ML15058A714

Response to NRC Request for Additional Information

ML15058A714
Person / Time
Site:	National Bureau of Standards Reactor
Issue date:	02/26/2015
From:	Dimeo R US Dept of Commerce, National Institute of Standards & Technology (NIST)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML15058A714 (24)

Text

UNITED STATES DEPARTMENT OF COMMERCE National Institute of Standards and Technology 1 A Gaithersburg, Maryland 20899-February 26, 2015 Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

NRC Request for Additional Information Docket No. 50-184 Gentleman:

In response to your letter of January 30, 2015, please find enclosed the NIST Center for Neutron Research (NCNR) answers to the RAI for the license amendment request to change two technical specifications for the station battery. Any questions regarding the NCNR response should be directed to Dr. Paul Brand, Acting Chief, Reactor Operations and Engineering. Dr. Brand may be reached at paul.brand@nist.gov or (301) 975-6257.

Sincerely, Robert M. Dimeo, Director NIST Center for Neutron Research I certify under penalty of perjury that the following is true and correct.

Executed onFEB 2 G)2015 By: Uzi &-

cc: Xiaosong Yin, Project Manager N I"S

Response to RAI of January 30, 2015 NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY TEST REACTOR

1. On page 1 of the LAR, you proposed to replace both NBSR's UPS that supply emergency alternating current (AC) electrical power to reactor critical loads.

NUREG-1 537, Part 1, Section 8.2, "Emergency Electrical Power Systems," states that the information contained in this section should be "commensurate with required design basis developed in other chapters of the SAR."

a) Provide an overview of the systems that are affected by this LAR.

b) Provide a one-line diagram that shows the current and the proposed configurations of the UPS system including the station battery, direct current (DC) Distribution Panel, and Critical Power Panel.

Answer to Questions 1a and 1b: Please see the attached drawings, Before Configuration and After Configuration. Electrical loads, motor control centers, switchboards, etc. were not affected by this change.

The two existing 20 kVA UPS, T9 and T10, were replaced with two 20 kVA UPS of a different design but of the same output capacity. The replacement UPS are designated as MAIN UPS and STANDBY UPS.

Battery power was changed from the existing 60-cell lead-antimony battery bank to the existing 60-cell lead-antimony battery bank + a 72 cell VRLA bank + a spare 72 cell VRLA battery bank. Previously, the Station Battery = 60-cell battery bank; now the Station Battery

= 60-cell battery bank + one VRLA battery bank. No credit for battery power is taken for the spare VRLA battery bank.

The 60-cell battery charging capability of T9 UPS was replaced with a stand-alone battery charger and the 60-cell battery charging capability of the T10 UPS was also replaced with a stand-alone battery charger. In addition, the charging configuration for the 60-cell battery bank has been changed. T9 UPS'and T10 UPS were not in service at the same time; T9 or T10 charged the 60-cell battery. The replacement chargers operate in parallel, both charging the battery, with one charger nominally the primary charger.

2. On page 1 of the LAR, it states:

"Two redundant battery chargers will be purchased and installed to replace the function previously provided by the T-9 and T-10 UPS. The two replacement UPS are state-of-the-art systems with valve-regulated lead acid (VLRA) or sealed batteries rather than flooded or wet lead acid batteries. Each of the redundant UPS and batteries are capable of carrying the 20 kVA (design basis value for NBSR) of AC reactor critical power loads for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> (assumes full 20 kVA loading) independently."

NUREG-1537, Part 1, Section 8.2, "Emergency Electrical Power Systems," states that the information contained in this section should "present a detailed functional description and circuit diagram."

I a) Clarify if the battery charger and the VLRA battery are included in the UPS unit.

Also, provide a simplified block diagram that shows how the UPS, the VLRA battery, and the battery charger are interconnected.

Answer to Question 2.a: The stand-alone battery chargers are not included in the UPS unit and those battery chargers have no interaction with the UPS. A VLRA battery bank is part of an UPS and is charged only through the UPS of which the bank is part. See the excerpts, including simplified block diagrams, from the UPS manual in Attachment 2.

b) Provide manufacturer ratings and specifications of the battery chargers, UPS, and the VLRA batteries.

Answer to Question 2.b: See Attachment 3.

c) Provide a summary of the calculation performed to determine the adequacy of the new equipment (i.e. battery chargers, UPS, VRLA batteries) to supply the reactor critical loads.

Answer Question 2.c: No detailed calculation was performed for the replacement battery chargers. Each stand-alone battery charger was specified for the same input and output capability as the T9 and T10 UPS, which previously maintained the charge on the 60-cell battery bank through the output of the rectifier of the selected UPS. The adequacy of the battery charger design was confirmed after the installation of the battery chargers.

After the chargers were connected to the 125 VDC distribution panel, the battery chargers had a positive DC current indicated with an output voltage of approximately 128 VDC, and the 60-cell battery terminal voltage increased to 128 VDC. The estimated current draw from the required DC loads, the motors for EF-5 and EF-6, is approximately 4 amps at 115 VDC, well within the capacity (108 amps continuous for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />) of the 60-cell battery bank.

