Transformers are designed with provisions for lifting, jacking, and/or rolling. This may call for compromises regarding the length of the conductors going to and/or from the transformer. Duke Energy Corporation. [ILLUSTRATION FOR FIGURE 2 OMITTED]. It's the responsibility of the property owner to maintain the growth of any trees interfering with the lighting pattern. We will most definitely return should we have additional needs!! A careful examination should be made to ensure that all electrical connections have been properly carried out and that the correct ratio exists between the low and high-voltage windings. Air intake openings in the wall may be necessary or a larger minimum surrounding The insulation resistance test should be conducted immediately prior to energizing the transformer or the beginning of the dielectric test. 847 0 obj <>stream hbbd```b``z"H-dfH`?dirdl"?$L@{b`Ig` / h[oWcp :\_H84$p~U==$W9A{fzQ!wZkzjgybveni\+\-\z&w:%HE*:Er;cWc You should use commercially available, properly sized, UL-listed mechanical- or compression-type lugs. The specific requirements start in 110.26 (A) and refer to "equipment operating at 1000 volts, nominal, or less to ground andlikely to require examination, adjustment, servicing, In maintained areas, we attempt to provide notification prior to vegetation maintenance work. 4 0 obj If these parameters are different, circulation current will exist in the circuit loop between these units. Usually, lateral bracing and/or an extra solid anchorage will be required. However, if the tree poses a significant reliability risk or cannot be trimmed in a way that provides sufficient clearance until the next scheduled trim cycle while maintaining its health, the tree may be taken down. hb```f eaak \6XBt+eNHPY0?P0dTh D>+30mg`T}n303c2bpa4%u`(00m] 9>b`28 *> Caution is required when operating in parallel. They are useful in areas with a corrosive or dirty atmosphere. Check all of the tap jumpers for proper location and for tightness. They were very attentive to our needs, very detailed with their work, and met the needs of our timetable. Line side (unmetered) and load side (metered) conductors shall not occupy the same raceway or enclosure. They were great at following our directions to the letter, while adding their own creative flair. Large enclosed units with base frame type enclosures may be jacked using the base frame angles. Develop a procedure for inventory of all tools, hardware, and any other objects used in the inspection, assembly, and testing of the transformer. Before energizing the unit, it's very important that you alert all personnel installing the transformer that lethal voltages will be present inside the transformer enclosure as well as at all connection points. Pruning trees around power lines should only be attempted by qualified professionals. Is Duke Energy responsible for cleanup after trimming trees or weather events? I found createlogodesign.com by searching the internet, and decided to try them out without a first hand referral. https://www.facebook.com/ElectricalConstructionMaintenanceMagazine, https://www.linkedin.com/company/electrical-construction-maintenance/. Subsequently, covers or panels should be removed and an internal inspection should be made for damage or displacement of parts, loose or broken connections, dirt or foreign material, and for the presence of water or moisture. When is tree trimming considered an emergency? Personnel should be instructed that should any service work be required to the unit, the lines that power the transformer must be opened and appropriate safety locks and tags applied. North America | April 5, 2018. Both projects included dry-type 480 V, 3-phase to 208 Y/120V V step-down transformers (in NEMA 2 enclosures), ranging from 15 kVA to 112.5 kVA in the electrical system distribution design. This category only includes cookies that ensures basic functionalities and security features of the website. Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. Selecting, sizing transformers for commercial buildings, By using this website, you agree to our use of cookies. All windings should be checked for continuity. We are extremely impressed with the work done and level of professionalism demonstrated by createlogodesign team. 9. clearances listed are duke energy minimum requirements. 