1、AIEE No. 92 Dec. 1962 Q*Va“v o 3f Recommended Practice for A-C SYSTEM VOLTAGE NOMENCLATURE for INDUSTRIAL AND COMMERCIAL POWER SYSTEMS Published by AMERICAN INSTITUTE OF ELECTRICAL ENGINEERS 345 East 47th Street, New York 17, N. Y. CONTENTS Page NEED TO REVIEW NOMENCLATURE 3 PREFERRED VOLTAGE NOMENC
2、LATURE FOR HIGH-, MEDIUM-, AND LOW-VOLTAGE SYSTEMS 6 CONCLUSIONS 8 ACKNOWLEDGMENT The Institute wishes to acknowledge its indebtedness to those who have so freely given of their time and knowledge to the preparation of its many publications. This Recommended Practice was prepared by a Working Group
3、of the Codes and Standards Subcommittee of the AIEE Industrial and Commercial Power Systems Committee. The mem bership of this Group was: D. S. Brereton, Chairman A. J. Bisson R. F. Lawrence H. J. Donnelly N. Peach 2 A-C SYSTEM VOLTAGE NOMENCLATURE FOR INDUSTRIAL AND COMMERCIAL POWER SYSTEMS Nomencl
4、ature for alternating-current system voltage should include designations for nominal system voltages and, associated with each nominal voltage: (1) an iden tification of the minimum and maximum acceptable limits for the system operating voltage under favorable and tolerable conditions, and (2) an id
5、entification by voltage rating of devices and equipment to be applied on each system. The AIEE Industrial and Commercial Power Systems Committee has documented preferred system voltage no menclature for industrial plant and commercial building power systems in Tables 1(A), 1(B), and II. It is in ten
6、ded that this information be useful to plant engineers, power-system engineers, application engineers, consulting engineers, electrical contractors, and equipment manufac turers in understanding current system voltage nomencla ture. In addition, a comparison is made to current electric utility power
7、-system practice. This report represents the unanimous agreement of the Working Group with the approval of the Industrial and Commercial Power Systems Committee. Every attempt was made to incorporate preferred practice as well as to include existing practice in industrial and commercial use, recogni
8、zing also electrical utility use. It is the objective that the preferred practices in this report be followed, and that due consideration be given in any Standards revision. Need to Review Nomenclature The only nationally accepted Standard for system voltage designations is the Edison Electric Insti
9、tute (EEI)-Na tional Electrical Manufacturers Association (NEMA) “Guide for Preferred Voltage Ratings for A-C Systems and Equipment.“1 It is recognized by this Committee that the 1949 revision of this Standard incorporated many sig nificant improvements and covered a broader documenta tion of the ra
10、tings for various devices and equipments. It is also recognized that, under the sponsorship of the EEI, the Standard is primarily directed towards the electrical utility field. A portion of this Standard was extracted, modified, and placed in the AIEE publication, “Electric Power Distribu tion for I
11、ndustrial Plants.“2 The system voltage designa tions had to be modified because the Standard does not include all of the presently accepted preferred industrial voltages. To illustrate, the EEI-NEMA Standard does not list the 13,800-volt system and gives preference to the 7,200-volt electrical utili
12、ty system over the 6,900-volt indus trial system. As a result, the Committee felt there was a need for further clarification in industrial and commercial power systems of (1) the preferred system voltages, as well as (2) the method of identifying the voltages. A very comprehensive AIEE paper was pre
13、sented as a report of this Committee at the 1957 AIEE Summer Gen eral Meeting. This “Report of Industrial Voltage Require ments“ (unpublished) covered a definition of terms, and an extensive review of the effect of voltage drop and-volt age spread for the industrial system. The report also in cluded
