ML15167A070

NIST - Annual Preventative Maintenance Inspection Report

ML15167A070
Person / Time
Site:	National Bureau of Standards Reactor
Issue date:	06/12/2015
From:	Eaton Corp
To:	Document Control Desk, Office of Nuclear Reactor Regulation
Shared Package
ML15167A064	List: ML15167A069 ML15167A070
References
2390504, ED042CAB06
Download: ML15167A070 (16)

Text

ANNUAL PREVENTATIVE MAINTENANCE INSPECTION REPORT Inspection Performed: 04/0812014 Ticket Number: 2390504 Serial Number: ED042CAB06 NATIONAL INSTITUTE OF STANDARD 100 BUREAU DRIVE GAITHERSBURG, MD 20899 Attention: DENNIS BRADY Phone: 3019756264 Battery Services Performed By:

E-IzT.N Allen L. Fowler Battery Ops Manager Six Forks Road, Raleigh, NC 27615 Phone: 919-730-5744 E-mail: AllenLFowler@eaton.com Service Dispatch: (800)843-9433 www.powerware.com page:l

NATIONAL INSTITUTE OF STANDARD ANNUAL PREVENTATIVE MAINTENANCE INSPECTION REPORT Date: 04/08/2014 Green - No Problems Found.

D No repairs performed.

Service Description VRLAISEALED

'Charge output current and voltage AC ripple voltw 0% Open CW*,r Vle 0% Float C.W/Jar Voltae C~ voltage Intemi rnetwsanempedance 0% of Inter-cell connection reistances ReP-orue as neceseew Ambient temperature Temperature of negative terminal 0 % of specifc gravity (flooded cels)

Visual bnwpecdon Inspect ventlati_

inspect battery monitoring equipment Load Teat performed ALL UNITS TESTED WITHIN MANUFACTURER'S SPECIFICATIONS.

E:'[.N page:2

NATIONAL INSTITUTE OF STANDARD ANNUAL PREVENTATIVE MAINTENANCE INSPECTION REPORT Date: 04/08/2014 UPS Mfr Eaton UPS Serial: ED042CAB06 UPS Model: 9390 -80 80 Charger Qty: 1 Battery Mfr: EATON Battery Type: Sealed Battery Model: PWHRi2390W4FR Mfr. Date: 11/2009 String ~a r Ity:o1mStriongIotinYe DC Lnk Nominal: 540 Fixture Type: Tray Trays per String : 9 Jars per Tray: 4 String Qty: 1 String Isolation: Yes Seismic Rating: Cycle Counterd None System Float Voltage: 497.0 System Float Charging Amps: 0.0 System Equalize Voltage: 0.0 Charger AC Ripple Voltage: 1.53 Charger AC Ripple Current: 4.0 Room Temperature ( Fahrenheit): 73.0 Rack/Cabinet Condition: Good System Load: 11.0P  % Total Electrolyte Vol:

Positive Voltage to Ground: 107.9 Negative Voltage to Ground: 390.0 Retorque Connections: No Recommended Value:

Value Used:

Fire Suppression: Not Tested Spill Kit: Not Present Eye Wash Station: Not Present Hydrogen Detector: Not Present Shower Not Present Vent Fan: Not Tested Spill Containment: Not Present Lighting: Not Tested Minimum Maximum Test Typ Wam1n8 Warning Voltage Float 12.840 12.840 14.500 14.500 Voltage Open 12.840 12.840 14.500 14.500 Specific Gravity Neg Post Temp. 68.000 70.000 84.000 86.000 Cell Temp.

