Alexandria VA Hospital and Campus (Pineville, LA)
ASSET was engaged by Coactint, LLC, a SDVOB, to provide all of the electrical studies, reports, data collection, and infrared scans for the Alexandria Veterans Administration facility in Pineville, Louisiana. Our scope of services included the power systems modeling using SKM PowerTools software and performing the following studies, calculations and reports:
• Short Circuit
• Protective Device Coordination
• Arc Flash Analysis
• Voltage Drop
• Protective Device Settings
The Arc Flash Study was performed in accordance with National Fire Protection Association (NFPA) 70E, Standard for Electrical Safety in the Workplace and Institute of Electrical and Electronics Engineers (IEEE) 1584, and the Guide for Performing Arc Flash Hazard Calculations. The study included all significant locations in the electrical distribution system (switchboards, switchgear, motor control centers, panelboards, busways, etc.) from the incoming utility equipment or cabling down to 208V systems where work could be performed on energized circuits. Data collection and documentation of all electrical systems 110V and above. Final submittals included a formal reporting of findings, collection data and study calculations in a comprehensive report. In addition to the services mentioned above, ASSET also provided and installed all labels as well as provided training for the VA’s personnel.
Power System Study for Naval Air Station Complex (Pensacola, FL)
Naval Facilities Engineering Command (NAVFAC) requested that Gulf Power Company (GPC) perform power system studies for its Naval Air Station Complex in Pensacola comprised of NAS Pensacola, Corry, and the Hospital Complex. In turn, GPC contracted with ASSET Engineering to perform the technical work scopes required in NAVFAC’s Specification Section 260575.0025. This work consisted of two elements: (1) a field inventory of the new and changed equipment in the electrical system and update of the Utility Inventory and Risk Assessment (UIRA) data base (for items found and not listed), and (2) an update of the electrical power system model and preparation of new studies.
ASSET with NAVFAC performed a comparison of the SKM model and the URIA Database Spreadsheet to the provided single line diagrams to identify deficiencies which had to be inventoried. ASSET developed the plan to collect electrical system data for the SKM model and to collect limited data for URIA Database Spreadsheet. During the field inventory, ASSET performed an infrared survey along overhead lines, at connection points (mechanical tap on a line or connection to a switch for example), switchgear and all transformers to pinpoint potential points of failure.
• Short circuit study of the maximum fault current case to document Symmetrical and Asymmetrical Fault Current levels throughout the complex and document equipment bus bracing and interrupting ratings
• Load Flow Study (down to primary distribution transformer secondary voltage level) to power flow throughout the complex during normal operating conditions to confirm transformer capacity, conductor ampacity, and voltage drop are with acceptable limits
• Coordination Study and Protective Device Coordination to document current and proposed settings to provide for selectivity. Settings changes to microprocessor based relays and trip units will be documented in an easy to understand format to detail work to be completed in the field
• Arc Flash Hazard Analysis per NFPA 70E and IEEE 1584 for normal and one alternate system configuration to determine the incident energy at equipment locations across the system
• Infrared Study including prioritized list of equipment needing attention noting location, limited scope of work and cost estimates and images captured for documentation
Electrical System Studies listed above were performed after primary load currents and transformer secondary voltage, current, and power measurements were made. Noncontact amp-probe current meters with hotsticks were used to measure currents on overhead power lines and in pad mounted junction vaults and transformers as identified by selection of critical nodes. Battery operated power recorders using rope-type current transformers and voltage clips were placed in secondary compartments of transformers (approximately 10 units per NAVFAC request). Recordings were made for 48 hours in an effort to capture values for two consecutive summer electrical peak days. Ten recorders were used, with five recorders moved to new locations each day until all load measurements had been captured and documented for later use in the SKM load flow study.
Hurlburt Field AFB, Power Quality Study (Mary Esther, FL)
Gulf Power engaged ASSET Engineering to perform the technical scope for replacing an existing pad-mounted medium voltage multi-step capacitor bank at Hurlburts’ main substation. Harmonics analysis was required to determine the values associated with the design and operation of the filtered capacitor bank. ASSET Engineering provided a Harmonics Study and Analysis, inclusive of collecting the field measurements required in the specification of the capacitor bank. The following project tasks and deliverables represented our scope:
• Update an EASY POWER model with the GPC fault current, transformer, cable, and existing capacitor bank information, and measured fundamental and harmonic currents on each of the four (4) 12 kV Feeders and the Main Bus.
• Perform harmonic study in order to specify new capacitor units taking into account switching for Power Factor Correction.
• Narrative findings summary for the harmonics studies, and proposed component modifications.
• Updated Easy Power model for use in Filter Evaluation
• Report documenting the findings of:
o Harmonic analysis of the station in conjunction with GPC provided fault current levels and ASSET measured fundamental and harmonic currents on each feeder and the main substation bus, and
o Capacitor bank rating per stage along with component specifications to account for present and future Gulf Power fault current contributions and present and anticipated future base loads including their harmonic content.