No calculation was performed for the replacement UPS. The replacement 20 kVA UPS are of a different design than the replaced UPS, but of the same output capacity. The vendor confirmed the operability of the non-battery section of the UPS during commissioning of the UPS and there was, and has been, no effect upon operability of the AC loads on the output of the UPS after the UPS were placed into service.

The lifetime of the VRLA battery bank was provided by the manufacturer as 124 Ah for 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />, or 24.8 Ah for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, assuming a linear discharge rate. The manufacturer's value for the necessary AC output from the battery bank was checked using a simple equation for the continuous AC power requirement for the UPS: Assuming a power factor of 1, then 20 kVA = 31/2 XI x E, or; 20000 = 31/2 x I x 480, or; I = 24 amps continuously. This is consistent with the manufacturer's value for the battery bank for a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> minimum battery bank lifetime. The estimated current draw from the nuclear instrumentation, the only required AC load, is 3 amps at 115 VAC, well within the capacity of the VRLA battery bank.

The capability of the MAIN UPS VRLA battery bank was confirmed with a discharge test completed on September 5, 2014. The test procedure placed CP-1, CP-2, CP-3, and the Rod Drive Power and Controller as loads (see page 2 of Attachment 1) on the output of the MAIN UPS. With an AC input to the UPS, a battery voltage and current of 498 V and 0 amps was recorded from the UPS control panel, along with a battery lifetime of 481 minutes calculated by the UPS software. The battery bank was in this starting condition of peak voltage and zero amp discharge current, because the AC input was providing all of the AC output and providing a trickle charge to the VRLA battery bank. The AC input was then removed from the UPS, placing the described load on the VRLA battery bank of the MAIN UPS. An initial DC voltage and current of 455 V and 15 amps was recorded, along with a calculated battery life of 419 minutes. After 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, the voltage was 446 V, the current was at 14.7 amps, and the battery lifetime was calculated at 257 minutes. The VRLA battery bank would provide an estimated 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of power to all of the AC loads described as critical; clearly, the battery bank can power the nuclear instrumentation, the only required AC load, for at least 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. A test of the STANDBY UPS VRLA battery bank was performed on November 11, 2014. Similar results were obtained.

3. The current Technical specification (TS) 4.6, "Emergency Power System" requires testing the voltage and specific gravity of each cell of the station battery annually. The proposed revised TS 4.6 does not include these requirements for the VRLA battery. You clarified that the specific gravity of the VRLA battery cannot be measured because the electrolyte of the VRLA battery is immobilized in an absorbed glass matte (AGM).

However, you provided no justification for omitting testing of the VRLA battery cell voltage.

NUREG-1537, Par 1, Section 8.2, "Emergency Electrical Power Systems," states that the information contained in this section should "also identify the. . ., important design parameters, and surveillance and inspection functions that ensure operability of the emergency electric power systems..."

Provide the TS requirement for testing the VRLA battery cell voltage. If this testing is not required for the VLRA battery, provide justification for deviating from the requirement of the current TS 4.6.

Answer to Question 3: Battery cell voltage may be used as an indicator of individual cell degradation. It is not necessarily an indicator of battery bank capacity falling below minimum output. Individual cell battery failures in existing VRLA battery banks at the NCNR have been insignificant in number. A two year discharge test is sufficient to reveal failing or failed battery cells, after which any failed cell would be identified. For details, see answer to question 5.

4. On page 1 of the LAR, the licensee states: "The NCNR [NIST Center for Neutron Research] is not replacing the existing flooded lead acid battery (Vented Lead Acid or VLA), designated as the Station Battery in the Safety Analysis Report, because it is required to supply the various emergency loads that operate on 125 VDC."

a) Provide a copy of the sections of the above Safety Analysis Report (SAR) that are related to NIST emergency electrical power systems including the UPS, the battery chargers, and the station batteries. Also, provide a markup of the changes made to the affected sections as a result of this amendment request.

Answer to 4.a: See Attachment 4.

b) Clarify whether the VRLA batteries supply the various emergency loads served by the Station Battery at any time.

Answer to 4.b: The VRLA batteries do not supply all of the required loads. See the answer to question 1 for the definition of the station battery. The VRLA batteries for the MAIN UPS provide power only to the AC loads and only when the normal (MCC B6) AC input is lost to the MAIN UPS. After the MAIN UPS batteries are fully discharged, the STANDBY UPS will provide AC power to the output of the MAIN UPS. For the sequence of AC power to the AC critical loads, see section 8.1.2.4 in the SAR excerpt in the answer to question 4.a.

5. On page 1 of the LAR, you stated that the VLRA maintenance guidance found in the Institute of Electrical and Electronics Engineers (IEEE) standard 1188-2005, "IEEE Recommended Practice for Maintenance, Testing, and Replacement of Valve-Regulated Lead-Acid (VRLA) Batteries for Stationary Applications," will be used for the VLRA batteries. As described in the IEEE standard 1188-2005, a service test is a test of the battery's ability, as found, to satisfy the design requirements (battery duty cycle) of the DC system.

Provide an explanation why a service test was not included in TS 4.6.

