Addendum No. 1

Georgia Southwestern State University GSW 20-04-21 Library Electrical Service Upgrade

NBP #21071

ADDENDUM NO. 1

A1 - 1

This Addendum forms part of the Contract Documents and modifies the original bidding documents dated August 31, 2021. Acknowledge receipt of this Addendum in the space provided on the Bid Form. Failure to do may subject the bidder to disqualification.

The contract documents are herein amended under the date of October 4, 2021 as follows:

RESPONSES TO QUESTIONS FROM BIDDERS

1) Sheet E0.0 – Panel LX has no notes. Does it stay or get replaced?

1a) Refer to NOTES section in bottom left corner of Panel LX schedule on Sheet E3.0.

2) Sheet E0.0 – Disconnect for CHR-2 same question 2a) This disconnect and all disconnects associated with HVAC equipment are existing to remain.

3) Sheet E3.0 – The notes in Panel HA mentions a NEW 5 KVA transformer. This is not on the one-line or plan view.

3a) Include the cost for this 5 KVA, 480V:240V single phase transformer in the project. The existing transformer shall be replaced in place with a new transformer of the same size.

4) Is a short-circuit/arc fault/coordination study required as part of the scope of work?

4a) Yes, refer to attached new Specification Section 26 0573 – Protective Device

Coordination Study.

5) Should new dry type transformers be tied back to building steel?

5a) Yes.

6) If there are existing disconnects associated with the dry type transformers being replaced, should those disconnects also be replaced?

6a) Yes.

7) Which switchboards/panelboards will require Surge Protective Devices?

7a) The new Main Switchboard DP, Panel LX, Panel LA, Load Center described by Note 9 on Sheet E0.0, and Panel LC. Provide 30A/3P circuit breakers (or as recommended by SPD manufacturer) in each of these switchboards/panelboards for the Surge Protective Device.

AMENDMENTS TO THE SPECIFICATIONS

1. Add attached SECTION 26 0573 – PROTECTIVE DEVICE COORDINATION STUDY.

END OF ADDENDUM

Georgia Southwestern State University October 4, 2021 GSW 20-04-21 Library Electrical Service Upgrade 100% Construction Documents

NBP#21071

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 1

SECTION 26 0573

PROTECTIVE DEVICE COORDINATION STUDY

PART 1 GENERAL

1.01 SECTION INCLUDES

A. Short-circuit study.

B. Protective device coordination study.

C. Arc flash and shock risk assessment.

1. Includes arc flash hazard warning labels.

1.02 REFERENCE STANDARDS

A. NFPA 70 - National Electrical Code, 2020 Edition.

1.03 ADMINISTRATIVE REQUIREMENTS

A. Coordination:

1. Coordinate the work to provide equipment and associated protective devices complying with criteria for selection and adjustment, as determined by studies to be performed.

2. Notify Architect of any conflicts with or deviations from the contract documents. Obtain direction before proceeding with work.

B. Sequencing:

1. Submit study reports prior to or concurrent with product submittals.

2. Do not order equipment until matching study reports and product submittals have both been evaluated by Architect.

1.04 SUBMITTALS

A. See Section 26 0510 - General Electrical Requirements for submittal procedures.

B. Study preparer's qualifications.

C. Study reports, stamped or sealed and signed by study preparer.

D. Study Report: Submit short circuit and protective device studies as specified, prior to submission of product data submittals or ordering or fabrication of protective devices.

1. Evaluation of product data submittals by Architect will not commence until acceptable studies have been submitted.

2. Include stamp or seal and signature of preparing engineer.

E. Field Engineer Qualifications.

F. Field Inspection Report: Show final adjusted settings of protective devices.

G. Certificates: Prior to Material Completion, certify that field adjustable protective devices have been set in accordance with requirements of protective device analysis.

