Appendix_B-_DLA_Tinker_Electrical_Power_System_Assessment.pdf

BLDG 504 & 506

ELECTRICAL

ASSESSMENT

ELECTRICAL EMERGENCY TRANSFER

SYSTEM ASSESSMENT

BACKUP POWER ASSESSMENT

Final Report, 20 Oct, 2015

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ELECTRICAL EMERGENCY TRANSFER SYSTEM AND BACKUP POWER GENERATION

ASSESSMENT, BLDG 504 & 506 DLA DISTRIBUTION OKLAHOMA CITY, OK

Responsible Agency: Defense Logistics Agency (DLA).

Affected Location: DLA Distribution Oklahoma City, OK (DDOO)

Report Designation: Electrical Assessment Building 504 & 506

Abstract: DDOO leadership have lost confidence in reliable power transfer during emergencies. Per leadership, “5 years ago, power transferred smoothly during emergencies; two years ago, problems began to occur regularly; we haven’t seen a smooth transfer since.”

As a result of these past equipment failures, DLA Installations Support for Distribution requested an independent condition assessment and evaluation of the condition and performance of electrical equipment and associated electrical power distribution system in Bldg 506, along with engine generator, transfer equipment, switchgear equipment, and associated electrical power distribution system in Bldg 504 (which supports Bldg 506).

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DLA DISTRIBUTION OKLAHOMA CITY, OK | BLDG 504 & 506 ELECTRICAL ASSESSMENT

TABLE OF CONTENTS

ABBREVIATIONS AND ACRONYMS ................................................... INSIDE FRONT COVER

ABSTRACT

1.0 INTRODUCTION

1.1 Description of Bldg 504 & 506 Function

1.2 Purpose of Report

1.2.1 Building 506 – General Description of Electrical Service

1.2.2 Assessment of Existing Head-end Electrical Service and Stand-by

Power System

1.3 Investigation Methodology

1.3.1 Introduction to DLA Distribution Staff and Safety Procedures

1.3.2 Interior Electrical System

1.3.3 Backup Power

1.3.4 Director’s Out Brief

2.0 SYSTEM OVERVIEW

2.1 Medium Voltage and Normal Side (Utility) Distribution System Description

2.2 Stand-by Generator Side Distribution System Description

3.0 ELECTRICAL SYSTEM ASSESSMENT

3.1 Existing Conditions

3.1.1 Unit Substations (USS) #1 and #2

3.1.2 Automatic Transfer Switches (ATS) #1 and #2

3.1.3 Main (Secondary) Switchboards MS1 and MS2

3.1.4 Generators B1 and B2

3.1.5 Generator Control Switchgear

4.0 COURSES OF ACTION

4.1 Summary of Site Survey Observations

4.2 Operational Impact of Power Outages

4.3 Courses of Action (COA)

4.3.1 Status Quo

4.3.2 COA 1: Basic, Operational Preventive Maintenance

4.3.3 COA 2: Component Replacement

4.3.4 COA 3: Selective Equipment Replacement

5.0 ROUGH ORDER OF MAGNITUDE COST ESTIMATES

6.0 FINAL RECOMMENDATION

7.0 LIST OF PREPARERS

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LIST OF FIGURES

Figure 1: Unit Substation MS-1 Figure 2: Generator B1 Figure 3: Medium Voltage Switch and 1500kVA Dry Type Transformer Figure 4: Automatic Transfer Switch - Internal Components Figure 5: GE Power Break - 2000 A Main Circuit Breaker Figure 6: Simplex Generator Control Switchgear Figure 7: Simplex Generator Control Components Figure 8: Basler Electric Generator Control Components Figure 9: BBC K-Line Circuit Breaker Figure 10: Zinsco Motor Control Center

APPENDICES

APPENDIX A. As-Built Partial One-Line Diagrams APPENDIX B. Rough Order Of Magnitude Cost Backup

1.0 INTRODUCTION

1.1 Description of Bldg 504 & 506 Function

The DLA Distribution Oklahoma City, Oklahoma, provides a full range of distribution services in support of the Oklahoma City Air Logistics Center, Tinker Air Force Base tenants, and other global customers.

