ARC Flash Study - Pittsburgh VAMC Facilities

Scope of Work shall be identified on the diagrams. For Final Submission: Provide four hard copies and four electronic copies (compact disc) of the electrical system study (including data files). One original document of Final Submission shall be sent to Chief Engineer/COR at VAPHS and shall include: A completed Report, including all corrected data from the 60% and 90% submittals and the coordination curves shall be printed in color. Responses to the 60% and 90% submission comments from CFM, VHA, VAPHS, and Peer Review, including annotations and response. Electronic copy (CD) of the entire report including all SKM data, AutoCAD, Word, Excel files and PDF. Color photos that show devices listed on the deficiency report. Arc Flash Hazard Warning labels compliant with requirements of latest NFPA 70E. NOTE: Arc Flash Hazard Warning labels are to be installed on each corresponding device. Prior/Existing Labels are to be completely removed. Provide final report with stamp and signature by a Licensed Professional Electrical Engineer. The other three (3) copies of the Final Submission shall be sent to VAPHS. Those copies shall include the followings: The Executive Summary. Fault Current Evaluation Results Protective Device Coordination Analysis and Recommendations. Protective Device Settings. Cost Estimates. Responses to the 60% and 90% submission comments from VAPHS, and Peer Review, including annotations and response. One-line diagrams for primary distribution system on 11 x17". Electronic copies (CD) of the entire report including all SKM data, AutoCAD, Word, Excel files and PDF formats. Provide final report with stamped and signed by a Licensed Professional Electrical Engineer. SPECIFIC SCOPE The Contractor shall prepare a complete Short Circuit and Coordination Study including voltage drop calculations on the entire electrical system/s (both normal and emergency) at each VAPHS facility location. It shall begin at the incoming utility electrical service (for the normal system) and at the emergency generators (for the emergency system) and continue through to each branch circuit panelboard, motor control center or motor control panel in each building. The study shall include a system one-line diagram; Short Circuit and ground fault analysis, protective coordination plots, voltage drop calculations and the following for each building: One Line Diagrams: The one-line diagrams shall show the schematic wiring of the electrical distribution system for each building. Include all electrical equipment and wiring protected by the over current devices. Also show on the one-line diagrams the following specific information: Calculated Short Circuit values at each bus. Breaker and fuse ratings. Transformer kVA, voltage ratings and wiring connections. Voltage at each bus. Identification of each bus. Conduit material, feeder sizes and lengths. Generator kW and voltage ratings. Room Number for each electrical equipment including, but not limited to, the panelboard, disconnect, and transformer, etc. Ground Resistance Analysis: A concise qualitative description (not to exceed one (1) page of narrative) describing the overall condition of the facility ground resistance shall be provided. Any violations of NEC or other abnormalities (high ground resistance, damaged conductors or electrodes, harmonics, etc.) warranting further detailed study shall be highlighted. Analysis of the facility ground resistance shall be based upon: Facility Ground Resistance Test report (provided by VAPHS, if available) Visual inspection of visible ground system components (made during site investigation). Include photographs in Appendices. Interviews with VAPHS engineering staff Other data on ground system made available by the VAPHS. Short Circuit Study: Systematically calculate the fault impedance to determine the available Short Circuit and ground fault currents at each bus. Incorporate the motor contribution in determining the momentary and interrupting ratings of the protective devices. Motors less than 25 HP may be grouped together. The study shall be calculated by using SKM software. Pertinent data and the rationale employed in developing the calculations shall be incorporated in the introductory remarks of the study. Use actual conductor impedances if known. If unknown, use typical conductor impedances based on IEEE Standard 141-1993. Transformer design impedances shall be used when test impedances are not available. Provide the following: Calculation methods and assumptions Selected base per unit quantities One-line diagram of the system being evaluated Source impedance data, including electric utility system and motor fault contribution characteristics Tabulations of calculated quantities Results, conclusions, and recommendations. Calculate short-circuit momentary and interrupting duties for a three-phase bolted fault at each: Electric utility s supply termination point Incoming switchgear Unit substation primary and secondary terminals Low voltage switchgear Motor control centers Standby generators and automatic transfer switches Branch circuit panelboards Machine control panels Bus Ducts Other significant locations throughout the system. For grounded systems, provide a bolted line-to-ground fault current study for areas as defined for the three-phase bolted fault short-circuit study. Protective Device