duke energy transformer clearance requirements

This cookie is set by GDPR Cookie Consent plugin. All products used by Duke Energy are registered by the Environmental Protection Agency and approved by appropriate state agencies. A right of way is a type of easement or agreement that grants a utility the right to use, access or transit a piece of property. He is a registered professional engineer with more than 29 years of experience in electrical engineering, project management, building design, and construction. If this does not happen, de-energize the transformer and contact the manufacturer. Why are you trimming or cutting down my trees? The transformer is equal to or less than its rated kVA and rated voltage. The average temperature of the cooling air during a 24-hour period is 86 F. The temperature of the cooling air at no time exceeds 104 F. Selecting Transformer selection starts with the kVA rating required to supply the loads connected in the electrical system. hkO0ibv*JmG[$ ]]> Selecting, sizing transformers for commercial buildings, By using this website, you agree to our use of cookies. thick with chamfered edges on top of the base and footings extending 20 in. These considerations should be taken into account, as well as the use of sound absorbing materials on walls (for low frequency sound) and vibration isolation pads under the unit. When specifying a transformer to be operated in parallel with existing units, all these parameters should be discussed with the transformer manufacturer. 0 Such stress could cause a bushing to crack or a connection to fail. When is tree trimming considered an emergency? It's recommended that all conducted tests comply with applicable ANSI/IEEE and NEMA standards. WebThe Duke Energy Renewables Facility this position would report to is located in Mercedes, Texas. For this test, apply a low-voltage (240V or 480V) to the high-voltage winding and measure the output at the low-voltage winding. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. And its important that you follow current NEC practice and applicable local codes. You can have big-business results at a "business-on-a-budget" price! We really liked two of them, and asked him to amalgamate them. This should be done at some safe access point near or at the load. Representative torque requirements for making connections using steel nuts/bolts are shown in Table 1, on page 42. Our goal is to provide professional logo design at an affordable price. Newer Energy Efficient (EX Type) require .5" from rear and sides to any obstruction. What fantastic professionals to work with. 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. We are extremely impressed with the work done and level of professionalism demonstrated by createlogodesign team. When your transformer arrives on site, various procedures should be carried out to assure successful operation. All windings should be checked for continuity. You should arrange for an insulation resistance test to be carried out to make certain that no windings are grounded. However, for low-voltage (600V and below) transformers, this is not practical. When the load-side voltage is low, tap connections below 100% of line voltage must be used to raise the load voltage. When viewing transformer product literature, you'll probably find that one manufacturer's units will have differences from that of a competing manufacturer. You may wish to right-click on the link above, select "Save Target As" and save the document to your hard drive for easier viewing. WebIntroduction, 1 of 7 Introduction. ;w]S9 V?O|H?&V+f[^ c#7b0#M>*. Adequate surrounding air space must be maintained for the required transformer "heat loss" ventilation. Sound levels associated with certain kVA ratings will vary depending upon the type of transformer and manufacturer. They were great at following our directions to the letter, while adding their own creative flair. The tap setting should also be verified for the proper voltage. The cables you install must be kept as far away as possible from coils and top blades. The MIA South Terminal expansion was designed with about 50 transformers with similar intent as the stadiums but a more diverse group of loads for the 208 Y/120 V 3-phase, 4-wire system, which also included lighting loads, signage, telecommunication, security systems, and other loads part of this building project (Figure 1). Occasionally, a property owner will make the decision to conduct trimming or removals on their own or hire a third party. Never attempt to check the output voltage at the transformer. 1&Ub64#C #") "7KWpzJz1YeHB.r32Az{`gC~;jiV[Ceb*1rAz96lnA|3$ They were very attentive to our needs, very detailed with their work, and met the needs of our timetable. This cookie is set by GDPR Cookie Consent plugin. All Rights Reserved. Before your transformer is scheduled to be shipped to its designated site, it's important that you coordinate with the manufacturer what acceptance tests should be carried out. Duke Energy does not prune trees for light levels or pattern. The 18,688-seat FIU football stadium was designed with about 12 transformers as part of the electrical system distribution in order to supply general-use receptacles, small motors, and other loads in the stadium building structure and the attached field house building. Duke Energy contractors have been trained on the proper, safe and environmentally responsible techniques of managing plant growth. Serious injuries, and even fatalities, have occurred when unqualified individuals perform this type of work without the assistance of qualified professionals. The Duke Energy Progress (DEP) Distribution Construction Standards are available on the My Duke Energy Contractor Portal. Great work! When people identify downed lines or trees touching power lines and act wisely, it minimizes the risk from trees contacting power lines. The installation of conductors should be performed only by personnel qualified and experienced in high-voltage equipment. They supply the required incoming electrical service to the buildings. This does not apply to bottom ventilation openings. 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. 847 0 obj <>stream Before specifying any additional tests, you should contact the manufacturer to find out what data it has accumulated from testing essentially duplicate units. Great service. ; 3 Then we will refine your Logo until you are 110 % satisfied! Check all of the tap jumpers for proper location and for tightness. If you have some doubt as to the load capability of the unit, contact the manufacturer. We do not round trees over because it contributes to poor tree health. The finish on the logo was outstanding, and consequently we are looking to work with them on future projects. If an imminent threat to Duke Energy power lines exists, we prioritize and schedule the work based on the severity of the situation. 