Core services include receiving, storage, packaging, and issue of military supplies. Support to the Oklahoma City Air Logistics Center is primarily for programmed depot maintenance for numerous aircraft and engines and is available around the clock. The majority of the items shipped from Oklahoma City are destined for customers on base including the 552nd Air Control Wing, the U. S. Navy Strategic Communications Wing One, the 507th Air Refueling Wing and the 3rd Combat Communications Group.

Off-base shipments from Oklahoma City support customers on Air Force bases worldwide with the various systems and commodities that have been repaired at Tinker Air Force Base. Oklahoma City is one of 25 distribution centers under the command of the Defense Distribution Center, a field activity of the Defense Logistics Agency.

DLA Distribution Oklahoma City has a global, 24/7 mission to support the Department of Defense’s global operations as well as the Federal Emergency Management Agency (FEMA) during emergencies.

The team emphasized the need for reliable and continuous power in all circumstances.

Building 504 is the Engine Generator Building supporting the DLA Distribution Tinker Headquarters Building 506 and Building 416. Building 504 contains two generators and their associated components.

Building 506 functions as one-third administrative space and two-thirds warehouse space. Building 506 includes two electrical mezzanines, one with high voltage switchgear. Building 416 is out of the scope of this study but mentioned for understanding of Building 504 generator power support requirements. We recommend DLA include performance of a condition assessment for Building 416 as a part of the final COA selection.

1.2 Purpose of Report

1.2.1 Building 506 – General Description of Electrical Service The Building 506 backup power standby system has experienced problems with reliable transfer of the facility electrical load from the normal (utility) power to stand-by (generator) power on several occasions in the past 2-5 years. The facility’s mission requires a backup power system that is reliable and ensures continuous power to support the facility’s operation in all circumstances.

DLA Installation Support for Distribution tasked HDR, Inc. to assess the electrical system, concentrating on the building’s dual service switchgear, the standby power system, and the interaction points between the two modes (normal and stand-by) power. The goal is to offer a recommendation of short term and long term issues that need to be addressed.

The normal power to the building is served via the existing 12.47 kV base primary system. The direct service entrance to the building is not served by the local utility company, Oklahoma Gas and Electric, and is from the base primary system.

The interior electrical system, cables and components, are owned by DLA. 507th Civil Engineering Squadron and Tinker Support Services performed operation and maintenance of the system via contract with DLA Installation Support until April 2015. After April 2015, DDOO contracted separately with Advanced Construction Solutions (ACS) to provide facility maintenance support to their buildings.

1.2.2 Assessment of Existing Head-end Electrical Service and Stand-by Power System Power outages to Building 506 are generally attributed to a storm event or other utility outages in either the base primary system or from the utility serving Tinker AFB. Per the inbrief meeting, the building’s users and staff stated that the stand-by power system has effectively worked to their knowledge as recently as five years ago and has since had reliability issues dating back to an outage event approximately 2 years ago. There has been a “loss of confidence” in the building’s backup power system.

HDR was tasked to review the existing backup power system and electrical service entrance to the building, specifically the interactions between the generator systems and the building power system, and to provide an assessment of the system with recommendations for the facility’s need for reliable stand-by generator power.

1.3 Investigation Methodology

1.3.1 Introduction to DLA Distribution Staff and Safety Procedures DLA Distribution Oklahoma City James Carpenter, Facilities Manager hosted HDR representatives Doran McMahon, PE (electrical engineer) and Carmen Goyette (project manager). Work began with a safety and security brief from James Carpenter.

HDR representatives then met with Mr. Ned LaViolette, Director DDOO and members of the ACS Maintenance Team where Mr. LaViolette provided an overview of the DDOO and Building 506 function and operation. A tour of Buildings 504 and 506 followed to help visualize the operation and building layout in the massive facility. HDR representatives discussed with Mr. Carpenter along the way the complexity of the inter-relationship of electrical panels, electrical zones and operational zones (see Section 2.2). The team also discussed and identified critical systems for backup power, specifically the need to keep DLA computer servers running continuously.