Ohmic 1000.000 1000.000 Resistance 5300.000 5521.000 FIT.N page:3

NATIONAL INSTITUTE OF STANDARD ANNUAL PREVENTATIVE MAINTENANCE INSPECTION REPORT Date: 04/08/2014 Charger Mfr: Eaton Battery Mfr: EATON Model: 9390 - 80 / 80 Model: PWHR12390W4FR Serial #: ED042CAB06 String 1 Volts Load Specific Micro-Ohms Inter Unit Float Open Open End Resistance Temp Gravity Post I Post 2 Post 3 Tier Status Tray 1 OK Jar 1 13.157 4561.000 375.000 OK Jar 2 13.103 4425.000 866.000 OK Jar 3 13.130 4317.000 383.000 OK Jar 4 13.102 4353.000 73.0 22.000 OK Tray 2 1 - OK Jar 1 13.085 4434.000 512.000 1 OK Jar 2 13.072 4240.000 473.000 OK Jar 3 13.134 4344.000 384.000 OK Jar4 13.105 4355.000 73.0 105.000 OK Tray 3 OK Jar 1 13.095 1 4411.000 333.000 OK Jar 2 13.093 4382.000 392.000 1 OK Jar 3 13.125 4378.000 371.000 OK Jar 4 13.100 4375.000 73.0 122.000 OK Tray 4 OK Jar 1 13.077 4368.000 440.000 OK Jar 2 13.097 4337.000 545.000 OK Jar 3 13.105 4384.000 423.000 1 OK Jar 4 13.179 4385.000 73.0 147.000 OK Tray 5 OK Jar 1 13.163 4437.000 372.000 OK Jar 2 13.196 4322.000 418.000 OK Jar 3 13.105 4399.000 452.000 OK Jar4 13.175 4368.000 73.0 51.000 OK Tray 6 OK Jar 1 13.119 4487.000 343.000 OK Jar 2 13.112 4399.000 448.000 OK Jar 3 12.966 5233.000 401.000 OK Jar 4 13.115 4265.000 73.0 44.000 OK Tray 7 OK Jar 1 13.094 4401.000 333.000 OK Jar 2 13.103 4372.000 390.000 OK Jar 3 13.115 4502.000 341.000 OK Jar 4 13.079 4382.000 73.0 66.000 OK Tray 8 1 1_1_OK Jar 1 13.112 4409.000 342.000 OK Jar 2 13.068 4434.000 429.000 OK Jar 3 13.111 4444.000 368.000 OK Jar4 13.125 4481.000 73.0 36.000 OK FWT.N page:4

NATIONAL INSTITUTE OF STANDARD ANNUAL PREVENTATIVE MAINTENANCE INSPECTION REPORT Date: 04/08/2014 Charger Mfr: Eaton Battery Mfr: EATON Model: 9390 - 80 / 80 Model: PWHR1239OW4FR Serial #: ED042CAB06 String I Volts Load I specific Micro-Ohms Inter Unit Float Open Open End Resistance Temp Gravity Post I Post 2 Post 3 Tier Status Tray 9 OK Jar 1 13.145 4459.000 349.000 OK Jar 2 13.181 4427.000 386.000 OK Jar 3 13.135 4310.000 422.000 OK Jar4 13.134 4437.000 1 73.0 - 1 159.000 OK

]

"Eaton Power Quality Corporation offers maintenance and I replacement services on ALL types of Battery Systems - UPS, Telecommunications, Industrial, etc. For more information contact your local represenative."

F.T*N page:5

NATIONAL INSTITUTE OF STANDARD ANNUAL PREVENTATIVE MAINTENANCE INSPECTION REPORT Date: 04/08/2014 Resistance Graphical Representation 50 0 . ..... .... .. .. .... .. . .... .. ........ ..... ..... ... ... .. . ... . . . . . . ...... . ...... . -... ... .. . . . .. ... ..

$0 0 . .............. ..... ... ......... ...... .......... . ... .. ....... . .. . . ........ . ........... ... ..... ... ... ... ... . .... ...... ..-

30 0 -.. .. . . .. . .. . . .. . .. . . .. . .. . . .. . .. . . .. .. . .... . .....

700 300..

500 . ... ...... .... . ... .

00 700 . ..... ..

300 ---

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(500

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. .. . . .... ....I... ... ...... ... .

30 0 . ....... ...... . ...... ... .. ..... .

0 1 2 3 4 5 6 7 8 9 10 1112 1314 1516 1718 19 202122 2324 275262728 _.930 3132 33 34 35 36 37

] a Resistance - Resistance Average IF.'TN page:6

Supplementary Response to RAI Questions 3 and 5 This supplement expands the NCNR response of February 26, 2015, to RAI Questions 3 and 5 (please see Attachment 1) of January 30, 2015. Specifically, this response will clarify the NCNR commitment to VRLA battery maintenance to justify battery bank measurements in lieu of battery measurements, thus ensuring the emergency power capacity to meet the station battery duty cycle.

In the June 23, 2014 license amendment request, the NCNR committed to meeting the VRLA battery maintenance guidance found in the UPS owner manual and committed to following the performance test recommendation found in IEEE 1188-2005. The structure of the paragraph with those commitments clearly obligates the NCNR to complete the 2 year performance test described in the standard with satisfactory results, and to nothing else in the standard.