Answer to Question 5: VRLA batteries have been used for as many as ten years in two UPS, unrelated to the UPS in the LAR, dedicated as backup power for the NCNR computers, experimental equipment, and data retention. The original and replacement battery banks have been replaced at intervals of greater than 5 years. Service records for these batteries show the banks have not degraded below their minimum capacity prior to replacement. In addition, of the 276 battery cells replaced during the three full bank replacements, 272 were in a satisfactory condition when replaced.

The VRLA battery banks do not warrant a service test because of:

• The small number of cell failures for a bank of VRLA battery cells.

• The number of VRLA battery cells.

• The increase in necessary battery power from a supply of 100 amps/hour for a load of 8 amps/hour to a supply of 100 amps/hour for a load of 4 amps/hour (see question 2 answer), i.e. a doubling of the cells available for the same load.

ATTACHMENT 1 BEFORE Configuration of UPS (battery charger) and Station Battery CY 0'

Ci 11 Z

< 0

-6 1-1

ATTACHMENT 1 AFTER Configuration of UPS, Battery Chargers, and Station Battery 0

94

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I I 1-2

ATTACHMENT 2 Annotated Excerpt from EATON 9390 UPS Installation and Operation Manual 7.1.2 Normal Mode - RT Figure 7-2 shows the path of electrical power through the UPS system when the UPS is operating in Normal mode.

Static K5Switch Off-site power or Rectifier Inverter emergency generator K1 AC AC DC Nuclear I Instrum ents Battery CMain Power Flow Breakers Contactors Trickle Current 66 -J- Closed Battery Breaker Energized o o -[open

_ _ _ _ De-Energized Battery Figure 7-2. Path of Current through the UPS in Normal Mode - RT During normal UPS operation, power for the system is derived from a utility input source through the rectifier input contactor K1. The front panel displays "Normal,"

indicating the incoming power is within voltage and frequency acceptance windows.

Three-phase AC input power is converted to DC using IGBT devices to produce a regulated DC voltage to the inverter. The battery is charged directly from the regulated rectifier output through a buck or boost DC converter, depending on whether the system is 208V, 380V, 400V, 415V, or 480V and the size of the battery string attached to the unit.

The battery converter derives its input from the regulated DC output of the rectifier and provides either a boosted or bucked regulated DC voltage charge current to the battery. The UPS monitors the battery charge condition and reports the status on the control panel. The battery is always connected to the UPS and ready to support the inverter should the utility input become unavailable.

The inverter produces a three-phase AC output to a customer's load without the use of a transformer. The inverter derives regulated DC from the rectifier and uses IGBT devices and pulse-width modulation (PWM) to produce a regulated and filtered AC output. The AC output of the inverter is delivered to the system output through the output contactor K3.

If the utility AC power is interrupted or is out of specification, the UPS automatically switches to Battery mode to support the critical load without interruption. When utility power returns, the UPS returns to Normal mode.

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ATTACHMENT 2 Annotated Excerpt from EATON 9390 UPS Installation and Operation Manual 7.1.5 Battery Mode - RT The UPS automatically transfers to Battery mode if the AC input is lost. In Battery mode, the battery provides emergency DC power that the inverter converts to AC power.

Figure 7-5 shows the path of electrical power through the UPS system when operating in Battery mode.

Static No Eý off-site power or Switch emergency generator power K1DC Rectifier Inverter AC K3 Nula Instrume nts Battery Converter IMain Power Flow

~

Breakers Jj-Closed Contactors Trickle Current C e CI Energized o o -[-Open De-Energized Battery discharging Figure 7-5. Path of Current through the UPS in Battery Mode - RT During a loss of AC, the rectifier no longer has an AC source from which to supply the DC output current required to support the inverter. The input contactor K1 opens and the battery instantaneously supplies energy to the battery converter. The converter either bucks or boosts the voltage so that the inverter can support the customer's load without interruption. If bypass is common with the rectifier input, the backfeed protection contactor K5 also opens. The opening of contactors K1 and K5 prevent system voltages from bleeding backwards through the static switch and rectifier snubber components and re-entering the input source.

While in Battery mode, the UPS sounds an audible horn, illuminates a visual indicator lamp on the front panel (System Normal, On Battery), and creates an entry into the alarm event history. As the battery discharges, the converter and inverter constantly make minute adjustments to maintain a steady output. The UPS remains in this operating mode until the input power to the rectifier is again within the specified voltage or frequency acceptance windows.

If the input power fails to return or is not within the acceptance windows required for normal operation, the battery continues discharging until a DC voltage level is reached where the inverter output can no longer support the connected loads. When this event occurs, the UPS issues another set of audible and visual alarms indicating SHUTDOWN IMMINENT. Unless the rectifier has a valid AC input soon, the output can be supported for only two minutes before the output of the system shuts down.

If the bypass source is available, the UPS transfers to bypass instead of shutting down.

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ATTACHMENT 2 Annotated Excerpt from EATON 9390 UPS Installation and Operation Manual If the UPS becomes overloaded or unavailable, the UPS switches to Bypass mode.

The UPS automatically returns to Normal mode when the overload condition is cleared and system operation is restored within specified limits.

If the UPS suffers an internal failure, it switches automatically to Bypass mode and remains in that mode until the failure is corrected and the UPS is back in service.

7.1.3 Bypass Mode - RT The UPS automatically switches to Bypass mode if it detects an overload, load fault, or internal failure. Figure 7-3 shows the path of electrical power through the UPS system when operating in Bypass mode.