H. Project Record Documents: Revise protective device study as required to show as-built conditions.

1. Submit not less than 60 days prior to final inspection of electrical system.

2. Include hard copies with operation and maintenance data submittals.

3. Include computer software files used to prepare studies with file name(s) cross-referenced to specific pieces of equipment and systems.

1.05 POWER SYSTEM STUDIES

A. Scope of Studies:

1. Except where study descriptions below indicate exclusions, analyze system at each bus from primary protective devices of utility source down to each piece of equipment involved, including parts of system affecting calculations being performed (e.g. fault current contribution from motors).

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 2

2. Include in analysis alternate sources and operating modes (including known future configurations) to determine worst case conditions.

B. General Study Requirements:

1. Comply with NFPA 70, National Electrical Code; 2020 Edition.

2. Perform studies utilizing computer software complying with specified requirements;

manual calculations are not permitted.

C. Data Collection:

1. Compile information on project-specific characteristics of actual installed equipment, protective devices, feeders, etc. as necessary to develop single-line diagram of electrical distribution system and associated input data for use in system modeling.

a. Utility Source Data: Include primary voltage, maximum and minimum three-phase and line-to-ground fault currents, impedance, X/R ratio, and primary protective device information.

1) Obtain up-to-date information from Utility Company.

b. Generators: Include manufacturer/model, kW and voltage ratings, and impedance.

c. Motors: Include manufacturer/model, type (e.g. induction, synchronous), horsepower rating, voltage rating, full load amps, and locked rotor current or NEMA MG 1 code letter designation.

d. Transformers: Include primary and secondary voltage ratings, kVA rating, winding configuration, percent impedance, and X/R ratio.

e. Protective Devices:

1) Circuit Breakers: Include manufacturer/model, type (e.g. thermal magnetic, electronic trip), frame size, trip rating, voltage rating, interrupting rating, available field-adjustable trip response settings, and features (e.g. zone selective interlocking).

2) Fuses: Include manufacturer/model, type/class (e.g. Class J), size/rating, and speed (e.g. time delay, fast acting).

f. Protective Relays: Include manufacturer/model, type, settings, current/potential transformer ratio, and associated protective device.

g. Conductors: Include feeder size, material (e.g. copper, aluminum), insulation type, voltage rating, number per phase, raceway type, and actual length.

D. Short-Circuit Study:

1. Comply with IEEE 551 and applicable portions of IEEE 141, IEEE 242, and IEEE 399.

2. For purposes of determining equipment short circuit current ratings, consider conditions that may result in maximum available fault current, including but not limited to:

a. Maximum utility fault currents.

b. Maximum motor contribution.

c. Known operating modes (e.g. utility as source, generator as source, utility/generator in parallel, bus tie breaker open/close positions).

3. For each bus location, calculate the maximum available three-phase bolted symmetrical and asymmetrical fault currents. For grounded systems, also calculate the maximum available line-to-ground bolted fault currents.

E. Protective Device Coordination Study:

1. Comply with applicable portions of IEEE 242 and IEEE 399.

2. Analyze alternate scenarios considering known operating modes (e.g. utility as source, generator as source, utility/generator in parallel, bus tie breaker open/close positions).

3. Analyze protective devices and associated settings for suitable margins between time-current curves to achieve full selective coordination while providing adequate protection for equipment and conductors.

F. Arc Flash and Shock Risk Assessment:

1. Comply with NFPA 70E.

http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=NFPA%2070 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=NEMA%20MG%201 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%20551 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%20141 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%20242 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%20399 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%20242 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%20399 https://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=NFPA%2070E

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 3

2. Perform incident energy and arc flash boundary calculations in accordance with IEEE 1584 (as referenced in NFPA 70E Annex D), where applicable.

3. Analyze alternate scenarios considering conditions that may result in maximum incident energy, including but not limited to:

a. Maximum and minimum utility fault currents.

b. Maximum and minimum motor contribution.

c. Known operating modes (e.g. utility as source, generator as source, utility/generator in parallel, bus tie breaker open/close positions).