The commitment to only the 2 year test is consistent with previous NCNR technical specification surveillances described in the following paragraph. Commitment to the guidance in in the UPS owner manual will be demonstrated through a semi-annual or annual service that records selected parameters for each battery during a partial loading of that battery. The condition of each battery will be defined as pass or fail based upon the data collected and the effect of failed batteries upon bank capacity will be assessed, followed by battery replacement or additional monitoring. See Attachment 4 for a summary of the data.

Per Technical Specification (TS) 3.6, confirming ". . . the station battery. . . operable, including associated distribution equipment. . ," not individual battery capacity, is the objective of the emergency power technical specification in order to maintain power to specific equipment for a given period of time, assuring the assumptions of the safety analyses (NBSR 14, 2009) remain valid and other technical specifications, e.g. confinement integrity, are met (NBSR 15, 2009).

TS 3.6 requires the station battery to be operable, i.e. have the capability to supply power to the nuclear instrumentation and the emergency exhaust fans for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

ANSI/ANS-15.1-2007 The Development of Technical Specificationsfor Research Reactors defines operable as, "Operable means a component or system is capable of performing its intended function." The component or system here is the station battery, which consists of 60 single-cell wet batteries in series and 72 multi-cell VRLA batteries (see Attachment 2), 36 of which are in series, with two 36 battery groups in parallel to generate the proper voltage with the required current for the minimum time. Only a bank of batteries can fulfill the intended function described in TS 3.6. Note that the previous station battery was also a bank of batteries. The design philosophy was, as it is now, to have an excess of batteries that allows the battery bank to meet bank duty cycle. Consistent with this design is the assertion that a single battery failure which does not interrupt the electrical circuit of the battery does not constitute component failure. Other examples from NBSR license documents of this approach are: Total coolant flow is specified, not the number of coolant pumps (NBSR 15, 2009); total reactor power is limited,

not power per fuel assembly (TR-5, 2009). Certainly a bank of batteries with the exact number of batteries necessary to meet the station battery duty cycle could not sustain a single battery failure; the NCNR has rejected that design through three operating license renewals over the previous 40 years.

A surplus of batteries is also consistent with the single failure analysis and defense-in-depth approach to reactor safety (NUREG 1537, 2012) used by research and test reactors licensed by the NRC. A common mode failure originating from improper charging voltage for every battery in the bank is addressed through the battery monitoring system that is integral to the UPS.

Designated "ABM Technology" (ABM) by the UPS manufacturer, the ABM monitors bank parameters to continuously assess the bank condition and produces notices and alarms if the parameters are found to be abnormal. Local alarms produce a single remote alarm in the Control Room. Notices indicate a potential problem and alarms indicate an impending UPS shutdown, if additional action is not taken. Additionally, the ABM controls the charging scheme for the UPS battery bank. The ABM charges the battery bank, applies a float charge for approximately a day, performs two tests, secures the float charge for 28 days, and produces an estimate of battery bank service life for the design load of the UPS, i.e. 20 KVA. The manufacturer claims increased lifetime for a battery charged in the manner described above.

Their claim is based upon 22 years of data and observation.

The design load is programed during the setup of the ABM based on the capacity of the installed battery bank. The design load is twice the normal load that is presently being supplied by the UPS. If conditions were such that the UPS had to supply the power from the battery bank, the ABM estimates the battery bank service life based on the actual load. The required load specified in the Limiting Conditions for Operation (LCO) for emergency power, TS 3.6, i.e.

the nuclear instrumentation and the emergency exhaust fans, is significantly less than the normal load. In an emergency, with the battery bank supplying the power, the service life could be greatly extended by shedding the load to only what is required by the LCO. See Attachment 3 for a detailed description of the ABM.

To summarize, the NCNR has a proven approach to surveillance and maintenance for LCO as described in ANSI/ANS-15.1-2007. That approach is applied to the VRLA battery banks through alarms and notices (continuous), bank life estimate (monthly), individual battery service (semi-annual or annual), and a performance test (2 years) ensure the station battery duty cycle will be met.

ATTACHMENT 1 NRC Email Message of May 7, 2015 In response to RAI Question 3, the licensee stated the following: "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. [...]. A two year discharge test is sufficient to reveal failing or failed battery cells." As recommended by IEEE Std. 1188-2005, the VRLA battery cell voltage should be checked periodically because prolonged operation of cells below or above the manufacturer's recommended voltage limits can reduce the life expectancy of the cells or have a detrimental effect (e.g., accelerated dryout) on the battery. In addition, a cell voltage consistently below normal float conditions and not caused by elevated temperature of the cell indicates internal cell problems that may require cell replacement.