14、 a comprehensive recommendation on transformer voltage ratings and their effect on utilization equipment. It should be noted that the conclusions of this paper re garding system voltage nomenclature were not completely included in the American Standard. It is anticipated that the American Standards
15、Associa tion will revise their Standard C84.1-1954,1 and it is appro priate for a revised Standard to give “equal treatment“ to the preferred system voltages applied in industrial plants and commercial buildings. RECOMMENDED NOMENCLATURE The preferred system voltages are presented in Table 1(A), “Pr
16、eferred System Voltage Nomenclature, Three-Phase Systems“; Table 1(B), “Preferred System Voltage Nomenclature, Single-Phase Systems“; and Table II, “Preferred Voltage Ratings for A-C Equipment.“ In these tabulations, a comparison is made of the pre ferred nominal system voltage for industrial and co
17、mmer cial power systems, as well as electrical utility power sys tems. In some cases, it was necessary to expand the tables to cover industrial voltages omitted from the Amer ican Standard. The documentation uses the generally ac cepted minimum and maximum voltages for the favorable zone and tolerab
18、le zone as given in the Standard. Favorable zone and tolerable zone voltages are listed using the technique of the American Standard, for the fol lowing three conditions: 1. Voltages at point of utilization equipment. 2. Primary voltages at distribution transformers. 3. Voltages at substations or on
19、 subtransmission or transmission systems. The widespread and extensive practice of applying power systems for industrial plants is to use three-phase systems. Because of this practice, the industrial plant operator iden tifies the name of his system by the nomenclature on the supply transformer. As
20、an example, for medium-voltage systems, the indus trial plant operator will identify his system as a 13.8-kv system if it is supplied by a transformer rated 13,800 volts. This practice should be continued. Similarly, for low-voltage systems, it has also been the practice to identify the system nomin
21、al voltage by using the same voltage as the rating on the nameplate of the transformer. To illustrate, it has been the practice to iden-Table 1(A). Preferred System Voltage Nomenclature, Three-Phase Systems Electrical Utility Power Power Systems * Preferred Nominal System Voltage LjC 4-wire Wye 4 r-
22、vux * 3-wire Wye or Delta Voltage Zones Favorable Zone Minimum Maximum Tolerable Zone Minimum Maximum Systems f Preferred Nominal System Voltage 4-wire Wye 45: 3-wire Wye or Delta VOLTAGES AT POINT OP UTILIZATION EQUIPMENT Low-Voltage Systems 208Y/120 460Y/265(b) 230(a) 460(a) 575(a) 197Y/114 210 42
23、0 434Y/250 525 (94.7%) (91.3%) (91.3%) (94.3%) (91.3%) 216Y/12S 240 480 480Y/277 600 (103.8%) (104.3%) (104.3%) (104.3%) (104.3%) 193Y/111 200 400 422Y/244 500 (92.4%) (87.0%) (87.0%) (91.7%) (87.0%) 220Y/127 250 500 500Y/288 625 (105.8%) (108.7%) (108.7%) (108.7%) (108.7%) 120/208Y 265/460Y(b 230(a
24、) 460(a) 575(a) Medium-Voltage Systems 2400 4160(c) 4800 6900(d) 13.800(b) 2200 3810 4400 6320 12,630 (91.7%) (91.7%) (91.7%) (91.7%) (91.7%) 2450 4240 4900 7050 14,100 (102.1%) (102.1%) (102.1%) (102.1%) (102.1%) 2100 3630 4200 6040 12,080 (87.5%) (87.5%) (87.5%) (87.5%) (87.5%) 2540 4400 5080 7300
25、 14,600 (105.8%) (105.8%) (105.8%) (105.8%) (105.8%) 2400 4160(c) 4800 6900(d) PRIMARY VOLTAGES AT DISTRIBUTION TRANSFORMERS Medium-Voltage Systems 2300 2300/4000Y 4600 6900 4600/8000Y 11,000 6900/12.000Y 12,600 7270/12,600Y 13,000 (95.8%) (95.8%) (95.3%) (95.8%) (95.8%) (91.6%) (95.8%) (95.4%) (95.