G. Study Reports:

1. General Requirements:

a. Identify date of study and study preparer.

b. Identify study methodology and software product(s) used.

c. Identify scope of studies, assumptions made, implications of possible alternate scenarios, and any exclusions from studies.

d. Identify base used for per unit values.

e. Include single-line diagram and associated input data used for studies; identify buses on single-line diagram as referenced in reports, and indicate bus voltage.

f. Include conclusions and recommendations.

2. Short-Circuit Study:

a. For each scenario, identify at each bus location:

1) Calculated maximum available symmetrical and asymmetrical fault currents (both three-phase and line-to-ground where applicable).

2) Fault point X/R ratio.

3) Associated equipment short circuit current ratings.

b. Identify locations where the available fault current exceeds the equipment short circuit current rating, along with recommendations.

3. Protective Device Coordination Study:

a. For each scenario, include time-current coordination curves plotted on log-log scale graphs.

b. For each graph include (where applicable):

1) Partial single-line diagram identifying the portion of the system illustrated.

2) Protective Devices: Time-current curves with applicable tolerance bands for each protective device in series back to the source, plotted up to the maximum available fault current at the associated bus.

3) Conductors: Damage curves.

4) Transformers: Inrush points and damage curves.

5) Generators: Full load current, overload curves, decrement curves, and short circuit withstand points.

6) Motors: Full load current, starting curves, and damage curves.

7) Capacitors: Full load current and damage curves.

c. For each protective device, identify fixed and adjustable characteristics with available ranges and recommended settings.

1) Circuit Breakers: Include long time pickup and delay, short time pickup and delay, and instantaneous pickup.

2) Include ground fault pickup and delay.

3) Include fuse ratings.

4) Protective Relays: Include current/potential transformer ratios, tap, time dial, and instantaneous pickup.

d. Identify cases where either full selective coordination or adequate protection is not achieved, along with recommendations.

4. Arc Flash and Shock Risk Assessment:

a. For each scenario, identify at each bus location:

1) Calculated incident energy and associated working distance.

http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%201584 http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=IEEE%201584

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 4

2) Calculated arc flash boundary.

3) Bolted fault current.

4) Arcing fault current.

5) Clearing time.

6) Arc gap distance.

b. For purposes of producing arc flash hazard warning labels, summarize the maximum incident energy and associated data reflecting the worst case condition of all scenarios at each bus location.

c. Identify locations where the calculated maximum incident energy exceeds 40 calories per sq cm.

1.06 PROTECTIVE DEVICE STUDY

A. Analyze the specific electrical and utilization equipment (according to NEC definition), the actual protective devices to be used, and the actual feeder lengths to be installed.

1. Scope of Studies: All new distribution wiring and equipment, from primary source to buses and branch circuit panelboards.

2. Study Methodology: Comply with requirements and recommendations of NFPA 70, IEEE 399, and IEEE 242.

3. Report: State the methodology and rationale employed in making each type of calculation; identify computer software package(s) used.

B. One-Line Diagrams: Prepare schematic drawing of electrical distribution system, with all electrical equipment and wiring to be protected by the protective devices; identify nodes on the diagrams for reference on report that includes:

1. Calculated fault impedance, X/R ratios, utility contribution, and short circuit values (asymmetric and symmetric) at the main switchboard bus and all downstream devices containing protective devices.

2. Breaker and fuse ratings.

3. Transformer kVA and voltage ratings, percent impedance, X/R ratios, and wiring connections.

4. Identification of each bus, with voltage.

5. Conduit materials, feeder sizes, actual lengths, and X/R ratios.

C. Short Circuit Study: Calculate the fault impedance to determine available 3-phase short circuit and ground fault currents at each bus and piece of equipment during normal conditions, alternate operations, emergency power conditions, and other operations that could result in maximum fault conditions.

