You should consider contributing to our CFE Media editorial team and getting the recognition you and your company deserve. In non-landscaped sites, pruned vegetation and wood are left in place to biodegrade. Some applications require a reduced sound level, such as a large unit in a commercial building with people working close to it. Division 01 - General Requirements Division 02 - Existing Conditions Division 03 - Concrete Division 04 - Masonry Division 05 - Metals Division 06 - Wood, Plastics, and Composites Will I be notified before a tree crew comes to cut trees in my yard? [ILLUSTRATION FOR FIGURE 1 OMITTED]. Therefore, the transformer size required for converting the system voltage from 480 V, 3-phase, 3-wire to 208 Y/120 V, 3-phase, 4-wire is: Transformer size in kVA = 42 kVA x 1.25 = 52.5 kVA. When specifying a transformer to be operated in parallel with existing units, all these parameters should be discussed with the transformer manufacturer. %PDF-1.6 % For a limited time we are offering our logo design services for $29 only. *[L EgptA80~@GI#Q@hxMGPhMgoQ ] $ k. But be careful here: Before applying this voltage, check with the manufacturer's manuals. ; 4 Final files will be provided in any format. 4, on page 44, and when all enclosure hardware is tightened so panels do not vibrate. Yes, there are special circumstances that may include: (1) the proper ANSI cut is not a specified distance from the centerline, (2) the trunk of a mature tree is established within rights of way, (3) the tree is inhabited by an endangered species, (4) the tree is a slow-growing species or (5) there is a Department of Transportation encroachment. hbbd```b``{"@$$)fO8,f`v/~, lb{ 6_DrGH 8Xqf$]v P(9Wl0 v This website uses cookies to improve your experience while you navigate through the website. No one should climb trees that are in the vicinity of power lines. Your Satisfaction is Guaranteed! If this data can be used, the extra cost to carry out tests can be avoided without sacrificing the quality of the transformer. <>/ExtGState<>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> They were great at following our directions to the letter, while adding their own creative flair. 7. The location of a transformer relates directly to how noticeable its sound level appears. What can I do in a transmission right of way? down from each of the ends of the long sides. Usually, lateral bracing and/or an extra solid anchorage will be required. All rights reserved. Take care not to damage the base or tip it over. But opting out of some of these cookies may affect your browsing experience. 3, on page 42. WebDuke Energy Transmission DECorp: Duke Energy Midwest . <> Click Here to see our Portfolio. When an act of God (such as lightning, ice storms, high winds, hurricanes, tornadoes) or other natural events cause trees or other vegetation to fall across power lines and damage facilities, we cut the trees and brush so poles and lines can be replaced and re-energized. As appropriate, you should make arrangements to adequately support the incoming/outgoing connecting cables to ensure that there is no mechanical stress imposed on transformer bushings and connections. Dry-type transformers have sound levels that are somewhat Transformers change voltage levels to supply electrical loads with the voltages they require. When people identify downed lines or trees touching power lines and act wisely, it minimizes the risk from trees contacting power lines. In maintained or landscape settings, our policy is to dispose of any small limbs and brush. The tap setting should also be verified for the proper voltage. For transformers placed outside that are 2000kVA and above, you may wish to have the soil examined. % With Duke Energys Builder Portal, you have the tools you need to get it done, right at your fingertips. When you start making the connections between the transformer's terminals and the incoming and outgoing conductors, carefully follow the instructions given on the nameplate or on the connection diagram. Well remember your selection for future visits. This may include personalization of content and ads, and traffic analytics. The cookies is used to store the user consent for the cookies in the category "Necessary". Some manufacturers require that the megohmmeter readings and date of energizing be sent to them within a specified time after the transformer is placed in service for the warranty to be valid. The difference is they contain an enclosed tank with nitrogen or other dielectric gas to protect the windings. Oil-filled transformers are constructed with the windings encased in an oil-tight tank filled with insulating mineral oil. Usually, additional testing means there will be an increase in transformer cost. A point of contact will be provided should you have questions or concerns about the upcoming vegetation work. Trees are assessed on a case-by-case basis. It is good practice to regularly test this type of transformer in order to determine dielectric breakdown, which affects its useful life. Our Professional Package is designed for our small business, or just-starting-out business clients. The article in this issue covers installation procedures you should consider to help assure your transformer will function properly and safely, and it's focused on installation practices that are common for both dry-type and liquid-filled transformers. The installation of power transformers and transformer vaults must comply with the requirements of National Electrical Code (NFPA 70) article 450 and specific local authority having jurisdiction requirements. The loads, which are calculated as part of the building electrical system design phase, are shown in the construction documents respective equipment schedules in VA or kVA. Revision 009 Effective Date 02/18/2022 . The usual sound levels for liquid-filled transformers range from 40 dB to 60 dB for units below 500kVA, about 65 dB for units between 4000kVA to 5000kVA, 73 dB for transformers with ratings between 6000kVA to 7500kVA, and 76 dB for units between 8000kVA and 10,000kVA. You may also hire a company to remove the debris or contact your local public works to see if they remove yard debris. Preliminary inspection upon receipt of transformer. North America | April 5, 2018. . You should arrange for an insulation resistance test to be carried out to make certain that no windings are grounded. endstream endobj startxref The electrical phase characteristics associated with the transformers primary side is 3-phase, 3-wire or Delta connected. Correct fan rotation should be visually verified as well as by checking indicator lights if they are installed. If appropriate, supports should be used so that the transformer enclosure is not crushed when the unit is lifted. However, they do protect the transformer itself from damage caused by harmonics. Part 2 will address installation procedures for dry- and wet-type transformers, the latter being fully assembled. If in doubt about clearances, do not hesitate to call the transformer manufacturer. Dry-type transformers have sound levels that are somewhat higher. They are very professional, and the team knows their craft. Duke Energy Florida Power & Light Gulf Power Company Oklahoma Gas & Electric Tampa Electric 6. Trees can disrupt power in a number of ways. Necessary cookies are absolutely essential for the website to function properly. Each test has a particular objective that helps determine a transformer's suitability for use. For example, the code-based demand load of a 208 Y/120 V, 3-phase, 4-wire panelboard is 42 kVA, which does do not include spare capacity for future growth. endobj The above simple calculation meets the intent to achieve the normal life expectancy of a transformer, which is based on the following basic conditions: Transformer selection starts with the kVA rating required to supply the loads connected in the electrical system. However, their operating principles will remain with the same. These cookies do not store any personal information. What fantastic professionals to work with. The usual sound levels for liquid-filled transformers range from 40 dB to 60 dB for units below 500kVA, about 65 dB for units between 4000kVA to 5000kVA, 73 dB for transformers with ratings between 6000kVA to 7500kVA, and 76 dB for units between 8000kVA and 10,000kVA. Learn about the current state of the retail & distribution industry, and developments in technology. All Rights Reserved. [CDATA[// >