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. WebHow it Works. If the unit is installed in a location it shares with other equipment such as motors, pumps, or compressors, the transformer hum will go unnoticed. September 14, 2022. Under certain conditions, trees and tree limbs can conduct power if they come in contact with power lines. We also depend on help from the public. WebAustin Enclosures AB-243212CT/DP1G Duke Power CT Cabinet Austin rainproof boxes are for Wiring or Junction box applications. We have worked with various logo designers, and they are the cream of the crop. When selecting a tree or shrub to plant, it is just as important to consider what you plant as it is where you plant. Our site is customized based on your location. In some locations, Duke Energy may have an easement of varying widths. ^P*#e;dEH?7"\']Ec5>\(zx94|aX7NRc6~l}(} And its important that you follow current NEC practice and applicable local codes. Trees are assessed on a case-by-case basis. The electrical size of the transformer load is rated in kVA. 3, on page 42. An IVM program evaluates vegetation and determines the best methods for maintenance and tree removal to ensure reliable service. Our understanding of their general characteristics will allow the designer and end user to make the proper selection for the electrical system application. *[L EgptA80~@GI#Q@hxMGPhMgoQ ] $ k, `h`` ``{_j j[e13b{@38O=)HpG17hCDC i. When received, a transformer should be inspected for damage during shipment. Retail & Schools Depending upon the size and load requirements of the facility, the large majority of schools (except for some very large universities) and retail facilities are served by Where can recorded transmission easement documents be found? If you see a fallen tree in contact with a power line, immediately contact Duke Energy. If you cannot gradually increase the load, then full load may be applied. This type can be installed in areas with corrosive or dirty atmospheric conditions where it would be impossible to use a ventilated-type transformer. Also, when aluminum conductors are used, give them a protective compound treatment at the terminal as specified by the cable manufacturer. 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. Grounding is necessary to remove static charges that may accumulate and also is needed as a protection should the transformer windings accidentally come in contact with the core or enclosure (or tank for wet types). These cookies track visitors across websites and collect information to provide customized ads. We also use third-party cookies that help us analyze and understand how you use this website. 7. <> Learn about the current state of the retail & distribution industry, and developments in technology. 2144 0 obj <>stream This article will continue in subsequent issues of EC&M. Serious injury or death may result from climbing a tree and making direct contact with or coming too close to an energized line. This does not apply to bottom ventilation openings. This material will provide additional general guidelines for installing and testing both dry-type and liquid-filled transformers for placement into service. For harmonic mitigation, K-rated transformers can be combined with harmonic filters or chokes. The weight distribution should be studied by examining the inside of the transformer enclosure for dry-type units. Before specifying any additional tests, you should contact the manufacturer to find out what data it has accumulated from testing essentially duplicate units. %PDF-1.7 % Duke Energy trims trees to provide reliable service to our customers. Our logos are specifically created respecting the individuality of your company. These procedures are different than rounding of trees over in which limbs are cut at arbitrary points, normally leaving unhealthy stub cuts. They have proactively gone above and beyond to do an exceptional job with everything. Usually, additional testing means there will be an increase in transformer cost. Correct fan rotation should be visually verified as well as by checking indicator lights if they are installed. I was so impressed with the finished result that I've asked them to undertake future work. thick with chamfered edges on top of the base and footings extending 20 in. Our logos are stylish, unique and memorable. You should not remove this coating from tap and line terminals. The specific requirements start in 110.26 (A) and refer to "equipment operating at 1000 volts, nominal, or less to ground andlikely to require examination, adjustment, servicing, or maintenance while energized". I guess the key is whether transformers are likely to requireexamination, adjustment, servicing, or maintenance while energized. What is the time frame expected for the completion of customer-requested tree trimming? The successful operation of a transformer is dependent on proper installation as well as on good design and manufacture. But opting out of some of these cookies may affect your browsing experience. All products used by Duke Energy are registered by the Environmental Protection Agency and approved by appropriate state agencies. In addition, a good design and installation