The critical load is not protected while the UPS is inBypass mode.

AC AC Off-site power or through the standby UPS Nuclear K1 K3 Instruments SMain Power Flow Breakers Contactors Trickle Current

-W Closed Energized 0 0 -- Open De-Energized Figure 7-3. Path of Current through the UPS in Bypass Mode - RT 2-3

ATTACHMENT 3 Battery Charger SPECIFICATIONS (annotated)

Except as noted, all specifications apply at:

770 F / 250 C, nominal ac line voltage & nominal float voltage Specification Conditions 12 Vdc 24 Vdc 48 Vdc 130 Vdc Vac +10%, -12%

Output voltage regulation 0 to 100% load +/-0.25%

Temp. 32-1220 F / 0-501 C (see product literature for specific data)

Freq. 60 +/- 3 Hz 20-100% change, loadconnected Output voltage change +/- 4% maximum Transient response with battery Recovery to +/- 2.0% in 200 ms Recovery to +/- 0.5% in 500 ms Efficiency All ratings 82-90%

1%ms (typ.) 2% ms Unfiltered (with battery) at battery terminals 30 mV rms (max.) 100 mV Filtered (with battery) at ry tma ls Output ripple voltage (per NEMA PE5-1996) at battery terminals Filtered (without battery) 1% rms (typ.) 2% rms Battery Eliminator Filter 30 mV ms 100 mV Option (without battery) I Current Limit Iadjustable 50-110 % of rated output current Soft start 0 to 100% load 4 seconds Float 11.0-14.5 22.0-29.5 44.0-58.0 110-141 eEqualize Voltage adjustment rangesEqaie_____________ 11.7-16.0 23.4-32.0 46.8-61.0 117-149 High DC Voltage alarm 12-19 24-38 48-76 120-175 Low DC Voltage alarm 7-14.5 15-29.5 30-58 80-141 Voltmeter range (Vdc) 0-21 0-42 0 0-75 1 0-195 25 Adc nom. output 0 - 30 30-100 Adc nom. output 0 - 150 Ammeter range (Adc) 125-400 Adc nom. output 0- 500 500-800 Adc nom. output 0- 1000 1,000 Adc nom. output 0 - 1,200 Surge withstand capability test per ANSI C37.90.1-1989 no erroneous outputs Reverse current from ac input power failure, 90 mA maximum battery no options installed Audible noise average for four (4) sides, less than 65 dBA 5ft / 1.5m from enclosure Cooling natural convection Ambient temperature operating 32-1220 F / 0-50° C Elevation 3,000ft / 1,000m without derating Relative humidity 0 to 95% non-condensing Alarm relay contact rating 1120 Vac / 125 Vdc 0.5A resistive 3-1

ATTACHMENT 3 Battery Charger RECOMMENDED FLOAT AND EQUALIZE VOLTAGES (annotated)

This table contains suggested values for commonly used batteries. Consult your battery manufacturer's documentation for specific values and settings for your battery type.

Battery Cell Type Recommended Float Voltage/cell Recommended Equalize Voltage/cell Antimony (1.215 Sp. Gr.) 2.17 2.33 Antimony (1.250 Sp. Gr.) 2.20 2.33 I- Selenium (1.240 Sp. Gr.) 2.23 2.33 - 2.40

"* Calcium (1.215 Sp. Gr.) 2.25 2.33 Calcium (1.250 Sp. Gr.) 2.29 2.33

• , Absorbed / Gelled Electrolyte

• 2.25

• 2.25 (sealed lead-acid type)

Nickel-Cadmium (Ni-Cd) 1.42 1.47

• Sealed lead-acid battery types should not be used in ambient temperatures above 950 F / 350 C, and should not normally be equalized. Consult your battery manufacturer's documentation for specific equalizing recommendations.

TEMPERATURE COMPENSATION (annotated)

If your batteries are to see temperature variations during charging, a temperature compensation option (EJ5033-0#) is recommended. If this option is not part of your AT30, manual adjustments should be made. Refer to the equation and table below for temperature-adjusted voltages.

temperature-adjusted voltage = charge voltage x K Temperature Temperature K K (OF) (°C) (Lead-Acid) (Nickel-Cadmium) 35 1.7 1.058 1.044 45 7.2 1.044 1.034 55 12.8 1.031 1.023 65 18.3 1.017 1.013 75 23.9 1.003 1.002 77 25.0 1.000 1.000 85 29.4 0.989 0.992 95 35.0 0.975 0.981 105 40.6 0.961 0.970 3-2

ATTACHMENT 3 EATON 9390-40 Product Specifications (annotated)

The UPS systems are housed in free-standing cabinets with safety shields behind the doors. The UPS systems are available in 50/60 Hz with various output power ratings.

9390-40120 20 kVA 50/60 Hz 9390-40/30 30 kVA 50/60 Hz 9390-40/40 40 kVA 50/60 Hz 9390-80/40 40 kVA 50/60 Hz 9390-80/50 50 kVA 50/60 Hz 9390-80/60 60 kVA 50/60 Hz 9390-80/80 80 kVA 50/60 Hz The following sections detail the input, output, environmental, and battery specifications for the UPS.