1.3.2 Interior Electrical System

HDR was provided the 1973 Logistical Materials Processing Facility drawings, the 1984 As-Built Emergency Backup Power Facilities drawings for Building 506, and the 1991 As-built drawings showing the generator back-up power and service entrance partial one-line diagrams. Field observations noted no significant changes from the original drawings. The Automatic Transfer Switches were replaced/refurbished (original enclosure with relatively new interior components was observed) sometime this year (2015). See Appendix A for one-line diagrams.

1.3.3 Backup Power

While on-site HDR met with the DLA Distribution Oklahoma City staff and the facility staff to receive input on the impact of power outages and concerns with the operation of the stand-by power system.

It was noted during the site visit that there is a lack of service for the maintenance of the buildings’ electrical system and the history or records were not available. As previously mentioned, the facility staff has a “loss of confidence” in the stand-by power system and the system is not regularly exercised or tested for fear of creating unnecessary outages or risking not having the stand-by power system available.

Furthermore, during the site visit, it was also noted that the generators were to be assessed by an independent contractor. HDR has requested the results of the generator assessment and any other existing maintenance or testing documentation of the relevant electrical systems. HDR conducted a conference call to discuss the generator assessment results on September 8, 2015 and is further discussed in Paragraph 3.1.5.

1.3.4 Director’s Out Brief

Upon completion of the field work, HDR provided an out brief to DLA Distribution Oklahoma City Director, Mr. LaViolette. HDR stated there were no safety issues or egregious maintenance issues immediately discernable. HDR provided three initial courses of action (COA) to be fleshed out in this report. Mr. Carpenter asked if the courses of action would be weighted and HDR stated they would be prioritized by cost and complexity. Mr. LaViolette was pleased with the COAs.

***NOTE: During research for this report, COA 2 became the most costly and complex as many of the pieces of equipment HDR preliminarily recommended for simple internal component replacement are no longer supported by their manufacturer. Therefore, the COAs are no longer prioritized by cost and complexity. However, HDR does provide a final recommendation to proceed with COA 2.

2.0 SYSTEM OVERVIEW

DLA Building 506 at Tinker AFB was designed in 1973 as a Logistical Materials Processing Facility. The normal (utility) electrical service to the building is served by two underground 12.47 kV circuits. These circuits appear to be part of the base primary loop and terminate in an outdoor distribution switch station before entering the building.

2.1 Medium Voltage and Normal Side (Utility) Distribution System Description The medium voltage (MV) distribution for Building 506 consists of two MV feeds, each serving a unit substation that generally splits the building load into two parts. One portion of the facility is fed from unit substation (USS) MS- 1 (West) and the other from unit substation MS-2 (East).

The USSs are nearly identical and are each fed by a 12.47kV medium voltage feed and enter the building and terminate on the line side of the load interrupter switches MS#1 and MS#2 respectively. Each medium voltage switch serves a 1500kVA, 12.47kV delta - 480/277V wye, dry-type transformer. The secondary side of each transformer is directly flanked by an automatic transfer switch, ATS#1 and ATS#2. The addition of these ATSs were part of a later modification to the electrical distribution system to install generator back-up. Each ATS is directly connected to the main switchboards, MS1 and MS2 and also has the ability for bypass via a bypass circuit breaker that connects the secondary side of the 1500kVA transformer to the switchboard.

Each switchboard is 2000A rated with a main circuit breaker and has a distribution section populated with circuit breakers serving the remaining electrical distribution system. Refer to Appendix A for the relevant as-built record one-line diagrams.