Evaluation: Evaluate equipment and protective devices and compare to Short Circuit Ratings. Adequacy of switchgear, motor control centers, and panelboard bus bars to withstand short-circuit stresses. Notify Owner in writing, of existing, circuit protective devices improperly rated for the calculated available fault current. Present the data determined by the Short Circuit study in a table format, include the following: Transformer kVA and voltage ratings, percent impedance, X/R ratios and wiring connections. Generator kW and voltage ratings. Conduit material, feeder sizes, length and X/R ratios. Device identification (Manufacturer, Catalog No. and Device Curve No. and ID) Operating voltage. Protective device. Device rating. Calculated Short Circuit current. Hazard-Risk category at each piece of equipment for the worst-case fault condition. Arc Flash Hazard Analysis: The arc flash hazard analysis shall be performed according to the IEEE Std. 1584-2018. The IEEE Std 1584-2018 provides a new mathematical model and calculation procedure, which is more comprehensive, accurate, and complex than the IEEE Std 1584-2002. The SKM modeling must consider the equipment configuration, whether the buss/conductor is horizontal or vertical. Also, the equipment s actual dimensions need to be accounted for to increase the calculation accuracy. The flash protection boundary and the Incident Energy shall be calculated at all equipment locations referenced in IV. The Arc-Flash Hazard Analysis shall include all significant locations in 480 volt and 208-volt systems fed from transformers equal to or greater than 125 kVA where work could be performed on energized parts. Safe working distances shall be based upon the calculated arc flash boundary considering Incident Energy of 1.2 cal/cm2. When appropriate, the Short Circuit calculations and the clearing times of the phase overcurrent devices will be retrieved from the Short-Circuit and Coordination Study model. Ground overcurrent relays should not be taken into consideration when determining the clearing time when performing Incident Energy calculations The short-circuit calculations and the corresponding Incident Energy calculations for multiple system scenarios shall be compared and the greatest Incident Energy must be uniquely reported for each equipment location. Calculations must be performed to represent the maximum and minimum contributions of fault current magnitude for all normal and emergency operating conditions. The minimum calculation will assume that the utility contribution is at a minimum and will assume a minimum motor contribution (all motors off). Conversely, the maximum calculation will assume a maximum contribution from the utility and will assume the maximum amount of motors to be operating. Calculations shall take into consideration the parallel operation of synchronous generators with the electric utility, where applicable. The Incident Energy calculations must consider the accumulation of energy over time when performing arc flash calculations on buses with multiple sources. Iterative calculations must take into account the changing current contributions, as the sources are interrupted or decremented with time. Fault contribution from motors and generators should be decremented as follows: Fault contribution from induction motors should not be considered beyond 3-5 cycles. Fault contribution from synchronous motors and generators should be decayed to match the actual decrement of each as closely as possible (e.g., contributions from permanent magnet generators will typically decay from 10 per unit to 3 per unit after 10 cycles). Each equipment location with a separately enclosed main device (where there is adequate separation between the line side terminals of the main protective device and the work location), calculations for Incident Energy and flash protection boundary shall include both the line and load side of the main breaker. When performing Incident Energy calculations on the line side of a main breaker (as required per above), the line side and load side contributions must be included in the fault calculation. Mis-coordination should be checked amongst all devices within the branch containing the immediate protective device upstream of the calculation location and the calculation should utilize the fastest device to compute the Incident Energy for the corresponding location. Arc Flash calculations shall be based on actual overcurrent protective device clearing time. Where it is not physically possible to move outside of the flash protection boundary in less than 2 seconds during an arc flash event, a maximum clearing time based on the specific location shall be utilized. Arc Flash Labeling: Contractor shall produce and install, the Arc Flash Labeling, to the VAPHS according to the number of distribution devices that are shown on the one-line diagram in accordance with NFPA 70 (NEC) and NFPA 70E. Labels shall be 4 x 6 (nominal) printed on industrial quality, adhesive backed vinyl. Danger labels shall have pre-printed headers in red; "Danger" labels shall be provided for equipment/devices having incident energy greater than or equal to 40 cal/Cm2; Warning labels shall have pre-printed headers in orange. "Warning" labels shall be provided for equipment/devices having incident energy less than 40 cal/cm2. Electrical equipment shall be labeled IAW NFPA 