Specifications for Power System Analysis

PART 7 - EXECUTION

1. Gather and tabulate the following input data to support the power systems study:
   1. Product Data for overcurrent protective devices involved in overcurrent protective device coordination studies.  Use equipment designation tags that are consistent with electrical distribution system diagrams, overcurrent protective device submittals, input and output data, and recommended device settings.
   2. Maximum fault contribution or Impedance of utility service entrance
   3. Electrical Distribution System Diagram:  In hard-copy and electronic-copy formats, showing the following:
      1. Circuit-breaker and fuse-current ratings and types
      2. Generator kilovolt amperes, size, voltage, and source impedance
      3. Cables: Indicate conduit material, sizes of conductors, conductor material, insulation, and length
      4. Motor horsepower and code letter designation according to NEMA MG 1
   4. Data sheets to supplement electrical distribution system diagram, cross-referenced with tag numbers on diagram, showing the following:
      1. Special load considerations, including starting inrush currents and frequent starting and stopping
      2. Transformer characteristics, including primary protective device, magnetic inrush current, and overload capability
      3. Motor full-load current, locked rotor current, service factor, starting time, type of start, and thermal-damage curve
      4. Generator thermal-damage curve
      5. Ratings, types, and settings of utility company's overcurrent protective devices
      6. Special overcurrent protective device settings or types stipulated by utility company
      7. Time-current-characteristic curves of devices indicated to be coordinated
      8. Manufacturer, frame size, interrupting rating in amperes rms symmetrical, ampere or current sensor rating, long-time adjustment range, short-time adjustment range, and instantaneous adjustment range for circuit breakers
      9. Manufacturer and type, ampere-tap adjustment range, time-delay adjustment range, instantaneous attachment adjustment range, and current transformer ratio for overcurrent relays
      10. Panelboards, switchboards, motor-control center ampacity, and interrupting rating in amperes rms symmetrical
2. Software shall have the ability to utilize typical data such as %Z, X/R ratios for transformers, etc. in case these values cannot be ascertained from existing documentation and/or field data collection.
3. Various system operating configurations of the system including status of switching devices and load status (continuous, intermittent, spare), etc. shall be modeled as part of the project database using a configuration management tool.
4. Study related scenarios including data revisions, engineering properties, study solution parameters & network topology shall be setup. In the event of system changes, these scenarios may be utilized by Company at a later date to re-run the studies.

1. Load flow study should be performed to evaluate the system’s capability to adequately supply the connected load and prevent overloading of equipment.
2. Compare equipment (transformers, cables, breakers, fuses) operating values against manufacturer’s specified maximum capability ratings whenever available.
3. Provide a computer generated Alert View list/report which lists all equipment that is critically overloaded.
4. Load Flow study should consider various operating conditions (scenarios) such as; maximum loading, minimum loading and normal loading.
5. Provide a computer generated load flow analysis report that simultaneously provides power flow results between the different scenarios being evaluated.