UPS System Input Operating Input Voltage 208 Vac for operation from 177 Vac to 229 Vac (Nominal +10/-15%) 220 Vac for operation from 187 Vac to 242 Vac 380 Vac for operation from 223 Vac to 418 Vac 400 Vac for operation from 340 Vac to 440 Vac 415 Vac for operation from 353 Vac to 457 Vac 480 Vac for operation from 408 Vac to 528 Vac Operating Input Frequency +/-5 Hz Range Operating Input Current See Appendix A,Table H through Table J.

Reduced for Generator Adjustable Input Current Harmonic 5%THD at full load Content Power Factor Minimum 0.99 Line Surges 6 kV OC, 3 kA SC per ANSI 62.41 and IEC 801-4 Battery Voltage 384 Vdc (208V/220V units only) 432 Vdc 480 Vdc 3-3

ATrACHMENT 3 UPS System Output UPS Output Capacity 100% rated current Output Voltage Regulation +/-1-%(10% to 100% load)

Output Voltage Adjustment 208 Vac nominal, adjustable from 202 Vac to 214 Vac (Nominal +/-3%) 220 Vac nominal, adjustable from 214 Vac to 226 Vac 380 Vac nominal, adjustable from 369 Vac to 392 Vac 400 Vac nominal, adjustable from 388 Vac to 412 Vac 415 Vac nominal, adjustable from 403 Vac to 428 Vac 480 Vac nominal, adjustable from 466 Vac to 494 Vac Output Voltage Harmonic 1.5% max THD (linear load)

Content 5% max THD (nonlinear load)

Output Current See Appendix A, Table Hthrough Table J.

Output Voltage Balance 3% for 100% maximum load imbalance (linear load)

Output Voltage Phase 3' for 100% maximum load imbalance (linear load)

Displacement Output Transients +/- 5% for 100% load step or removal Frequency Regulation +/- 0.01 Hz free running Synchronous to Bypass Bypass within voltage limits of +5%, -8% of output setting; bypass within +/-0.5 Hz Frequency Slew Rate 1 Hz per second maximum Overload Current Capability 102% for 10 minutes 100-101.9%

110% for 30 seconds 102-109.9%

125% for 10 seconds 110-124.9%

>125% for 10 cycles Environmental Operating Temperature 0 to 40°C (32-104*F) without derating, excluding batteries. The recommended operating temperature is 25°C (77°F).

Operating Altitude Maximum 1500m (5000 ft) at 40°C without derating Storage Temperature -25 to +60*C, excluding batteries (prolonged storage above 40*C causes rapid battery self-discharge)

Relative Humidity (operating 5% to 95% maximum noncondensing and storage)

Acoustical Noise 65 dB at a Im distance, c weighted EMI Suppression EN62040-2:2006 CATC3 Electrostatic Discharge (ESD) Meets IEC 801-2 specifications. Withstands up to 25 kV pulse without Immunity damage and with no disturbance or adverse effect to the critical load.

3-4

ATTACHMENT 3 Eaton 12V 500W Battery (annotated)

Features

" Designed for high power density applications

" Small volume, lightweight discharge efficiency

" Can be used for more than 260 cycles at 100% discharge in cycle service

• UL-recognized components under UL924 and certified by ISO 9001 and ISO 14001

" Built to comply with IEC 896-2, DIN 473534 BS 6290 OT4, Eurobat

• Exclusive three-year battery parts coverage and one-year battery labor coverage CONSTANT POWER DISCHARGE CHARACTERISTICS: WATTS/CELL (77TF. 25°C)

End point volts/cell 5 min 7.5 min 10 min 15 min 20 min 30 min 40 min 50 min 60 min 90 min 1.85V 561 480 433 367 327 261 220 188 163 116 1.80V 638 557 492 416 356 276 232 198 171 122 1.75V 708 625 548 458 385 290 244 206 178 126 1.70V 773 685 602 489 404 305 251 210 181 127 1.67V 813 717 632 503 415 312 253 213 182 128 1.60V 879 782 695 530 432 325 260 215 185 131 All mentioned values are average values per battery per cell.

Tolerance: X <6 min (+15% - -15%), 6 min X <10 min 1+12%- -12%), 10 min X <60 min (+8% - -8%), X60 min (+5% - -5%)

DIMENSIONS [H x W x D, in (mm)]

13 50-0, r3f3432.5] -N 50 i-i K

12.83 i326r

- 4) ~1Ž. L=-._ --- _ . . _ ..

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I ATFACHMENT 3 Technical specifications Cells per unit 6 Voltage per unit 12 Capacity 500W @ 15-minute rate to 1.67V per cell @

771F (25°C)

Weight Approximately 100.75 lb (45.7 kg)

Maximum 800A (5 sec) discharge current Internal Approximately 3.7 mi resistance Operating Discharge: 5°F-122°F (-15°C-50°C) temperature Charge: 5°F-104°F (-15°C-40°C) range Storage: 5°F-104°F (-15°C-40°C)

Nominal 77°F +/- 5°F (25°C +/- 3°C) operating temperature range Float charging 13.5 to 13,8 Vdc/unit voltage Average at 77°F (25*C)

Recommended 50A maximum charging current limit Equalization and 14.4 to 15.0Vdc/unit cycle service Average at 77°F (25°C)

Self discharge Batteries can be stored for six months at 77°F (25°C).