In response to RAI Question 5, the licensee stated that the VRLA battery will not be subjected to a service test because of (1) the small number of cell failures for a bank of VRLA battery cells, (2) the number of VRLA battery cells, (3) 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 (i.e., a doubling of the cells available for the same load). IEEE Std. 1188-2005 recommends the performance of a service test to determine the battery's ability to satisfy the design requirements (battery duty cycle) of the dc system in the as found condition. The staff notes that the VRLA battery having double of the cells available for the same load does not guarantee it meeting its duty cycle at all times. A periodic service test is needed to ensure the battery meets its duty cycle.

ATTACHMENT 2 Description of VRLA Battery A VRLA cell is the manufacturer's term for the 6 sets of plates that make up the single VRLA battery used in the EATON 9390 UPS in service at the NCNR to provide emergency power to selected AC loads. For this unit, the terms battery cell and battery are not synonymous, as they are for the wet-cell units that make up the battery bank which provides emergency power to selected DC loads. Battery bank or station battery refers to a group of batteries that are connected in series to provide a specified voltage.

Positive flag Extruded intercell Valve terminal welded connection, low resistance

. current path Cover/lid Strap joining negative plates in parallel

~Negative pasted plate lead alloy grid Polypropylene container/jar Separator Internal and external components of a valve-regulated lead-acid MRLA) battery.

The Uninterruptible Power Supply (UPS) battery bank comprises two groups of batteries, each group in parallel, and each group comprising 36 batteries in series. There are two UPS, each with 72 batteries.

The battery has a 10 year design life and a 3 year warranty. The minimum voltage for a battery to be considered operable by the manufacturer is 10.02 volts (1.67 V/cell x 6 cells). The minimum voltage for a battery bank to be considered operable by the manufacturer is 360.07 volts (36 batteries x 10.02 V/battery).

The normal voltage of the battery bank is approximately 478 volts. Individual battery failure would be revealed by the battery monitoring system described in Attachment 3. Estimates of lifetime assume no damage to the circuit, such as could occur with thermal runaway, a condition that can result from dryout. The monitoring system, as well as previously described surveillance and maintenance activities, would provide indication of a potential dryout condition. Note that the NCNR does not limit the definition of operable only to output voltage. The bank must generate the proper voltage and have an expected lifetime of at least 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> for the specified AC loads. The battery monitoring system for the 9390 UPS provides an estimate of the bank lifetime.

ATTACHMENT 3 Description of Battery Monitoring System IFMeN Powering Business Worldwide mehia ABM Technology and Battery Testing in Eaton UPS Products Introduction The battery system in a UPS represents the heart of the power protection benefit. This key element performs two functions: (1) it delivers energy during a power outage, and (2) it stores energy efficiently for extended periods of time. That stored energy is instantaneously available when needed to support the critical load on the UPS. In order to perform the above functions reliably, the charge level of the battery must be maintained. At the same time, battery charging should be controlled to maximize system efficiency and, more importantly, to maximize the float service life of the battery system.

The unfortunate fact is that Valve Regulated Lead Acid (VRLA) batteries are often marketed as having a 10-year design life. However, real world data shows that in UPS applications, the battery is replaced every four to five years on average. Because the battery often accounts for 30% of the cost of the UPS, users frequently request that UPS vendors extend the service life of the battery as much as possible.

Considering that the benefit of longer service life is lower life cycle cost and capital expense, it is not surprising that users desire tangible evidence that battery monitoring and battery management systems actually perform as advertised.

Two types of battery charging schemes have traditionally been used for UPS battery systems. The older and more commonly known is the "float" charge, which involves applying a constant voltage charge to the battery continuously for purposes of maintaining full charge during day-to-day operation of the UPS. This works quite well in many conventional battery applications. However, battery life may not be optimal, due to overcharging, for batteries that are used very occasionally as in standby applications such as a UPS. In a UPS, the battery system may sit in float mode for many months, without ever experiencing a discharge.

Float charging for long periods of time means that "trickle-charge" energy is constantly forced into a battery which is effectively already full. This results in very gradual degradation of the lead plates (positive grid corrosion), and it can impact float service life.

Standby applications are better suited for "opportunistic" charging schemes. The system Eatonutilizes is called ABM technology, which is essentially a set of charger controls and automated battery tests. It is implemented in Eaton single-phase UPSs from 500 VA to 18 kVA and three-phase models from 10 kVA to 3.3 MVA. Opportunistic charging schemes like ABM allow for periods of time where the battery is being fully charged, and periods of time when the charger is disabled. This reduces the time that the battery is subject to grid corrosion when compared to a traditional float charger - a reduction in grid corrosion that yields a measurable increase in battery life for UPS applications.