require the proper transformer feeder and overcurrent protection device size based on NEC articles 240, 250, 450, and applicable sections of Article 310 (Figure 2). Energy Efficient Transformer require a minimum of 3`` clearance from ventilated openings. All Duke Energy transmission structure numbers are typically located three-quarters of the way up the pole or on one of the legs of the tower. A protective plating or compound that prevents surface oxidation on the aluminum terminals is usually applied at the factory. Division 01 - General Requirements Division 02 - Existing Conditions Division 03 - Concrete Division 04 - Masonry Division 05 - Metals Division 06 - Wood, Plastics, and Composites Several transformer types rated higher than 600 V for oil insulated type, higher than 35,000 V for dry type, and other transformers rated higher than 600 V are required to be located in vault rooms, which must be built with fire-rated enclosures depending on the transformer type and applicable local authority requirements, when indoors. Member Resources. These practices are approved by internationally recognized tree care associations and are referred to as Integrated Vegetation Management (IVM). Facility Connection Requirements . You may lift transformers with enclosures having lifting lugs by using appropriate slings or chains. Distribution poles are typically the smaller poles seen following roads or property lines through subdivisions and have connections directly to homes or businesses. 300.2 METERED AND UNMETERED CONDUCTORS . Duke Energy contractors have been trained on the proper, safe and environmentally responsible techniques of managing plant growth. Linear loads include resistive heating and induction motors; nonlinear loads are produced by electronic equipment that contributes to the distortion of the electrical power signals by generating harmonics. Performing this action will revert the following features to their default settings: Hooray! Information on minimum wire bending space clearances at terminals for conductors is found in NEC Sec. The cookie is used to store the user consent for the cookies in the category "Other. In non-landscaped sites, pruned vegetation and wood are left in place to biodegrade. From the start Steffi was prompt and responsive. If this isn't possible, you first should contact the manufacturer to explore other options. The transformer is equal to or less than its rated kVA and rated voltage. Necessary cookies are absolutely essential for the website to function properly. Hint: Duct Tape to the Rescue. Our prices are low as compared to that offered by our competitors, as we understand that small business may have limited budgets, but we believe that even they should have the opportunity to get a professionally designed logo which meets their budget. If you see a downed line, immediately contact Duke Energy. It is obvious that CreateLogoDesign takes great pride in their work and rightly so. Even mounting the unit a distance that is an exact multiple of the 120 Hz wavelength from a solid reflective surface may reinforce the sound waves, causing the transformer to seem louder than it actually is. We use professional contractors to apply herbicide by utilizing different methods including foliar, stump, stem and vine applications. If trees or limbs have fallen onto power lines, we will dispatch crews to clear the vegetation from power lines and equipment. Planned maintenance is prioritized by evaluating reliability data, field conditions and other specific information. We work diligently to capture the look and feel that you always desired for your logo. Then, without connecting the load, energize the transformer. To know about this special offer, please click here. endstream endobj 2044 0 obj <>>>/Pages 2032 0 R/StructTreeRoot 707 0 R/Type/Catalog>> endobj 2045 0 obj <>/Font<>/ProcSet[/PDF/Text/ImageC]/XObject<>>>/Rotate 0/StructParents 0/Type/Page>> endobj 2046 0 obj <>stream They gave us 6 logo ideas to start with. Our objective is to promote low-growing vegetation to minimize potential electric power interruptions, which also enhances wildlife habitat. Locating a unit at the end of a long, narrow room, or in the corner of a room can cause a megaphone effect and amplify the transformer's sound. ; 4 Final files will be provided in any format. 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. 373-6, Deflection of Conductors, and referenced in Sec. To get your Company Logo developed by our experienced Logo Designers, please fill out our Order Form. We are delighted with the end result, it looks incredibly professional. 