26、4%) (90.3%) 2500 (104.2%) 2500/4330Y (104.2%) 5000 (104.2%) 7500 (104.2%) 5000/866OY (104.2%) 12,500 (104.2%) 7500/13.000Y (104.2%) 13,800 (104.5%) 7960/13.800Y (104.5%) 14,500 (100.7%) 2200 2200/3810Y 4400 6600 4400/7620Y 10,500 6600/11.450Y 12,100 7O00/12.100Y 12,600 (91.7%) (91.7%) (91.7%) (91.7%
27、) (91.7%) (87.4%) (91.7%) (91.7%) (91.7%) (87.4%) 2600 (108.3%) 2600/4500Y (108.3%) 5200 (108.3%) 7800 (108.3%) 5200/9000Y (108.3%) 13,000 (108.3%) 7800/13,500Y (108.3%) 14,300 (108.3%) 8250/14.300Y (108.3%) 15,000 (104.2%) 2400/4160Y 4800/8320Y 7200/12.470Y 7620/13.200Y 1 2400 4800 7200 12,000 13,2
28、00 14,400 VOLTAGES AT SUBSTATIONS OR ON SUBTRANSMISSION OR TRANSMISSION SYSTEMS Medium-Voltage Systems (91.7%)| (91.7%) (91.7%)| (91.7%) (91.7%) (91.7%) (91.7%) (87.4%) (91.7%) (91.7%) (91.7%) (91.7%) (87.4%) 2400 4160(c) 4800 6900(b) 3.800(b) 2300 4000 2300/4000Y 4600 6600 6900 4600/8000Y 11,000 69
29、00/12.000Y 12,600 7270/12.600Y 13,200 13,000 (95.8%) (95.8%) (95.8%) (95.8%) (95.8%) (95.8%) (95.8%) (91.6%) (95.8%) (95.4%) (95.4%) (95.8%) (90.3%) 2600 4500 2600/4500Y 5200 7470 7800 5200/9000Y 13,000 7800/13.50OY 14,300 8250/14,300Y 14,950 15,000 (108.3%) (108.3%) (108.3%)| (108.3%) (108.3%) (108
30、.3%) (108.3%) (108.3%) (108.3%) (108.3%) (108.3%) (108.3%) (104.2%) 2200 3810 2200/3910Y 4400 6320 6600 4400/7620Y 10,500 6600/11.450Y 12,100 7000/12.100Y 12,630 12,600 2750 (114.6%) 4760 (114.6%) 2750/4760Y (114.6%) 5500 (114.6%) 7900 (114.6%) 8250 (114.6%) 5500/952OY (114.6%) 13,200 (110.0%) 7920/
31、13.700Y (110.0%) 14,500 (110.0%) 8320/14.500Y (110.0%) 15,000 (108.4%) 15,500 (107.7%) 2400/4160Y 4800/8320Y 7200/12.470Y 7620/13.200Y 2400 4800 7200 12,000 13,200 14,400 23,000 27,600 34,500 46,000 69,000 115,000 138,000 161,000 230,000 See Notel mgn-voita See Notel ige system 20,400 24,500 30,600
32、40,000 60,000 100,000 120,000 140,000 200,000 s (88.7%) (88.7%) (88.7%) (86.9%) (86.9%) (86.9%) (86.7%) (86.9%) (86.9%) 25,800 31,000 38,000 48,300 72,500 121,000 145,000 169,000 242,000 (112.2%) (112.3%) (110.0%) (105.0%) (105.1%) (105.1%) (105.0%) (105.0%) (105.2%) 23,000 27,600 34,500 46,000 69,0
33、00 115,000 138,000 161,000 230,000 * Data, in part, extracted from reference 2. t Data, in part, extracted from reference 1. (a) Differs from ASA C84.1-1954 in nominal voltage only. (b) Additions not found in ASA C84.1-1954. (c) Appears as 2400/4160Y volts in ASA C84.1-1954; limits unchanged. (d) Vo
34、ltage limits differ from ASA C84.1-1954. Note 1: For systems with nominal voltages above 13,800 volts, the designation of a “favorable zone“ has been omitted as being somewhat less necessary than for the lower voltages. 4 Table 1(B). Preferred System Voltage Nomenclature, Single-Phase Systems Indust
35、rial and Commercial Power Systems * Preferred Nominal System Voltage : 3-wire . 1 2-wire Electrical Utility Power Systems f Voltage Zones Favorable Zone Minimum Maximum Tolerable Zone Minimum Maximum Preferred Nominal System Voltage : 3-wire T , 2-wire VOLTAGES AT POINT OF UTILIZATION EQUIPMENT Low-
36、Voltage Systems 120/240 120 110 (91.7%) 110/220 (91.7%) 220/440 (91.7%) 125 (104.2%) 125/250 (104.2%) 250/500 (104.2%) 107 (89.2%) 107/214 (89.2%) 214/428 (89.2%) 127 (105.8%) 127/254 (105.8%) 254/508 (105.8%) 120/240 240/480 120 *t See footnotes, Table 1(A). Table II. Preferred Voltage Ratings for
37、Alternating-Current Equipment Preferred Nominal System Voltage Generator Rated Voltage Transformer Secondary Rated Voltage Transformer Primary Rated Voltage Switchgear Nominal Rated Voltage Capacitor Rated Voltage Motor and Control Rated Voltage Ballast Rated Voltage Single-Phase Systems and Single-