1. Software shall have the ability to generate a single Fault Current report that includes the Device Duty Evaluation as per ANSI/IEEE C37 standards.
2. Calculate the maximum available short circuit current in amperes rms symmetrical at circuit-breaker positions of the electrical power distribution system.  The calculation shall be for a current immediately after initiation and for a three-phase bolted short circuit at each of the following:
   1. Switchgear, switchboard , busways, bus duct
   2. Distribution panelboard
   3. Branch circuit panelboard
3. Study electrical distribution system from normal and alternate power sources throughout electrical distribution system for Project.  Include studies of system-switching configurations and alternate operations that could result in maximum fault conditions
4. Calculate momentary and interrupting duties on the basis of maximum available fault current at each location:
   1. Electric utility’s supply termination point
   2. Incoming switchgear
   3. Unit substation primary and secondary terminals
   4. Low voltage switchgear
   5. Motor control centers
   6. Standby generators and automatic transfer switches
   7. Branch circuit panelboards
   8. Other significant locations throughout the system
5. Calculations to verify interrupting ratings of overcurrent protective devices shall comply with IEEE 241 and IEEE 242
6. Fault Study Report shall include
   1. EShow calculated X/R ratios and equipment interrupting rating (1/2-cycle) fault currents on electrical distribution system diagram.
   2. Calculation methods and assumptions including any adjustments used when considering resistance and impedance tolerances.
   3. One-line diagram of the system being evaluated with available fault at each bus
   4. Typical calculations
   5. Comparison of Short Circuit results from different scenarios in a single display
   6. Results, conclusions, and recommendations
7. Device Duty Equipment Evaluation Report:
   1. For 600-V overcurrent protective devices, ensure that interrupting ratings are equal to or higher than calculated 1/2-cycle symmetrical fault current.
   2. For devices and equipment rated for asymmetrical fault current, apply multiplication factors listed in the standards to 1/2-cycle symmetrical fault current.
   3. Verify adequacy of phase conductors at maximum three-phase bolted fault currents; verify adequacy of equipment grounding conductors and grounding electrode conductors at maximum ground-fault currents. Ensure that short circuit withstand ratings are equal to or higher than calculated 1/2-cycle symmetrical fault current.
   4. Software shall have the ability to generate a single Fault Current report that includes the Device Duty Evaluation as per ANSI/IEEE C37 standards
8. Software shall utilize data revisions to track system data changes such as “As Found” and “Recommended” settings.

1. Perform coordination study using approved computer software program.  Prepare a written report using results of fault-current study.  Comply with IEEE 399.
   1. Calculate the maximum and minimum 1/2-cycle short circuit currents
   2. Calculate the maximum and minimum interrupting duty (5 cycles to 2 seconds) short circuit currents
   3. Calculate the maximum and minimum ground fault currents
2. Software shall be capable of plotting and diagramming time-current-characteristic curves as part of its output. Computer software program shall report device settings and ratings of all overcurrent protective devices and shall demonstrate selective coordination by computer-generated, time-current coordination plots.
3. Software shall be able to perform a Sequence of Operation that evaluates, verifies, and confirms the operation and selectivity of the protective devices for various types of faults directly from the one-line diagram and via normalized Time Current Characteristic Curve views.
4. Generate a report that highlights detected violations and concerns of equipment protection and device coordination:
   1. List possible corrections and adjustments of protective device settings
   2. Provide violation descriptions with each detection provided
5. Comply with IEEE 241 recommendations for fault currents and time intervals.
6. Conductor Protection:  Protect cables against damage from fault currents according to ICEA P-32-382, ICEA P-45-482, and conductor melting curves in IEEE 242.  Demonstrate that equipment withstands the maximum short circuit  current for a time equivalent to the tripping time of the primary relay protection or total clearing time of the fuse.  To determine temperatures that damage insulation, use curves from cable manufacturers or from listed standards indicating conductor size and short circuit  current.
7. Transformer Protection: Protect transformers against damage from through fault currents according to ANSI C57.109, IEEE C57.12.00, IEEE 242
8. Low-Voltage Circuit Breakers: IEEE 1015 and IEEE C37.20.1
9. Coordination Study Report:  Prepare a written report indicating the following results of coordination study:
   1. Computer generated Overcurrent Protective Devices report must include:
      1. Device tag
      2. Current transformer ratios; and tap, time-dial, and instantaneous-pickup values
      3. Circuit breaker sensor rating; and long-time, short-time, and instantaneous settings
      4. Fuse current rating and type
      5. Ground fault relay-pickup and time-delay settings
   2. Coordination Curves: Prepared to determine settings of overcurrent protective devices to achieve selective coordination. Graphically illustrate that adequate time separation exists between devices installed in series, including power utility company's upstream devices.  Prepare separate sets of curves for the switching schemes and for emergency periods where the power source is local generation.  Show the following information:
      1. Device tag
      2. Voltage and current ratio for curves
      3. Three-phase and single-phase damage points for each transformer
      4. Melting and clearing curves for fuses
      5. Cable damage curves
      6. Transformer inrush points
      7. Maximum fault-current cutoff point
10. Provide a computer generated data sheet report for setting of overcurrent protective devices
11. Software shall utilize data revisions to track system data changes such as “As Found” and “Recommended” settings.