1. Show fault currents available at key points in the system down to a fault current of 7,000 A at 480 V and 208 V.

2. Include motor contributions in determining the momentary and interrupting ratings of the protective devices.

3. Primary Fault Level Assumptions: Obtain data from utility company.

4. Report: Include all pertinent data used in calculations and for each device include:

a. Device identification.

b. Protective device.

c. Device rating.

d. Calculated short circuit current, asymmetrical and symmetrical, and ground fault current.

D. Coordination Study: Perform an organized time-current analysis of each protective device in series from the individual device back to the primary source, under normal conditions, alternate operations, and emergency power conditions. Analysis shall include ground fault devices.

1. Graphically illustrate that adequate time separation exists between series devices, including upstream primary device.

2. Plot the specific time-current characteristics of each protective device on log-log paper.

3. Organize plots so that all upstream devices are clearly depicted on one sheet.

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 5

4. Also show the following on curve plot sheets:

a. Device identification.

b. Voltage and current transformer ratios for curves.

c. 3-phase and 1-phase ANSI damage curves for each transformer.

d. No-damage, melting, and clearing curves for fuses.

e. Cable damage curves.

f. Transformer inrush points.

g. Maximum short circuit cutoff point.

h. Simple one-line diagram for the portion of the system that each curve plot illustrates.

i. Software report for each curve plot, labeled for identification.

5. Emergency Systems: The coordination study shall include coordination of all emergency system overcurrent devices with all supply side overcurrent protective devices. Make necessary adjustments or recommendations for alternate equipment to comply with 2020 National Electrical Code.

6. Elevators: In buildings with more than one elevator supplied by a single feeder, the overcurrent protective devices in each disconnecting means shall be selectively coordinated with any other supply side overcurrent protective devices, including any disconnect or circuit breaker located at an emergency generator. Make necessary adjustments or recommendations for alternate equipment to comply with the 2017 National Electrical Code.

E. Analysis: Determine ratings and settings of protective devices to minimize damage caused by a fault and so that the protective device closest to the fault will open first.

1. Required Ratings and Settings: Derive required ratings and settings of protective devices in consideration of upstream protective device settings and optimize system to ensure selective coordination.

2. Identify any equipment that is underrated as specified.

3. Identify existing protective devices that will not achieve required coordination and cannot be field adjusted to do so.

4. Identify specified protective devices that will not achieve required protection or coordination but with minor changes can be made to do so; provide such modified devices at no additional cost to Owner and identify them on submittals as "revised in accordance with Protective Device Coordination Study"; minor changes include different trip sizes in the same frame, time curve characteristics of induction relays, CT ranges, etc.

5. Identify specified protective devices that will not achieve required protection or coordination and cannot be field adjusted to do so, and for which adequate devices would involve a change to the contract sum.

6. In all cases where adequate protection or coordination cannot be achieved at no extra cost to Owner, provide a discussion of alternatives and logical compromises for best achievable coordination.

7. Do not order, furnish, or install protective devices that do not meet performance requirements unless specifically approved by Architect.

F. Protective Device Rating and Setting Chart: Summarize in tabular format the required characteristics for each protective device based on the analysis; include:

1. Device identification.

2. Relay CT ratios, tap, time dial, and instantaneous pickup.

3. Circuit breaker sensor rating, long-time, short-time, and instantaneous settings, and time bands.

4. Fuse rating and type.

5. Ground fault pickup and time delay.

6. Input level and expected response time at two test points that are compatible with commonly available test equipment and the ratings of the protective device.

7. Highlight all devices that as furnished by Contractor will not achieve required protection.

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 6

G. Arc Flash Hazard Study: Provide an Arc Flash Hazard Study for the electrical distribution system shown on the power riser diagram. The intent of the Arc Flash Hazard Study is to determine hazards that exist at each major piece of electrical equipment shown on the power riser diagram. This includes switchboards, panelboards, automatic transfer switches, and transformers.