70, Articles 110.16 & 100.21(B) and NFPA70E, Article 130.5. The arc flash hazard analysis to determine the Arc Flash Protection Boundary for each label shall be calculated IAW NFPA 70E Paragraph 130.5 (B). Nominal system voltage Arc flash boundary At least one of the following: Available incident energy and the corresponding working distance, or the arc flash PPE category in Table 130.7(C)(15)(A)(b) or Table 130.7(C)(15)(B) for the equipment, but not both Minimum arc rating of clothing Site-specific level of PPE In addition to the requirements of NFPA 70 and 70E, each customized label shall identify the corresponding piece of electrical equipment, by Panelboard or device identifier and Building and room number. Generic labels do not require equipment and building identifiers. Arc flash labels shall be provided in the following manner and all labels shall be based on recommended overcurrent device settings. For each 600, 480 and applicable 208-volt panelboard, one arc flash label shall be provided. For each motor control center, one arc flash label shall be provided. For each low voltage switchboard, one arc flash label shall be provided. For each Switchgear, one flash label shall be provided. For medium voltage switches one arc flash label shall be provided For each machine control panel, one arc flash label shall be provided. For each bus duct plug, one arc flash label shall be provided. For each compartment of the transformer, one arc flash label shall be provided. Protective Device Coordination Study: Prepare the coordination curves to determine the required settings of protective devices to assure selective coordination. Graphically illustrate (using log paper) that adequate time separation exists between series devices, including the utility company upstream device. Plot the specific Time Current Characteristics (TCC) of each device in the electrical system as follows: Provide TCC curve down to the last branch-circuit panelboard (regardless the protective device is an adjustable or fixed device) in the three-branches of the Essential Electrical System (EES). Provide TCC curve down to the last adjustable device (stop after the first fixed device) in the Normal System but at the minimum two-level curves from each of the building Service Entrance switchgear/switchboard shall be provided. The following specific information shall also be shown on the coordination curves at each level of power distribution system: Device identification (including Manufacturer, Catalog Number, and Device Curve Number and ID) Voltage and current ratio for curves. 3 phase and 1 phase ANSI damage points for each transformer. No damage, melting, and clearing curves for fuses. Cable damage curves. Transformer inrush points. Maximum Short Circuit cutoff point. Excerpts from one-line diagram reflecting the protective devices modeled on each curve. This excerpt may be inserted onto a corner (typically top right-hand) of the curve print out or may be on the preceding facing page for ease of reference. Provide explanation, analysis, and recommendation to achieve better coordination. The analysis for recommended curve of a particular device shall be put right after the existing curve in the report for comparison. Develop a table to summarize the settings selected for the protective devices. Include all medium voltage devices in the table, as well as all low voltage devices which require modification, showing the following data: Device identification. Relay CT ratios, tap, time dial, and instantaneous pickup. Circuit breaker sensor rating, long time, short time, and instantaneous settings, and time bands. Fuse rating and type. Ground fault pickup and time delay. Voltage Drop Calculations: Provide voltage drop calculations for all three-phase branch and feeder circuits. Show calculated voltages at each bus and voltage drops on each feeder. Calculations shall be based on the maximum values of kVA, kW, kvar, power factor and amperes for each power circuit. For branch circuit level, use 80% of nameplate rating. For incoming service and distribution level, use 50% of the nameplate rating or actual maximum peak demand load collected in the field if it is available. Provide tabular information showing the sizes of all cables, transformers, and other circuit data. Provide a system one-line diagram which clearly identifies individual equipment busses, bus numbers, cable and bus connections and other circuit information. Provide a separate section or tables which provide an evaluation of the calculated voltage drops with recommendations for improvements where voltage drops exceed the allowable NEC limits. Emergency Power System Analysis: First, a narrative describing the existing emergency power system(s) at the VAPHS location shall be provided, to include a description of each emergency generator, physical location, size (kW and ampacity), voltage, configuration (phase, wire), circuit number, age, and overall condition. A summary of the average loading on each generator (based on data provided by the VAPHS) shall be provided and then compared to projected future loads (A-E shall develop load projections from discussing forecast projects and growth with VAPHS engineering staff), A-E shall provide a qualitative narrative on the suitability of the existing generators to meet projected future loads. If existing Emergency Power System, including generators, is