2.2 Stand-by Generator Side Distribution System Description

The standby generator system originates in building 504 and includes two 670kW (stand-by rating) diesel gensets, Generator “B1” and “B2”. Each genset is connected to a generator control synchronizing switchgear. The generator switchgear is a mirrored line up with an identical generator control section and output circuit breaker for each generator, B1 and B2 respectively. The generator switchgear has a synchronization control section and a tie/paralleling circuit breaker, which is padlocked in the open position. When this tie breaker is padlocked in the open position, the normal operation is for each generator to serve its connected load independently from the other generator and the two are not synchronized together. This appears to be the normal operation of this system, but as originally designed, Figure 1: Unit Substation MS-1 should have the capability of synchronizing both generators and serving the building load simultaneously. This alternate mode requires strategic manual load shedding of building loads as well as a sequence of operations to the bypass control arrangement. Two busduct feeders, B1 and B2 exit the generator switchboard in building 504 then leave to enter building 506. The busduct feeder B1 interfaces with ATS#1 and busduct feeder B2 interfaces with ATS#2 in each of the respective USS line-ups, essentially serving one half of the buildings electrical distribution system per side. The standby generator system also serves building 416. A bus plug unit is connected to busduct B1 (Genset B1) and has a separate feeder serving a separate automatic transfer switch, ATS#3 in building

416. Building 416 was not assessed further and is beyond the scope of work for this assessment. We recommend DLA include performance of a condition assessment for Building 416 as a part of the final COA selection.

3.0 ELECTRICAL SYSTEM ASSESSMENT

3.1 Existing Conditions

3.1.1 Unit Substations (USS) #1 and #2

The existing unit substations, USS #1 and #2, are nearly identical and consist of a medium voltage load interrupter switch, a dry type transformer, automatic transfer switch, and a secondary switchboard distribution section arranged in a single line-up. For the purpose of this section, the USSs will be considered as made up of the medium voltage load interrupter switch and dry type transformer only. The other components of the lineup will be addressed separately.

Both of the USSs were part of the original installation that dates back to 1973. Each medium voltage switch was manufactured by Zinsco Electrical Products (Zinsco), 600A rated, load interrupter switch. Both switches appear to be in fair condition and have been in service for approximately 42 years. There was no apparent damage and the switches were in operation during the time of the survey. However, it should be noted that this equipment is considered obsolete, as this product line has been discontinued and Zinsco is no longer in business.

Like the medium voltage switches, the two dry type transformers were also part of the original installation and have been in service for approximately 42 years. Each transformer was manufactured by Sylvania, 1500 kVA, 12.47 delta – 480Y/277V. The transformers do not show any apparent damage and appear to be in fair condition considering their age. However, it should also be noted that Sylvania is no longer in the business of manufacturing this type of equipment and is considered obsolete. The transformers cool their core and coil windings by convection air movement of hot air out the top vents and entry of ambient air through the bottom vents. The electrical mezzanines are quite dirty with a thick black dusty film and it is likely that the transformer coils are covered with this same film caused by the air movement through the

Figure 3: Medium Voltage Switch and 1500kVA Dry Type Transformer

Figure 2: Generator B1 transformer enclosure. If the transformer can not dissipate the heat because of a filmy build-up the insulation operates at a higher temperature and decays faster.

Information for maintenance records and other data regarding the condition of the USSs was not available at the time of the survey and report.

3.1.2 Automatic Transfer Switches (ATS) #1 and #2

The existing automatic transfer switches (ATS), ATS #1 and #2, are nearly identical and are part of the USS line-up, installed on the load (secondary) side of the 1500kVA dry type transformer and before the secondary distribution switchboard section.

Both of the ATSs were part of a modification to the original electrical distribution installation that introduced generator back up to Building 506. This modification was originally installed in 1984. The ATSs were manufactured by Russelectric.

According to interviews of facility staff during the site visit, approximately 2 years ago the ATSs did not operate properly and did not transfer from normal power to generator power during the loss of utility power. There was no record or any other indication of the cause of non-transfer or any other deficiencies noted with the original ATS installation. There was also no concrete evidence that the ATSs or any other related equipment was the culprit of the non-transfer. Since the incident(s) of non-transfer, the ATSs have had a major overhaul and the interiors have been completely refurbished, approximately 6 months ago (2015). In their current state and at the time of the site survey, both switches appear to be in like new condition and were being operated in the normal (utility) position. Facility staff mentioned that the last scheduled transfer test successfully occurred in April 2015. There have been no scheduled or unscheduled outages with associated power transfer since April 2015.