Please charge batteries before using. For higher temperatures the time interval will be shorter. Voltage test prior to battery installation is recommended.

Terminal 12-thread lead alloy recessed terminal to accept M6 bolt Container Polypropylene UL94-VO/File E50955 material Flammability resistance of UL94-HB/File E216959 is available upon request.

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. I ATTACHMENT 4 Excerpt from Chapter 8, NBSR 14 8 Electrical Power Systems 8.1 Normal Electrical Power Systems 8.1.1 Design Basis These systems --i6are designed to supply all of the electrical power necessary to operate the NBSR during both normal and shutdown conditions. This includes all of the experiments, offices and other support spaces associated with the reactor. Electrical power is supplied to the NBSR by three independent, underground, 13.8 kV primary feeders (FA 1, FB 1, FC I). Each primary feeder is connected to a separate 13.8 kV/480V distribution transformer. The secondary of each transformer provides power to one of three specific sections of the main 480 V switchgear buss (913 A, SB3 B and SB C). -A substation independent of the three feeders provides power to the equipment in the Secondary Coolant Pump Building (SCPB) and the cooling tower cells equipment. Discussion efthis supply is limited to tS paragr.aph, as a secondary system failure

. ann. t cause a r.eactor, a.cident. Other major components of the electrical distribution system include two independent electrical generators-(A-af"d-B), battery power, two un-interruptible power supplies (UPS), two battery chargers, transformers, and associated distribution equipment.

The electrical generators are a source of emergency AC power and are independent of the NIST electrical distribution system. because a failure of the NIST system does not affect the reliability of the local generators- as a power sourced i.str.ibutin equipment and the fuel supply for- either gcner-ato engine. Battery power is provided by the station battery, described elsewhere in this chapter. The availability of multiple emergency power sources provides flexibility for operation of the facility in normal or emergency circumstances, but reactor safety requires only one operable backup power supply to The redundancy crf imRP@o*Ant la-ds and the protective s.heme ofthe bre,Ake.r.s in; teEcra Distr-ibutin System- prevent consequences from a,,y single equtipn failure exceeding those &EnFrom an accident causing a total loss of power for the rieaeer--systemsanalyzed in Chapter 13. -Therefore, while equipment and power sources have redundancy, redundancy is neither present nor necessary in the normal configuration of the facility distribution system.

As described below, the electrical distribution system consists of three major sub-systems: the Facility (or Building Services) Distribution System, the Reactor Distribution System and the Emergency Distribution System.

8.1.2 System Description 8.1.2.1 High Voltage Input [not applicable]

4-1

8.1.2.2 Facility Distribution System [not applicable]

8.1.2.3 Reactor and D-Wing Distribution System

[The first three paragraphs are not applicable.]

Off-site power provides AC power through the MAIN UPS to Critical Power Panel CP-1, which in turn supplies CP-2 and CP-3. The critical power panels supply power to the Reactor Control and Safety Systems. Normally, the STANDBY UPS is running and its output is directed to the main UPS reserve input.

Tables 8.4A, 8.4B and 8.4C list the loads on Critical Power Panels CP-l, CP-2 and CP-3, respectively.

Off-site power also provides AC power to maintain the lead-acid battery voltage and power to the DC loads on the 125 VDC Panel. Two battery chargers, one from MCCA-5 and one from MCCB-6, are load sharing devices and convert commercial AC power to DC power to provide a floating, or trickle, charge to the 125 VDC battery, and separately energize the 125 VDC panel.

The battery chargers are designed to work with the battery, which prevents a large temporary voltage drop from occurring on the 125 VDC panel if a large DC load is energized.

The 125 VDC Distribution Panel supplies power to two other DC panels: MCC DC (Table 8.21) which supplies Panel DCP-2: and Panel DCP-1. Tables 8.3A, 8.3B, and 8.3C list the loads on the 125 VDC Distribution Panel, DCP-1. and DCP-2, respectively.

8.1.2.4 Emergency Distribution System Em*..g.n.y Power-MCC A 5 is fed from ReaDt MCC .r A 3 thro.ugh Automati*

• irc.uit Br-eakc (ACG)* TN.1. E..erg.ncy Power- MCC 13 6 is fed fr- m Reae* D -MCC B3 4, through AC3 Ne. 4.

The two Emergency Power MCCs are tied together through a normally closed tie-breaker. The categorization of these motor control centers as emergency MCC is due to a single load, namely EF-5 on one MCC and EF-6 on the other MCC; both fan etoefs-blowers also can be powered from the DC buspanel.

The normal distribution lineup has ACB#Ne-.1 closed and ACBN#-No.4 open in stand-by. In this configuration, switchgear bus SB-AFA-I supplies both MCC A-5 and B-6 via Reactor MCC A-3. Since EF-5 and EF-6 are considered to be necessary for an emergency response, provisions are made to automatically provide emergency power to the two loads. An under-voltage device monitors the status voltageonf MCC A-5 and through the closed tie breaker, MCC B-6. If this device senses a loss of voltage, it automatically trips open ACB#N-.1 and closes ACB# No.-4.