not adequate to meet either current or future demands, recommendations shall be provided in the study. A-E shall summarize the findings in tabular form reflecting (as a minimum), the VAPHS peak demand, average demand, transformer capacity and total generator capacity. Analysis and Recommendations: For all electrical equipment, determine if adequate code clearances exist. Note cases by site, building and specific equipment that do not include adequate code clearances and provide a cost estimate to resolve the problems. Provide information in table format. Determine if ground fault protection exists where required by NFPA 70 Articles 215 and 517. Note all cases where this condition exists and provide cost estimates to correct. Provide information in table format. For all automatic transfer switches, determine if the correct 3-pole or 4-pole switches are used. Where ground fault protection is used on the normal feed to the switch, determine if the switch is correctly wired. Note all cases where this condition exists and provide cost estimates to correct. Provide information in table format. Note any use of cable limiters and provide recommendations to avoid any single phasing conditions. Note all cases where this condition exists and provide cost estimates to correct. Provide information in table format. On the medium voltage switchgear, where undervoltage relays (27) are used, determine whether all 3 phases are monitored or only 2 phases are monitored. For those locations where only 2 phases are monitored, provide a cost estimate for providing adequate protection for all 3 phases. Analyze the short circuit calculations and highlight any equipment that is determined to be underrated. Provide recommendations to protect the underrated equipment effectively. After developing the coordination curves, highlight areas lacking coordination. Present a technical evaluation with a discussion of the logical compromises for best coordination. Assess the equipment condition using grading method in term of A, B, C, D and F. Grade A - Like New Condition. Majority of useful life span remains. "Excellent" Grade B - Good Condition. Over half of useful life span remains. "Good" Grade C - Average Condition. Less than half of useful life span remains. "Average" or "Fair" or C+ "Above Average" Grade C - Workable Condition. May be past assigned useful life, but still working. "Keep an eye on it" Grade D - Poor Condition. Past assigned useful life. Failure is not critical. Poor" or "Problematic" Grade F - Critical Condition. Needs immediate attention. Failing" or "Critical" Protective Device Settings: For all adjustable and fixed protective devices, provide tables to show existing settings and new settings where changes are recommended for proper protection. If adjustments will not provide adequate protection, provide recommendations to update or replace the existing underrated equipment and include cost estimates to accomplish the necessary corrections. Provide table in Excel format to show ONLY the devices that require that their settings need adjustment. Cost Estimates: For each building included in the electrical study at each VAPHS location, where recommendations are to replace or update the existing electrical system to provide adequate protection, provide estimated construction costs for the necessary work. Total costs for each building shall be included in addition to an itemized breakdown to identify major items requiring replacement or upgrading. Costs shall be totaled for each VAPHS location. Cost estimates shall not include adjustments for anticipated phasing, shutdowns or overtime work. An electronic copy of the Cost Estimate in an editable MS Excel spreadsheet shall be included in the submission of the final, corrected study. The Excel spreadsheet will be used to track mitigation efforts. SCHEDULE Site survey work shall begin immediately and be coordinated with VAPHS after awarding of the contract. All final reports shall be completed, submitted, and approved within 360 calendar days after the Notice to Proceed. The study will provide an independent and documented overview of the entire electrical infrastructure conditions in each building at each VAPHS location. The VAPHS locations shall be contacted at least three (3) weeks in advance of the site visit to allow ample time for the VAPHS location to arrange the staffs and prepare the necessary documents. Each facility electrical study shall take no longer than 360 calendar days. Draft final reports shall be submitted 30 days before the submission of the complete final report. The draft final report will be reviewed by the government with comments, edits and corrections provided to the contractor within three weeks after receipt of the draft final report. The contractor shall provide a schedule for the staggered start and staggered submission/completion (at least 15 days between submissions) of these awarded studies over a time period of 360 calendar days. Draft final reports (90% submission) shall be submitted 30 days before the submission of the complete final report. The draft final report will be reviewed by the government with comments, edits and corrections provided to the contractor within three weeks after receipt of the draft final report. Contractor shall submit a tentative delivery schedule to VAPHS for approval prior to any work.

Architectural, New Construction.