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. The harmonics resulting from nonsinusoidal currents generate additional losses and heating of the transformer coils, which reduce the transformer life expectancy. It is good practice to regularly test this type of transformer in order to determine dielectric breakdown, which affects its useful life. As stated in the Occupational Safety and Health Authority (OSHA) standards and ANSI Z133, an unqualified person should not work within 10 feet of overhead power lines with voltages below 50,000 volts. Why are you trimming or cutting down my trees? Duke Energy does not prune trees for light levels or pattern. hbbd``b` $f F3 H0i .`RZ"APqeT @ C! {& The cookie is used to store the user consent for the cookies in the category "Analytics". However, their operating principles will remain with the same. Who can request trimming or removal of a tree? stream Part 3 will cover installation procedures for liquid-filled transformers that are shipped unassembled. 0 0 There are different ways in which transformers are installed and used as part of a commercial building electrical system. * Insulation power factor, which is done at initial installation and every few years thereafter to help determine the aging process of the insulation. Otherwise, they can be installed on open walls or steel columns or above suspended ceilings. When testing a transformer for sound level, you should recognize that all transformers, when energized, produce an audible noise. We do not round trees over because it contributes to poor tree health. Analytical cookies are used to understand how visitors interact with the website. Part 2 will address installation procedures for dry- and wet-type transformers, the latter being fully assembled. To provide reliable service, Duke Energy must prune or remove trees along the power lines. Note that for MV transformers, the secondary neutral is sometimes grounded through an impedance. The Duke Energy Progress (DEP) Distribution Construction Standards are available on the My Duke Energy Contractor Portal. You should arrange for an insulation resistance test to be carried out to make certain that no windings are grounded. They typically have primary voltages higher than 600 V and secondary voltages lower than 600 V with compartments for the associated protective devices assembled in an integral tamper-resistant and weatherproof unit. For pad mount transformers with ratings 75kVA through 500kVA, a typical concrete base would be 5 1/2 by 6 1/2 ft and 10 in. fzVAm_mRJ}GoE>Mb-LBo^8p:>db[[wRI)9:K^>P[A$K)-Jc]!AwDI3rJ7aZVv0%DYxX^{{iQ]7-n%3wvg=yr Regulators get few answers from Duke about substation attacks, Attacks on substations in four states raise alarm, Duke Energy commissions Floridas first solar power plant, Duke Energy Florida builds state-of-the-art substation, Duke Energy awards $40k to RCCs substation program, Duke Energy prepares rapid response to tropical storm Elsa, Duke Energy plans to triple renewable energy production this decade, Duke Energy Uses 3-D Scanning in a Substation, Duke Energy building new transmission project in central Florida, Duke Energy to invest $36B on power projects by 2026, North Carolina to receive $13B electric grid boost, Duke Energy donates transformer to college electric program, Consumer office to propose rejection of Duke Energys $1.9 billion grid upgrade, Duke Energy plans $1.9 billion modernisation of electric grid, Failure of transformer banks at Duke Energy substation causes outage, www.transformers-magazine/privacy-policy/, www.transformers-magazine/cookies-policy/. *[L EgptA80~@GI#Q@hxMGPhMgoQ ] $ k. Our Professional Package is designed for our small business, or just-starting-out business clients. Another consideration for indoor distribution transformers is the type of load: linear or nonlinear. All Rights Reserved. This cookie is set by GDPR Cookie Consent plugin. Duke Energy Carolinas Distribution Construction Standards Reference Guide The Duke Energy Carolinas Distribution Construction Standards consist of the following documents available on However, after the non-landscaped/unmaintained area is mowed, follow-up herbicide applications are applied to the volunteer, woody vegetation that is incompatible within the rights of way. endstream endobj startxref Other factors that should be considered in selecting transformers are voltage ratings for both primary and secondary, voltage taps, efficiency, impedance value, type of cooling and temperature rise, voltage insulation class, basic impulse level, and sound level. F. Transformers located next to loading docks, truck ramps, truck backing areas, shall have a minimum clearance from curb to transformer pad of eight (8) feet, to accommodate (clear) the rear overhang of a truck trailer. PADMOUNT EQUIPMENT INSTALLED AT INTERSECTIONS The difference in impedance should not exceed 7.5%. This may include personalization of content and ads, and traffic analytics. The difference is they contain an enclosed tank with nitrogen or other dielectric gas to protect the windings. 