標準號：UL 845-2005
中文標準名稱：電動機控制中心
英文標準名稱：Motor control centers
標準類型：K20
發布日期：2005/8/31 12:00:00
實施日期：1999/12/31 12:00:00
中國標準分類號：K20
國際標準分類號：29.160.30
適用范圍：1.1 Products covered: 1.1.1 This standard applies to motor control centers to be used in accordance with the U.S. National Electrical Code, ANSI/NFPA 70, the Canadian Electrical Code, Part 1, CSA C22.1, and the Mexican Electrical Installations (Utility), NOM-001-SEDE. 1.1.2 These requirements cover motor control centers for use on circuits having available short-circuit currents not more than 200000 A rms symmetrical or 200000 A dc. 1.1.3 This standard applies to single- and three-phase 50 and 60 Hz and dc motor control centers rated not more than 600 V ac or 1 000 V dc. 1.1.4 Requirements for fire pump controllers are as provided in Annex c, item 11. 1.2 Products not covered: These requirements do not cover switchboards or panelboards intended for the control of electric light and power circuits, nor do they cover an individual unit for this purpose. Such units, however, that consist of manually or automatically operated switches, branch-circuit or service-circuit circuit-breakers, overcurrent-protective devices, or the like may be used within a motor control center. 1.3 Equipment: 1.3.1 A motor control center can contain, but is not limited to, any combination of equipment such as the following: a) full-voltage reversing or non-reversing combination motor control units; b) full-voltage multispeed combination motor control units; c) reduced-voltage part-winding, wye-delta or auto-transformer combination motor control units; d) solid-state industrial controllers, such as adjustable-speed drives, programmable controllers, protective relays, and the like; e) lighting or distribution panelboards; f) feeder-tap units; g) incoming-line equipment, such as main lugs, fusible switch, isolation switch, or circuit-breaker; h) control or lighting transformers; i) special equipment assemblies; j) combination contactor units. 1.3.2 The foregoing equipment can contain, but is not limited to, such items as pushbuttons, selector switches, indicating lights, control transformers, control circuit fuses, and auxiliary devices incorporated as an integral part of the units. 1.4 Units of measurement The first values given are SI (metric) units. Alternate measurements shown in parentheses are US customary units, which sometimes are not strict conversions. This new edition includes the following revisions: 1. Inclusion of applicable construction and performance requirements for combination motor controllers from UL 508, Standard for Industrial Control Equipment. 2. Removal of enclosure construction requirements and spray test from UL 845 and inclusion of reference to UL 50, Standard for Enclosures for Electrical Equipment for enclosure requirements. 3. Inclusion of selected requirements and informative Annex H application information from NEMA ICS 18 - 2001, Motor Control Centers. 4. Use of metric units as primary requirement with English units in parenthesis. 5. Inclusion of requirements for feeder and main units. 6. Revision to scope to permit dc rated motor control centers up to 100 V dc. 7. Inclusion of new and revised requirements which increase the level of performance or add new marking requirements compared to the current UL 845 standard. 8. New requirements that provide alternate constructions or options not previously included in UL 845.