ABM Operational Summary As shown graphically in Figure 1, ABM consists of three operating modes:

1) Charge mode

2) Rest mode

3) Test mode

Charge Mode ABM Float Mode Rest Mode 2 3..................... ..... . . T ........

"6

• Batter), Test 2

~45 sec

....... --- - - - 4..........

<10dayso 2 .1 ... --- - .. -

I I I 24Hrs I I I I 100Hrs Max 48Hrs - 96Hrs 28days 4 to s Figure 1: Depiction of ABM modes Charge Mode The UPS enters the charge mode under any of the following conditions:

• Whenever the UPS is commanded to turn on

• After any utility power outage lasting longer than 15 seconds

" Whenever the battery is replaced (or the battery breaker is opened and re-closed)

In charge mode, constant voltage charging of the batteries is used to recharge a discharged battery after a power outage, or whenever the ABM process is restarted. Charge voltage target is set to the manufacturers' float level, and charge current is greater than 0.1 C A. Constant voltage charging lasts only as long as it takes to bring the battery system up to a predetermined float level (there is a 100-hour maximum time limit). Once this level is reached, the UPS battery charger remains in constant voltage mode, maintaining a float level. The current is at trickle-charge levels during this time, and a 24-hour clock is started. At the end of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of float charging, the UPS automatically performs a battery test (see Figure 1) at two different load levels to verify that the battery is performing, and to collect data for comparison to previous and subsequent automatic battery tests. Ifthe test fails, an alarm is activated on the UPS and also through the remote monitoring system that may be connected to the UPS. At the end of the test, the charger resumes constant voltage mode and remains in that state for an additional 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Rest Mode Rest mode begins at the end of charge mode; that is, after 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of float charging, and after a successful battery test. In rest mode, the battery charger is completely turned off. The battery system receives no charge current during this mode, which lasts about 28 days. Then, the charge mode is repeated as described above. Since the battery clearly spends most of its time in rest mode, as a result, the following benefits are realized:

1) The battery is not subjected to constant forced charge current; therefore, overcharging is not possible.

2) Thermal runaway is not a concern with the charger off.

3) The battery system cannot be damaged by ripple currents, since the charger is off.

4) Positive grid corrosion is greatly reduced, allowing extended service life.

During rest mode, the open circuit battery voltage is monitored constantly, and battery charging is initiated if any of the following occur:

" A power outage lasting longer than 15 seconds

" The open circuit voltage (OCV) of the battery drops below a predetermined threshold after 10 days of rest mode (If OCV drops below the predetermined threshold during the first 10 days, an alarm is triggered)

• 28-day timer expires (end of rest mode)

• The battery is replaced, or the breaker is opened and re-closed Test Mode There are two other battery tests that are performed as a part of the ABM cycle. The first is meant to detect battery conditions which could lead to thermal runaway. The bulk charging period is timed and ifthe float voltage is not reached in a predetermined time, an alarm is triggered and the charger is shut down.

The second test is performed after the charge cycle is completed (i.e., at the beginning of rest mode). The battery is discharged for 25% of the expected discharge time. Upon reaching this point, the battery voltage is measured. If the voltage is below a specified threshold, dependent on the load, then an alarm is signaled indicating the battery is nearing the end of its service life and should be replaced.

Other Modes ABM may be disabled by the user or an Eaton field technician at any time. In this case, the UPS battery charger operates as a conventional float charger only. This is recommended when a wet cell or flooded electrolyte battery is used with the UPS. ABM is intended for use with VRLA batteries. As a result, wet batteries do not benefit from ABM controls.

Many observers express concern regarding the ability for the battery to maintain capacity if called upon to support the UPS near the end of its rest mode. In other words, how much battery capacity is available on day 27 of a 28-day rest mode? Using a 15-minute battery as an example, under this condition, the battery would provide all but about 30 seconds of its 15-minute backup time. This is proportionally true for other battery sizes, as well. The intent in selecting the 28 day rest period is to limit the loss of capacity to approximately 5%.

ABM Performance The ABM process above describes the benefits of using a "opportunistic" charging scheme. Those benefits, specifically extended service life, are in fact substantiated by data and empirical testing performed by Eaton as well as other independent sources. Some of this testing is recent and some of it was performed as many as 20 years ago.