2013-2014 | All Rights Reserved MERIT MEDIA INT. Some microprocessor-based electronic devices may not be able to withstand the voltage. Here, a transformer turns ratio indicator should be used to measure the ratio. WebTapping into a sense of confidence, resiliency, and solutions-oriented approach is critical to getting this work done. gz&E6;ZdEv;z~gx Are there any special circumstances that would cause Duke Energy to limit tree pruning to less than a specified distance on either side of the right of way centerline? Take care not to damage the base or tip it over. Jana Ganion, Sustainability and Government Affairs Director. Till date we have designed more than 5,000 business logos. [ILLUSTRATION FOR FIGURE 1 OMITTED]. Business Card, The location should not expose the transformer to possible damage from cranes, trucks, or moving equipment. Duke Energy to invest $36B on power projects by 2026. For units with ratings above 500kVA to 2500kVA, a typical concrete base would be 8 ft by 9 ft and 10 in. Clearance Rules for Distribution , 4 of 10 Clearance Rules for Distribution ; Clearance Rules for Distribution , 5 of 10 Clearance Rules for Distribution ; Clearance Requirements, 6 of 10 Often the location and the method in which a transformer is placed have much to do with the perceived sound as does the actual decibels generated. 450-12 on Terminal Wiring Space. "7>^P*#e;dEH?7"\']Ec5>\(zx94|aX7NRc6~l}(} This website uses cookies to improve your experience while you navigate through the website. Introduction, 1 of 7 , active Introduction; Instructions, 2 of 7 Instructions; Circle of Safety, 3 of 7 Circle of Safety; Overview, 4 of 7 Overview; Objectives, 5 of 7 Objectives; Section Menu, 6 of 7 Section Menu; Clearances, 7 of 7 Clearances; Lesson 1, 2 of 7 Lesson 1. The foundation should be constructed of reinforced, air entrained concrete having at least 3000 psi compressive strength at 28 days after pouring. The distance increases with voltage for all voltages equal to or higher than 50,000 volts. There are instances when a tree must be trimmed or removed outside of planned maintenance. Newer Energy Efficient (EX Type) require .5" from rear and sides to any obstruction. Createlogodesign were fantastic. YUMPU automatically turns print PDFs into web optimized ePapers that Google loves. Transmission Systems . 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. There are instances when a tree must be trimmed or removed without prior notification. Transformers change voltage levels to supply electrical loads with the voltages they require. endobj However if you are not satisfied, we refund the entire amount you paid us - no questions asked. Great work! When rollers are used on transformers without a structural base, you should use skids to distribute the stress over the base. Transformers remain a fundamental component of electrical distribution systems. <>/ExtGState<>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> Before you plant a tree or shrub, please make sure the location is out of the right of way of overhead power lines and away from underground power lines and other utilities. They can be installed where moisture or airborne contaminants exist. %PDF-1.5 % Notification may be made via door hanger, telephone call, letter, in-person contact or a combination of these methods. The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". 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. 1 A Minimum of 4 Original Drafts for your Logo. When does Duke Energy obtain permission to trim or take down a tree? For this test, apply a low-voltage (240V or 480V) to the high-voltage winding and measure the output at the low-voltage winding. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. 7. Cast-coil transformers are constructed with the primary and secondary windings encapsulated in reinforced resin. Use of alternate means of fire protection must be approved by the local code enforcement authority. You also have the option to opt-out of these cookies. We have a dedicated team of logo designers producing customized logo design solutions. it windows (first story) 10 10 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 right tree or shrub, planted in the right place, can give you years of beauty and value without the potential dangers of getting too close to power lines. You should note, though, that transformers serving large harmonic loads can produce a higher audible noise. In addition, the size of the commercial facility will determine the appropriate approach for designing the electrical distribution system for the specific application.