38、Phase Components Applied on Three-Phase Systems 120 120/240 208Y/120, 3-phase 460Y/265, 3-phase 208Y/120 230 460Y/265 460 575 2,400 4,160 4,800 6,900 7,200 12,000 7,200/12,470Y 13,200 13,800 14,400 120 120/240 125/216Y, 3-phase 277/480Y, 3-phase 125/216Y 139/240Y 277/480Y 277/480Y 346/600Y 1,388/2,4
39、00Y 2,400/4,160Y 2,770/4,80OY 3,980/6,90OY 3,980/6,900Y 7,210/12,500Y 7,21O/12,50OY 7,970/13,8O0Y 7,97O/13,80OY 8,320/14,400Y 120 120/240 216Y/125, 3-phase 480Y/277, 3-phase 216Y/125 240Y/139 or 240 480Y/277 480Y/277 600Y/346 or 600 2,400Y/1,388 or 2,400 4,160Y/2,400 4,800Y/2,770 or 4,800 6,900Y/3,9
40、80 7,2OOY/4,160 12,000Y/6,920 12,470Y/7,200 13,200Y/7,610 13,800Y/7,970 13,800Y/7,970 120 240 120 480 120 240 240 480 Three-Phase Low-Voltage Systems 208 240 480 480 600 240 240 480 480 600 Three-Phase Medium-Voltage Systems 2,400 4,160 4,800 6,900 7,200 12,000 12,000 13,200 13,800 13,800 2,400 4,16
41、0 13,800 or 7,200 7,200 13,800 or 7,200 13,800 13,800 13,800 13,800 14,400 230 or 240 230 or 240 460 or 480 216 or 230 or 240 230 or 240 460 or 480 460 or 480 575 or 600 2,400 2,400 or 4,160 2,770 or 4,800 4,160 or 6,640 4,160 or 7,200 7,200 or 12,470 7,200 or 12,470 7,620 or 13,800 7,960 or 13,800
42、7,960 or 13,800 or 14,400 115 230 115* 208 or 220 220 440 440 550 2,300 4,000 4,600 6,600 6,600 11,000 13,200 13,200 13,200 120 236 or 240 120* 265* or 277* 208t 236t or 240t 460t or 480t 460t or 480t * Line-to-neutral rating. t Line-to-line rating. 5 Table III. Application of Voltage Nomenclature f
43、or Medium-Voltage Systems Voltage Percent of System Voltage Voltage Spread, % Favorable zone: maximum voltage 2,450 System Nominal Voltage and transformer voltage rating 2,400 Motor voltage rating 2,30Favorable zone: minimum voltage 2,20Favorable zone: maximum voltage 4,240 System Nominal Voltage an
44、d transformer voltage rating 4,160 Motor voltage rating 4,00Favorable zone: minimum voltage 3,81Favorable zone: maximum voltage 4,900 System Nominal Voltage and transformer voltage rating 4,800 Motor voltage rating 4,60Favorable zone: minimum voltage 4,40Favorable zone: maximum voltage 7,050 System
45、Nominal Voltage and transformer voltage rating 6,900 Motor voltage rating 6,60Favorable zone: minimum voltage 6?32Favorable zone: maximum voltage 14,100 System Nominal Voltage and transformer voltage rating 13,800 Motor voltage rating 13,20Favorable zone: minimum voltage 12,63102.1 100.0 95.9 91.7 1
46、02.1 100.0 96.1 91.7 102.1 100.0 95.9 91.7 102.1 100.0 95.7 91.7 102.1 100.0 95.7 91.7 +2.1 8.3 +2.1 8.3 +2.1 8.3 +2.1 8.3 + 2.1 -8.3 10.4 . 10.4 10.4 10.4 10.4 tify a system service from a 480-volt transformer as a 480-volt system. With the acceptance of more suitable voltage nomenclature for low-v
47、oltage industrial systems, it is recommended that the system just described now be identified as a 460-volt system. DESIGNATION FOR THREE-WIRE AND FOUR-WIRE THREE-PHASE SYSTEMS It is desirable and conveniently possible to distinguish between three-wire and four-wire three-phase power sys tems by mea
48、ns of system voltage nomenclature. To illus trate, the four-wire 460-volt system is designated as 460Y/265 volts (previously identified as 480Y/277 volts), and the three-wire system is simply designated as 460 volts. The practice in the industrial system has been to iden tify the four-wire system by
49、 mentioning the line-to-line voltage before the line-to-neutral voltage, based on the American and NEMA Standards of designating three-phase transformers. A different practice has been followed in identifying the nominal system voltages in the electrical utility field, such as the 120/208Y-volt or 265/460Y-volt system. The technique of including the line-to-neutral voltage (whether it is placed after the line-to-line voltage in the case of the industrial or commercial power system, or placed before the line-to-line voltage to indicate the elec trical utility practice