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. Standard transformer tests performed for each unit include the following: * Polarity for single- and 3-phase units (because single-phase transformers are sometimes connected in parallel and sometimes in a 3-phase bank); * Phase relationship for 3-phase units (important when two or more transformers are operated in parallel); * Excitation current, which relates to efficiency and verifies that core design is correct; * No-load core loss, which also relates to efficiency and correct core design; * Resistance, for calculating winding temperature and [I.sup.2]R component of winding losses (usually not required on 600V class units); * Impedance (via short circuit testing), which provides information needed for breaker and/or fuse sizing and interrupting rating and for coordinating relaying schemes; * Load loss, which again directly relates to the transformer's efficiency; * Regulation, which determines voltage drop when load is applied; and. 837 0 obj <>/Filter/FlateDecode/ID[<628CD90D08ABAB4FB038EF4B9C9C7E56>]/Index[820 28]/Info 819 0 R/Length 84/Prev 192869/Root 821 0 R/Size 848/Type/XRef/W[1 2 1]>>stream Transformers change voltage levels to supply electrical loads with the voltages they require. When rollers are used on transformers without a structural base, you should use skids to distribute the stress over the base. 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. How often does Duke Energy trim or cut trees? However if you are not satisfied, we refund the entire amount you paid us - no questions asked. The development was easy because Steffi provided unlimited revisions, so we went through a series of small changes until we got a final. Reproduction, Sealed dry-type transformers are similar to dry type in most of their characteristics. If this isn't possible, you first should contact the manufacturer to explore other options. Who should trim or cut trees around power lines? (If the power transformer has CT circuits, they should be closed.) 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. In the presence of a magnetic field, the core laminations elongate and contract. When speaking to consulting engineers on this topic, we've found that they recommend the cable be sized for the transformer's nameplate rating. Trees can disrupt power in a number of ways. There are additional tests that may be applicable, depending upon how and where the transformer will be used. Analytical cookies are used to understand how visitors interact with the website. Does Duke Energy manage vegetation that interferes with the light levels or pattern of light from streetlights and security lights? In addition, the size of the commercial facility will determine the appropriate approach for designing the electrical distribution system for the specific application. We use professional contractors to apply herbicide by utilizing different methods including foliar, stump, stem and vine applications. Review our, Ralph Baeza, PE, LEED AP, TLC Engineering for Architecture, Miami, Offices codes and standards change, accommodating new work styles, Codes, standards cause health care building design model to shift, Manufacturing and industrial building codes and standards trends, Codes and standards drive trends, changes in data center design, Technology drives K-12 school changes, while meeting codes and standards, Consulting-Specifying Engineer most-viewed codes and standards articles in 2022. We offer a 100% Satisfaction Guarantee. ; 3 Then we will refine your Logo until you are 110 % satisfied! 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. For transformers placed outside that are 2000kVA and above, you may wish to have the soil examined. Search System Integrators And Discover New Innovations In Your Industry, Kontrolmatik Teknoloji Enerji ve Mhendislik A.. To simplify installation, you should request from the manufacturer a simplified outline drawing of the transformer. You will not be disappointed, i promise. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc. S=9X^&>``AT#l2} ppC_H. How do I request tree trimming or tree removal by Duke Energy? I was so impressed with the finished result that I've asked them to undertake future work. There are NEMA standards for transformer sound and depending upon the kVA rating of a unit, the sound it produces must be under a certain decibel level. This was our second project and I knew exactly who I wanted to work with. 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. September 14, 2022. Caution is required when operating in parallel. Contact Duke Energy to request a representative to make evaluations of your request. WebPer 450.27 of the NEC; Combustible material, combustible buildings, and parts of buildings, fire escapes, and door and window openings shall be safeguarded from fires originating in oil-insulated transformers installed on roofs, attached to or adjacent to a building or combustible material. 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. n"fyuAf[vz}:L3h0vjB)ta=T5MFKV3!YyeQ.\A?|1a/9 yQQ1KR8N:@Q.LCmGwP72juW*QW_8"DyP3(\gjQ8qCZA{xGW*-EETOzk~h+,I`=p 3 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. This may call for compromises regarding the length of the conductors going to and/or from the transformer. Electrical Service Requirements (ESR) Current as of October 28, 2022 The ESR Manual provides guidance and instructions pertaining to electrical service connections. 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. 2043 0 obj <> endobj 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. They have clearly demonstrated their understanding of design while also meeting our needs. The greater the differences in these parameters, the greater the magnitude of the circulating current. See my site logo at. The cookie is used to store the user consent for the cookies in the category "Performance". Transmission Systems . Roles and Responsibilities Associated with Clearances, 1 of 8 the local authority having jurisdiction (ahj) may have requirements that are more stringent. Our new online service request capability walks you through the process, auto-populates saved information from your profile, and gives you more control over when and Is Duke Energy responsible for cleanup after trimming trees or weather events? All rights reserved. 4, on page 44, and when all enclosure hardware is tightened so panels do not vibrate. 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. 373-6, Deflection of Conductors, and referenced in Sec. 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. 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. Our understanding of their general characteristics will allow the designer and end user to make the proper selection for the electrical system application. 3-Phase Padmount Transformer Concrete Foundation - Duke Energy.