Although the ATSs are like new, there was no additional information for maintenance records or other data regarding the ATSs available at the time of the survey and report.

3.1.3 Main (Secondary) Switchboards MS1 and MS2

The existing main (secondary) switchboards, MS1 and MS2 have nearly identical ratings and characteristics. Each switchboard is generally configured to serve one half of the building’s electrical load, MS1 serving the “west” side of the building and MS2 serving the “east” side of the building.

Both of the switchboards were part of the original installation that dates back to 1973. Each switchboard is equipped with a 2000A main circuit breaker, with a 2000A rating plug.

Both main circuit breakers are identical General Electric (GE), Power Break insulated case circuit breakers. Both circuit breakers appear to be in fair condition and have been in service for approximately 42 years. There was no apparent damage to the circuit breakers

Figure 4: Automatic Transfer Switch

- Internal Components

Figure 5: GE Power Break - 2000 A Main Circuit Breaker and they were in operation during the time of the survey. The circuit breakers are the first generation version of the GE Power Break line of breakers. GE discontinued the Power Break I circuit breaker in 2008 but offers an engineered retrofit solution replacement for the obsolete circuit breakers.

The distribution sections of the switchboards consist of several molded case circuit breakers of varying sizes that support the existing building loads. The majority of the feeder circuit breakers are original from the 1973 installation and are also approximately 42 years old. The distribution circuit breakers appear to be in fair condition based on their age and there was no mention of nuisance tripping, other concerns, or issues with these circuit breakers. These breakers are also of GE make and many of the frames are obsolete but have retrofill solutions available.

Information for maintenance records and other data regarding the condition of the switchboards and associated circuit breakers was not available at the time of the survey and report.

3.1.4 Generators B1 and B2

The existing generators, B1 and B2, are nearly identical and have the same nameplate ratings, 670 kW (standby rating), 3 phase, 480/277V, .8 pf, 1800 RPM. As with the rest of the building’s electrical distribution, each generator is configured to handle one half of the building’s electrical load.

As described in the ATS section (Paragraph 3.1.2), both of the generators were part of the same modification to the original electrical distribution installation that introduced generator back up to Building

506. This modification was originally installed in 1984 and the generators have been in service for approximately 31 years.

The generators are Stewart & Stevenson diesel engines. The gensets show some signs of leaking fluids and normal wear but are in otherwise fair condition, considering their age. Stewart & Stevenson is still in business and offers service and maintenance for their legacy products.

The existing fueling system consists of a day tank located in Building 504 and underground storage tank located outside and adjacent to Building 504. The fuel system consists of fuel lines to the generator and fuel pumps. During the site visit, the observable fuel system appeared to be part of the original generator system and was in working order. The underground components were not surveyed and the condition is unknown.

As described in Paragraph 3.1.2, approximately 2 years ago, the ATSs did not operate properly and did not transfer from normal power to generator power during the loss of utility power. It is not known if the generators started during this event and other non-transfer events. There is no record, test, or concrete evidence why the transfer did not occur, but since the ATSs have been replaced, it appears that the system does transfer to generator power during loss of normal (utility) power. The last successful transfer test occurred in April 2015.

There was no additional information for maintenance records or other data regarding the generator run, transfer, and parallel operation at the time of the survey and report.

3.1.5 Generator Control Switchgear

The existing generator control switchgear is co-located with the two generators in building 504. The generator control switchgear was also part of the modification to the original electrical distribution installation that introduced generator back up to Building 506. This modification was originally installed in 1984 and has been in service for approximately 31 years.

The switchgear is branded as Simplex Generator Control manufactured by Simplex, Inc., Springfield, Illinois. The Simplex switchgear engine control components appear to be fair condition, considering their age. However, it should be noted that, according to Simplex, Inc. corporate service department, this equipment has been discontinued by Simplex, Inc. since approximately 1993. Because of the discontinuation, the equipment is no longer supported and spare parts are no longer available.