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This transfers the feed for MCC A-5 and MCC B-6 to Switchgear Bus 8--BFB-1 via Reactor MCC B-4.

If power is not restored to MCC A-5 and MCC B-6, this same under-voltage device trips open ACB#No-. 4 and initiates the starting sequence of the emergency generators. Once a generator achieves the proper output frequency and voltageelectrical parameters, its associated Feeder Breaker, ACB#-N4e-2 for Emergency Generator A or ACB#--No.3 for Emergency Generator B, closes to restore power to MCC A-5 and MCC B-6. The generators are discussed in Section 8.2; Emergency 'Electrical Power- Systems.

MCC A 5 and MCC B 6 provide power tc all of the equipment necessary for the rector ina shutdown frsecured cendition. Table 8.2E lists the loads supplied by MCC A-5 while Table 8.2F lists the loads supplied by MCC B-6.

Dur-ing normffal operation, either the T 9 Reactor UPS or-the T: 10 Reacter- UPS supplicsA f)EAA- F......  : ,A YTfe aR*

• Rt,÷ Y. WAR..... HSW

• S1 . . ... . WW c a. . Ey u Ic ef the toe 20 1IPS will -And-cndition Uonvet the supplied-commercwial AC pnerrp to ay the lads of the 125r VDC bus and provide a floating, oftrihkle,mharge to the statien battery. The ether UPS is energized, but not on line and aCts as an installed spare. The Critical Power Panels supply pofer to the Reaitn r nattryl and Safety Systems. Tables 8 poA, 8.4i and 8.46 list the loads onf Criti4c-Al Poweipr Pnl CUP 1, CP 2 and GP 3, r-espectively. The 125 VDC Distr-ibution Panel -alsosupplies pewer to twoe other PC panels, MCC PC (Table 8.21) whieh supplies Panel DCP 2, and Panel DCP 1. Tables 8.3A, 8.313, and 8.3C list the loads ont the 125 VDC Distr-ibution Panel, Panel DCP 1, and DCP 2 r-espectively.

The sequence of power transfers involving the UPS to maintain power without interruption to CP-1. starting with a normal reactor electrical distribution configuration. is as follows:

I. If AC power from MCC B-6 is lost to the input of the main UPS. then the battery bank for the main UPS would provide AC power to CP- 1.

2. After the main UPS battery bank is depleted, the standby UPS Provides AC Power to CP-lI througzh the reserve input of the main UPS. If AC power is restored to MCC B-6 and the main UPS battery bank is not depleted and the main UPS has not triPped on a fault, then the main UPS would retumn to service automatically.

3. If AC power from MCC A-5 is lost to the standby UPS. then the battery bank for the standby bank would provide AC power to the main UPS reserve input. If AC power is restored to MCC A-5 and the main UPS battery bank is not depleted and the standby UPS has not tripped on a fault, then the standby UPS would return to service automatically and provide AC power to the reserve input of the main UPS.

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4. After the standby UPS battery bank is depleted and after AC power is restored to MCC A-5, unfiltered AC power will be directed through the standby UPS to the reserve input of the main UPS.

if AG poer iF klest to the input of the on; linRe UPS, batterzy power-automatically supplies the loads on the 125 VD. DiStribution.. Panel and the Citieal Pwer Panel leads. When AC p.wer is r-estored, either frmn the emer~geny generatr-Or fr6M another SOure, the UPS autmte ially resumes char-ging the station battery, and the UPS -eautomiatic-ally r-esumnes supplying power to the Critical Power Panel and the 125 V-DC Distributicn Pmnel.lf AC power is lost to the input of both battery chargers, the trickle charge to the sixty cell lead acid battery bank would cease and that battery bank would assume the loads on the 125 VDC panel for at least 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. After AC power is restored, the primary battery charger resumes charging the battery bank.

Emergency Lighting Panels X-1 and X-2 supply selected lights with either AC power or DC power. Panel X- 1 powers emergency lights in the office spaces in the A- and B-wings.

Normally, this panel receives AC power from CP-3. Upon loss of AC power, automatic transfer switch TS- 1 transfers the feed from CP-3 to DCP- 1. Panel X-2 powers emergency lights in the Confinement Building. Normally, this panel receives AC power from MCC A-5 via Miscellaneous Power Panel P-5, located on MCC A-5. Upon loss of AC power, an automatic transfer switch transfers the feed from MCC A-5 to DCP-1.

A simplified diagram of the Emergency Distribution System bussing arrangement is shown in Figure 8-2.

8.1.3 Electrical Power Capability [not applicable]

8.1.4 Codes and Standards [not applicable]

8.1.5 Lightning Protection [not applicable]

8.1.6 Grounding [not applicable]

8.2 Emergency Electrical Power Sources 8.2.1 Design Basis Emergency electrical power is designed to provide power to the nuclear instruments and the emergency exhaust fans should a complete loss of off-site power occur. One of the two emergency generators is capable of supplying power to all necessary emergency equipment.

Battery power is also capable of independently supplying the vital loads for a minimum of four hours. By requiring the operability of at least one emergency generator during reactor oNeration and requiring the availability of battery power during reactor operation, power sources will always be available for an emergency response.