1. Perform Arc Flash analysis according to the IEEE 1584 guidelines and equations presented in NFPA 70E-2015, Annex D. Analysis shall be performed in conjunction with Short Circuit analysis and Protective Device Time-Current Coordination analysis.
2. Incident Energy and Flash protection boundary shall be calculated at all location where energized work could be performed such as switchboards, switchgear, motor control centers, panel boards, busway and tie breakers.
3. Working distances shall be based on IEEE 1584. The calculated arc flash protection boundary shall be determined using those working distances.
4. Calculations must be performed to represent the maximum and minimum contributions of fault current magnitude for normal and emergency operating conditions.
5. Multiple system configurations and operating conditions shall be considered and greatest incident energy must be selected for each equipment location.
   1. Provide a tabular view report of all configurations and operating conditions used
   2. Provide calculation methods and assumptions including any adjustments used when considering resistance and impedance tolerances.
6. When applicable, Utility Minimum and Maximum contributions should be considered. Calculations shall also take into consideration the parallel operation of local generators with utility source as well as any stand-by generators.
7. Include scenarios when the main source protective devices are or are not adequately isolated from the bus and may fail to operate or be capable of de-energizing the arc fault before it escalates into a line-side arc fault.
8. Arc flash computation shall include both line and load side of main breaker calculations, where necessary.
9. The Arc flash analysis shall include all MV, 575 volt, & 480 volt locations and significant locations in 240 volt and 208 volt systems fed from transformers equal to or greater than 125 kVA.
10. Arc Flash Study Report:
    1. Arc Flash reports shall compare results from the various arc flash hazard assessments and be capable of filtering the “worst case” Arc Flash analysis results coming from different scenarios in a single table report.
    2. Provide a report in a tabulated format that displays the sequence of operation of protective devices during an arc fault.
    3. Recommendations for arc flash energy reduction including the use of arc reduction maintenance switches, current limiting fuses, replacement of overcurrent protective devices and/or trip units, or replacement of equipment with arc resistant or preventative designs.
11. Software shall utilize data revisions to track system data changes such as “As Found” and “Recommended” settings.
12. Arc Flash Warning Labels:
    1. Consultant shall provide a 3.5 in. x 5 in. thermal transfer type label of high adhesion polyester for each work location analyzed.
    2. All labels will be based on recommended overcurrent device settings and will be provided after the results of the analysis have been presented to the Company and after any system changes, upgrades or modifications have been incorporated in the system.
    3. The label shall include the following information, at a minimum:
       1. Location
       2. Nominal voltage
       3. Flash protection boundary
       4. Hazard risk category
       5. Incident energy
       6. Working distance
       7. Engineering study number, revision number and issue date
    4. Arc Flash warning label sample is shown below:
    5. 
    6. Labels shall be machine printed, with no field markings.
    7. Arc flash labels shall be provided in the following manner and all labels shall be based onrecommended overcurrent device settings.
       1. For each 600, 480 and applicable 208 volt panelboard, one arc flash label shall be provided
       2. For each motor control center, one arc flash label shall be provided
       3. For each low voltage switchboard, one arc flash label shall be provided
       4. For each switchgear, one flash label shall be provided.
       5. For medium voltage switches one arc flash label shall be provided
    8. Labels shall be installed by the engineering services division of the Company under the Startup and Acceptance Testing contract portion.

1. Project Training
   1. Training will be on-site and for duration of three (3) days for two (2) electrical engineers from Client’s staff. The training will include:
      1. Basic use of ETAP package as outlined in the software package tutorials and user’s guide manuals.
      2. Explanation of procedures that were used in developing the topology and the set-up of this project.
      3. Steps that would be involved in modifying and/or expanding system topology for the future revisions and/or upgrades of the equipment and the plant electrical distribution configuration.
      4. The use of the device library and the procedures in creating new devices or modifying existing devices.
2. Arc Flash Training
   1. Consultant shall train the owner’s qualified electrical personnel of the potential arc flash hazards associated with working on energized equipment (minimum of 4 hours).
   2. The training shall be certified for continuing education units (CEUs) by the International Association for Continuing Education Training (IACET) or equivalent.