Additional generator control components are housed in a separate section within the generator control switchgear.

These components generally make up the synchronous generator controls and excitation system and are mostly manufactured by Basler Electric. Basler Electric is still in business and offers a range of support for their legacy systems, including retrofit options. The components in this section appear to be in fair condition, considering their age.

The output circuit breakers and tie-breaker are of Brown, Boveri Electric, Inc. (BBC) make. The three circuit breakers are identical, 1600A frame, 1000A trip, K-Line Power Circuit Breakers. The BBC branded circuit breakers are no longer available as BBC merged with ASEA and was renamed ABB over 25 years ago. Legacy products are now part of the ABB lineage of products and service, refurbishment, and reconditioning of BBC K-line circuit breakers is offered by ABB.

Following the site visit, HDR received information from the facility management group during a conference call on September 8, 2015 regarding the results of a recent inspection of the generator control switchgear. Per the discussion, the tie bus has some apparent damage and the tie-breaker has been locked out/tagged out in the open position to prevent operation. The inspection report stated that this breaker has been locked out in this position for an extended amount of time, since approximately 1991 to present. The report also stated, “Advised by CE to not transfer…” with concerns that there is a high probability of equipment failure. It should be noted that the existing inoperable state, due to the lock out of the tie-breaker, limits the functionality of the generator stand-by power system as it was originally designed. The original design allowed for the capability to synchronize the generators on a common bus and to simultaneously support the entire building load with a sequence of breaker operation and load shedding.

Although this does not appear to have been the preferred mode of operation, the original design allowed for this scenario. Now that the tie-breaker is permanently locked out and is not to be operated, this functionality is no longer an option.

Figure 6: Simplex Generator Control Switchgear

Figure 7: Simplex Generator Control Components

Figure 9: BBC K-Line Circuit Breaker

Figure 8: Basler Electric Generator Control Components

As described in Paragraph 3.1.2, approximately 2 years ago, the ATSs did not operate properly and did not transfer from normal power to generator power during the loss of utility power. It is not known if the generators started during this event or other non-transfer events or if the generator control switchgear had a role in the non-transfer. There is no record, test, or concrete evidence why the transfer did not occur, but since the ATSs have been replaced, it appears that the system does transfer to generator power during loss of normal (utility) power. The last successful transfer test occurred in April 2015.

There was no additional information for maintenance records or other data regarding the generator control switchgear.

3.1.5.1 General Observations

The grounding electrode system in Building 504 and in Building 506 was observed during the site visit and appears to be in place and properly connected. The grounding systems do not appear to be deficient and there was not any concern relayed from the building staff. There was no additional information for maintenance records or other data regarding the grounding systems.

During the observation of the secondary side switchboards, MS1 and MS2, portions of the existing distribution system installed in close proximity were observed, specifically the motor control centers. The motor control centers appear to be part of the original electrical installation, dating back to 1973. This equipment is of the Zinsco Electrical Products (Zinsco) make. Similar to the USS medium voltage switches, it should be noted that this equipment is considered obsolete, as this product line has been discontinued and Zinsco is no longer in business.

4.0 COURSES OF ACTION

4.1 Summary of Site Survey Observations

As stated in the site survey outbrief on August 6, 2015, the site survey did not produce a “smoking gun” that would definitely identify the reason for past non-transfer events from normal power to generator power. There were no egregiously bad infrastructure and the building’s electrical system was operating in normal (utility) mode during the site survey. However, there was limited maintenance history and records were not available of testing and operating the circuit breakers, general maintenance like torqueing and tightening connections, cleaning of transformer interiors, etc.

Much of the building’s electrical distribution systems have been in operation for over 40 years and the stand-by generator power system has been in operation for over 30 years. Life expectancy of electrical equipment varies based on many factors, including physical environment, scheduled maintenance, and exposure to undesirable power quality events. Furthermore, electrical equipment life is often directly correlated to the insulation life, i.e. the insulation material that supports and surrounds the equipment.