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8.2.2 System Description This system consists of:

a. [not applicable]

b. The station battery- is composed of three battery banks, two of which would be in service in a loss of AC power scenario. which eombinOne bank is made up of sixty, two volt, lead-acid type baaefy eellsbattery cells to produce a single output of 125 VDC with a capacity of 880 amp-hours. The other two banks comprise the emergency AC backup capability of the two UPS. One bank would be in-service, and the other bank would be in standby. Each bank is made up of valve-regulated lead-acid (VRLA) battery cells.

.~ .*125*otPC bus which can supply power to"thle Vital lJoAds for emergency situations.

The w bus an be iutput.

energized via the PC Of either f the 20 kV.A IUPS or output of the staicn battery.

In case of a total loss of off-site power and emergency generator AC power, vital equipment would remain energized for at least four hours: EF-5 and EF-6 DC powered fans, controls, and associated valves, and nuclear instrumentation. Non-vital equipment on the critical power panels and the DC bus would remain powered for at least four hours, unless de-energized with individual controls, e.g. a local breaker. That equipment includes process instrumentation, AC and DC valve control power, effluent monitors, other critical power panel loads (see Chapter 7),

and the reactor shim arm control. the 125 - D bus w..ouldremain enerized for l oad classified as rveator-emcrgeney equipment. These circeumstanees would require a DG power-sourcee and the station batetery serveOS a;s,t-he- W sourcee to carr-y the elmerec equIp..."ment loaRds -f-r- eight.

heursstai bIttr ý a ssuming the cuiten t nceds fa r all oIf the equipment would equal approximately 100 amps, plus the amfperaige required by an operaiting 20 kVA UPS. Ti equipment includes the following:- vital equipment (Emnergency Ventilation Sy'stem DC powered r~~~ nn ~rnt'rIhDn.7n r" Pnrn hweteF (T-9 mode or Tl 0 mode), the reaete instrumentation.

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Table 8.1A, B, C [not applicable] and Table 8.2A, B, C, D [not applicable]

Table 8.2E: Load List MCC A-5, Emergency Power Cubicle Load 1B Breaker Interface Module (BIM) & Central Monitoring Unit (CMU) 1E TVSS 1G D20 Storage Tank Pump DP-7 I iJ T-4OStandby UPS 1M SCV-50 2A Door (Future) 2F Miscellaneous Power Panel A5 2HL Primary 2HR Secondary 2M 15 kVA Transformer 3B Helium Blower HB-1 3D EF-3 3F EF-4 3HL Elev. & Door Cont. Power 3HR Reactor Door Panel P8, P9 3K Rabbit Blower 3ML Feeder Control Air Compressor No. 2, Battery Charger 2 3MR Spare 4B D20 Experimental Booster Pump DP-9 4E D20 Shutdown Pump DP-5 4G Secondary Cooling Shutdown Pump 4J Sump Pump to Hot Waste 4LL DWV-2 4LR Spare 4M Door (Future) 5B Thermal Column Pump No. 1 5D Demin. Water Exp. Cooling Pump No. 1 5G Thermal Shield Circ. Pump No. 1 5M Feeder Reactor MCC A-3 6C Subfeed Lugs to MCC B-6 6G Relay Panel 6H Door (Future) 6M Feeder Emergency Generator A 4-6

Table 8.2F: Load List MCC B-6, Emergency Power Cubicle Load 1E Feed From MCC A-5 1H Relay Panel 1M Feeder Emergency Generator B 2B D20 Experimental Booster Pump DP-10 2D Demin. Water Exp. Cooling Pump No. 2 2G Thermal Shield Circ. Pump No. 2 2H Door (Future) 2M Feeder Reactor MCC B-4 3A Hot Waste Sump Pumps 1A & 1B 3D D20 Shutdown Pump DP-6 3FL T--Main UPS, Battery Charger 1 3FR Spare 3H Emergency Sump Pump 3KL Feeder Control Air Compressor No. 1 3KR DWV-1 3ML Spare 3MR Spare 4B Tritium Blower 4D Recirculation Supply Fan SF-19 4F Dilution Exhaust Fan EF-2 4H Hood Exhaust Fan EF-23 4K Spare 4M D20 Storage Tank Pump DP-8 5C DWV-19 5E Helium Blower HB-2 5J Thermal Column Pump No. 2 5M TVSS Table 8.2G: Load List MCC DC Cubicle Load A-1 DC Power Panel 2 (DCP-2)

B-1 Exhaust Fan EF-5 (DC Motor)

C-1 Exhaust Fan EF-6 (DC Motor)

D-1 Exhaust Fan EF-5 (AC Motor)

E-1 Exhaust Fan EF-6 (AC Motor)

A-3 D20 Shutdown Pumps DP-5 B-3 D20 Shutdown Pumps DP-6 4-7

Table 8.3A, B, C [not applicable] and Table 8.4A, B, C, D [not applicable]

Figure 8.1: Simplified Diagram - High Voltage Input Switchgear and Bussing Arrangement [not I applicable]

Figure 8.2: Simplified One-Line Diagram for the Reactor and Emergency Power Distribution System (Normal/Preferred Lineup, Essential, and Vital Loads) [See page 2 of Attachment 1]

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