, including moisture, corrosion, ambient temperature, and mechanical protection factors. All conductors shall be supported such that excessive pressure is not transmitted to the electrical termination of the conductor. Spacings of conductors shall be such that the operating tempe
39、rature of each conductor shall not exceed its designated limit. Open wiring of conductors shall be acceptable, provided the conductors are protected from mechanical injury. The terminations of conductors shall be made by acceptable wire connectors for that particular conductor as evaluated in its ow
40、n environment. Crimp-type (irreversible compression-type) terminations shall be made using third-party certified crimping devices. 9.5.3 Stranded conductors Termination of stranded conductors shall be with approved wire connectors such that all strands are contained within the connector openings. 9.
41、5.4 Bus conductors Spacing of bus bars shall be such that the operating temperature of each conductor shall not exceed its designated limit. 9.5.5 Conductors in parallel When conductors are electrically joined to form the equivalent of a single conductor, the following conditions shall be met: Cable
42、s shall be the same length. Cables shall be made of the same conductive material and have the same cross-sectional area. Cables shall use the same insulation type. Cables shall all be terminated in the same manner;. Conductors shall be next to, or as close to each other as possible. 9.5.6 Bus duct B
43、us duct shall be defined as a grounded metal enclosure containing factory-mounted rigid bar conductors. The installation and sizing of the bus duct shall be in accordance with the manufacturers guidelines with regard to temperature and environment. ATIS-0600311.2017 17 9.5.7 Cable bus Cable bus shal
44、l be defined as an approved assembly of insulated conductors with fittings and conductor terminations in a completely enclosed metal housing. Installation and sizing of conductors shall be within the manufacturers ratings. 9.6 Cable rack 9.6.1 Scope A cable rack system shall be defined as a unit or
45、assembly of units or sections and associated fittings forming a rigid structural system used to support cables. 9.6.2 Cables permitted Approved single-conductor and factory-assembled, multiconductor-control, signal or power cables shall be permitted, and may be installed in common cable rack systems
46、. See 9.7.3. 9.6.3 Locations not permitted Cable rack systems shall not be used in hoistways or where exposed to severe physical damage. 9.6.4 Construction Cable racks shall have strength and rigidity to provide support for all contained wiring. These rack systems shall be free of sharp edges, burrs
47、, or projections that could damage the conductor insulation; and shall be made of a corrosion-resistant material or shall be protected against corrosion. All systems shall have means to contain the conductors and include fittings or other approved means for changes in directions and elevation of run
48、s. 9.6.5 Installation Cable rack systems shall be installed as a complete system where each run of cable rack is completed before the installation of cables. The system shall be designed to minimize stress to the conductors as they enter from an enclosure or other cable rack. 9.6.6 Partitions and wa
49、lls Cable racks shall be permitted to pass through walls and floors where the installation, including all cables, shall not substantially increase the spread of fire. To accomplish this, openings through which cable racks penetrate fire-resistant walls and floors, shall be firestopped using approved methods. Cable racks shall be accessible with space provided to install and maintain the cables. 9.7 Cable installation 9.7.1 Cable splices Crimp-type (irreversible compression-type) splices and taps shall be permitted within cable racks. Non-crimp splices and taps