For the type of equipment that was part of this assessment, published manufacturer’s data suggests that the insulation life expectancy range is generally from a minimum of 20 years and upwards of 30 years. It is not uncommon for electrical equipment to function properly in excess of the expected useful life range but is dependent on the quality of maintenance and the installed environment.

Figure 10: Zinsco Motor Control Center

4.2 Operational Impact of Power Outages

DLA Distribution has a global 24 hours, seven day a week mission to support the Department of Defense’s global operations as well as the Federal Emergency Management Agency (FEMA) during emergencies. The need for continuous power in all circumstances is acute.

4.3 Courses of Action (COA)

4.3.1 Status Quo

The electrical distribution system operates as expected in normal (utility) mode. All indications from building staff is that the stand-by generator system did successfully start as recently as April, 2015.

However, the generator system is not regularly run or jogged and the building load is not transferred to stand-by generator mode since the facility staff does not have confidence in a successful transfer and does not want to unnecessarily cause a building outage. The electrical distribution system, normal (utility) and generator power, can be left as is and resume regularly scheduled maintenance.

The advantage of this alternative is there is no additional capital cost to implement this solution.

The disadvantage of this alternative is that Building 506 can face power outages to critical parts of the operation in the event of an outage and failure of existing electrical equipment. Exposure to future outages remains.

4.3.2 COA 1: Basic, Operational Preventive Maintenance

Perform basic operational preventative maintenance, based on NETA (InterNational Electrical Testing Association) Standard for Maintenance Testing Specifications for Electrical Power Equipment and Systems (ANSI/NETA MTS-latest version). This preventative maintenance would be in accordance with Section 7, sub-section 1. Visual and Mechanical Inspection for the following equipment:

• 7.1 Switchgear and Switchboard Assemblies Main (Secondary) Switchboards MS1 and MS2 Generator Control Switchgear

• 7.2.1.2 Transformers, Dry-Type, Air-Cooled, Large USS#1 and #2 1500 kVA dry-type transformers

• 7.3.2 Cables, Low-Voltage, 600 Volt Maximum All low voltage (600V or less) cable connections in USS #1 and #2 dry-type transformers

(secondary side), Main (Secondary) Switchboards MS1 and MS2, ATS #1 and #2, Generators B1 and B2, Generator Control Switchgear

• 7.3.3 Cables, Medium- and High-Voltage All medium voltage cable connections in USS #1 and #2, including the medium voltage switches and dry-type transformers (primary side).

• 7.4 Metal-Enclosed Busways Busway from Generator Control Switchgear to ATS #1 and ATS #2.

• 7.5.1.2 Switches, Air, Medium-Voltage, Metal-Enclosed USS #1 and #2 Medium Voltage switches MS-1 and MS-2

• 7.6.1.1 Circuit Breakers, Air, Insulated-Case/Molded-Case Main (Secondary) Switchboards MS1 and MS2 Generator Control Switchgear

• 7.6.1.2 Circuit Breakers, Air, Low-Voltage Power Main (Secondary) Switchboards MS1 and MS2

• 7.22.1 Emergency Systems, Engine Generator Generators B1 and B2

• 7.22.3 Emergency Systems, Automatic Transfer Switches ATS #1 and ATS #2

The advantages of this COA:

• Power outages required for the visual and mechanical inspections and maintenance can be scheduled to minimize the impact to the Building 506 mission. Power outages will likely be less extensive as compared to outages required for COA #2 or #3.

• Lower capital investment, since existing electrical equipment will remain.

The disadvantages of this COA include:

• Exposure to future outages remains. Even with inspection and maintenance, the existing equipment will remain and the issue of higher probability of failure due to age and availability of replacement parts and/or service options remains.

• Inspection and maintenance, both preventive and to repair failures that occur, may lead to replacing equipment since many components of the electrical distribution are obsolete.

• Power outages will be required.