ABM is not a new battery management feature. In fact, Eaton has been using ABM in its UPS products for 22 years, and it has proven itself beneficial in the field for more than two decades.

Battery Life Data 9

8 7

E 6 0

E 5 - ABcIe 4F-Trickle 06 4 3

2 1

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Time in test, months Figure 2: Accelerated Life Testing of ABM at 40 degrees C In Figure 2, the testing was performed at a very high ambient temperature to provide meaningful data in a shorter period of time. The service life enhancements become evident after about only seven months of this accelerated test. This test was done with conventional UPSs and VRLA batteries.

Battery Life Test 14 12 10 d

E 0 8 E Cyclic C--

0. -a- Float 6

4 2

0 0 6 12 18 24 30 36 42 48 54 60 66 Time In test, months Figure 3: Long Term Cyclic Charge vs. Float Test In Figure 3, the effect of a cyclic charging regime over several years is demonstrated. This testing was done almost 20 years ago, by a battery manufacturer not associated with Eaton or any UPS vendor.

Life Expectancy For .... Charge Algorlthm N. _2123 days

3. 3123days 4123 days 6 t55123 days I~ 6123 days 2 12123 day 23123 days 2S 30 35 40 45 50 Temperature I C

-a-23/23days -a--12/23days -- 8/23days -- 85/23 days

-'-4/23 days , --- 3/23 days ---- 2/23 days I Figure 4: Calculated Service Life Extension for ABM Charge Algorithm Note that in Figure 4, the curve identified as "23/23 days" represents a float charger, and ABM (as implemented today) is best represented by the curve labeled "12/23 days." At an ideal 25 0 C (770F), there is a theoretical increase of six years in battery service life reflected in this analysis.

The above information shows a clear benefit of cyclic charging in UPS applications,both in simulated and in actual performance tests. These results would not be expected with non-VRLA batteries or in applications such as motive power chargers where the battery is discharged/recharged daily and therefore not deployed in a standby application.

Summary ABM is unique in the UPS industry, but similar opportunistic designs are utilized by battery manufacturers and battery charger designers worldwide. The criticality and cost of the battery subsystem of any UPS dictates that special consideration be given to battery longevity. Additionally, with environmental concerns relating to battery removal and disposal becoming more prevalent, it is desirable to reduce the frequency of battery replacements during the life of the UPS electronics. ABM offers a significant benefit over conventional "battery monitors" which don't provide charging control, and "multi-stage chargers" which protect the battery, but do not provide useful extension of battery service life.

Over the past 22 years, ABM has proven itself in both large and small UPS products, from the desktop to the data center, and from the medical lab to the factory floor. Anywhere a UPS is installed, a battery system is depended upon to provide backup power protection for critical business processes and even for personnel safety. The battery is all too often ignored as a maintenance-free product, not requiring attention or inspection. This neglect, though common, can be costly and possibly disastrous. The ABM system, by its nature, helps to provide early detection of problem batteries and thus protect the battery from unnecessary failures like electrolyte dry out and thermal runaway, while functioning to extend the useful life of this key component of power quality.

SUMMARY

OF VRLA BATTERY INSPECTiON DATA FOR NCNR UPS Battery Inspection Specifications Range Impedance Range Range Post 1 Resistance Range 12.840 - 14.5 V _1 5048.871 Ohm 174 - 80 OF 0- 300 lOhm I UPS Unit Date ]Status of Batteries Action Status of Bank UPS-1 2005-04 120 New Batteries All batteries replaced OK UPS-1 2006-07-06 120/120 Batteries OK None OK UPS-1 2007-04-07 120/120 Batteries OK None OK UPS-1 2010-07-15 119/120 Batteries OK #3 impedance low. Battery replaced. OK UPS-1 2010-12 120 New Batteries All batteries replaced OK UPS-1 2011-07-19 120/120 Batteries OK None OK UPS-1 2014-04-08 120/120 Batteries OK None OK UPS-1 2014-12-23 120/120 Batteries OK None OK UPS-2 2009-11 36 New Batteries All batteries replaced OK UPS-2 2013-11-22 36/36 Batteries OK None OK UPS-2 2014-04-08 36/36 Batteries OK None OK UPS-2 2014-12-23 36/36 Batteries OK None OK

SUMMARY

UPS-i, For a period of 5 1/2 years, 1 battery failure UPS-1, For a period of 4 years, 0 battery failures UPS-2, For a period of 5 years, 0 battery failures