1. The study shall be performed after the short circuit and protective device coordination study has been completed based upon IEEE Std. 1584, "IEEE Guide for Performing Arc Flash Hazard Calculations".

2. Pertinent data, rationale employed, and assumptions in developing the calculations shall be incorporated in the introductory remarks of the study.

3. The study shall be in accordance with the latest adopted versions of NFPA 70E, OSHA 29-CFR, Part 1910 Subpart S and IEEE 1584 Standards.

4. The study shall determine the following:

a. Flash Hazard Protection Boundary

b. Limited Approach Boundary

c. Restricted Boundary

d. Prohibited Boundary

e. Incident Energy Level

f. Required Personal Protective Equipment (PPE) Class

g. Type of Fire Rated Clothing

5. The study shall include creation of Arc Flash Hazard Warning Labels. These labels serve as a guide to assist technicians and others in the selection of proper PPE when working around exposed and energized conductors. Include the bus name, system operating voltage, and date of issue. Labels shall be printed in color on adhesive backed labels.

6. The Contractor shall install the warning labels.

1.07 QUALITY ASSURANCE

A. Study Preparer Qualifications: Professional electrical engineer licensed in the State in which the Project is located and with minimum five years’ experience in the preparation of studies of similar type and complexity using specified computer software.

B. Study Preparer Qualifications: Electrical testing agency regularly engaged in short circuit and coordination studies, with at least 5 years’ experience in work of this type, and employing professional electrical engineer licensed in to perform the studies.

C. Computer Software for Study Preparation: Use the latest edition of commercially available software utilizing specified methodologies.

D. The Contractor's Responsibility: Provide all project-related data needed by study preparer, including equipment, wire sizes, insulation types, conduit types, and actual circuit lengths.

PART 2 PRODUCTS

2.01 ARC FLASH HAZARD WARNING LABELS

A. Provide warning labels complying with ANSI Z535.4 to identify arc flash hazards for each work location analyzed by the arc flash and shock risk assessment.

1. Materials: Comply with Section 26 0553.

2. Legend: Provide custom legend in accordance with NFPA 70E based on equipment-specific data as determined by arc flash and shock risk assessment.

a. Include orange header that reads "WARNING" where calculated incident energy is less than 40 calories per square cm.

b. Include red header that reads "DANGER" where calculated incident energy is 40 calories per square cm or greater.

c. Include the text "Arc Flash and Shock Hazard; Appropriate PPE Required" or approved equivalent.

d. Include the following information:

1) Arc flash boundary.

http://global.ihs.com/doc_detail.cfm?rid=BSD&document_name=ANSI%20Z535.4

PROTECTIVE DEVICE COORDINATION STUDY 26 0573 - 7

2) Available incident energy and corresponding working distance.

3) Site-specific PPE (personnel protective equipment) requirements.

4) Nominal system voltage.

2.02 PROTECTIVE DEVICES

A. Provide protective devices of ratings and settings as required so that the protective device closest to the fault will open first.

B. In addition to requirements specified elsewhere, provide overcurrent protective devices having ratings and settings in accordance with results of this analysis.

PART 3 EXECUTION

3.01 INSTALLATION

A. The contractor shall provide a permanent label on the Service Entrance Equipment indicating the available fault current rating at that location per the requirements of the National Electrical Code.

B. Install all labels from the Arc Flash Hazard Analysis at each piece of electrical equipment.

3.02 FIELD QUALITY CONTROL

A. Adjust equipment and protective devices for compliance with studies and recommended settings.

B. Notify Architect of any conflicts with or deviations from studies. Obtain direction before proceeding.

C. Provide the services of a qualified field engineer and necessary tools and equipment to test, calibrate, and adjust the installed protective devices to conform to requirements determined by the coordination analysis.

D. Adjust installed protective devices having adjustable settings to conform to requirements determined by the coordination analysis.

E. Submit report showing final adjusted settings of all protective devices.

END OF SECTION