4.3.3 COA 2: Component Replacement

Replace the Building 506’s “head end” electrical distribution system in kind with new equipment. This would include USS #1 and #2 (medium voltage switches MS-1 and MS-2 and 1500 kVA dry-type transformers), ATS #1 and #2, Main (Secondary) Switchboards MS1 and MS2, Generators B1 and B2, Generator Control Switchboard, Generator fuel system (including day tanks, underground storage tank and associated fuel lines, pumps, battery chargers and spill containment), medium voltage cable to USS #1 and #2, and busduct from the Generator Control Switchboard to ATS #1 and #2.

The component replacement option would include upgrading and re-designing the associated electrical equipment to best support the current facility needs and would not be limited to "in-kind" replacement.

The new design should consider optimizing the size of all components based on peak demand load of the building. The new generator system is recommended to have the capability of paralleling multiple generators to support the entire building with automatic features for transfer and load shedding. Closed transition automatic transfer switches should be considered to allow for regular scheduled testing and jogging of the generators while being connected to building load and to not interrupt power. New digital metering ("smart metering") should be included in new equipment capable of power and energy measurements, power quality analysis, and data/event logging. Existing protective relaying shall be replaced with new and the design should address needs for the medium voltage equipment as well as the switchboards and generator equipment. In order to accurately design for the new equipment, a short circuit/coordination/arc flash study and a power factor correction study for these two buildings are also recommended as part of the new equipment installation. Also, electrical clearance issue assessments, alternative location assessments for the new equipment and their supporting systems, and remote generator status panels/computer interface requirement assessments are recommended during the design phase.

The advantages of this COA include:

• New equipment will be the current make and model of electrical equipment manufacturer lines.

New equipment will have lower probability of failure as compared to the aged equipment.

• Readily available replacement parts and service availability will reduce down time in case of undesirable power events.

• Restoration of reliable transfer of power from normal (utility) power to generator power to support mission requirements for continuous power.

The disadvantages of this COA include:

• Will require power outage to demolish and replace existing equipment with new. This option will likely have the most extensive down time of the COA’s. Phasing and temporary power considerations, which must be appropriately determined and budgeted for during design, may reduce down time but will require considerable coordination during design and construction.

Permitting for new generators and their fueling support systems will require various permits through base and environmental agencies which must be addressed in design.

• Highest capital investment of the COA’s.

4.3.4 COA 3: Selective Equipment Replacement

Selectively replace a portion of Building 506’s electrical distribution system, limited to the Generator Control Switchboard and USS#1 and #2 (medium voltage switches MS-1 and MS-2 and 1500 kVA dry-type transformers) in kind with new equipment. The remaining “head end” electrical equipment and electrical distribution system would remain in place, including ATS #1 and #2, Main (Secondary) Switchboards MS1 and MS2, Generators B1 and B2.

The advantages of this COA include:

• Equipment scheduled for replacement will be the current make and model of electrical equipment manufacturer lines. New equipment will have lower probability of failure as compared to the aged equipment.

• For equipment scheduled for replacement, readily available replacement parts and service availability will reduce down time in case of undesirable power events.

The disadvantages of this COA include:

• Will require power outage to demolish and replace existing equipment with new. Phasing and temporary power considerations, which must be appropriately determined and budgeted for during design, may reduce down time but will require considerable coordination during design and construction.

• High capital investment, however less than COA 2.

• Exposure to future outages remains. This COA does not replace all electrical equipment that has been in service in excess of 30 years. A higher probability for a failure in obsolete or old equipment remains.

6.0 FINAL RECOMMENDATION

COA #2 is recommended to best support the mission of Building 506. The driver for this recommendation is related to the age of the equipment. As previously mentioned, the type of electrical equipment assessed will generally have a useful life expectancy around 30 years. Much of the assessed equipment is considered obsolete, as many manufacturers of the original equipment are either no longer in business or have been absorbed by a different company. The obsolete equipment has limited replacement parts, limited service options, and in some cases, are no longer available. This equipment would be considered the “weakest link” and a failure to this equipment would result in limited options for replacement and/or repair, causing excessive down time.

APPENDIX A. AS-BUILT PARTIAL ONE-LINE DIAGRAMS

A-1

A-2

A-3

A-4

6.0 FINAL RECOMMENDATION