Battery Monitoring Fundamentals & Experience

Battery Monitoring Introduction BTECH developed the first stationary battery monitor based on trend analysis in 1991, based on research begun in the 1980s Leading Indicator: Impedance Rise Technology has proven itself in the past 15 years First challenge met: proving the method of continuous battery monitoring Action Plan: Weak cells are identified and replaced before battery system performance is affected

Market Experience Customers That Embraced Battery Monitoring Have: Virtually eliminated their battery failure risk Ensured performance of their critical power systems Reduced battery maintenance costs Remote Monitoring Of Hundreds Of Battery Systems Has Demonstrated: Many previously undocumented battery conditions Proof that a need for change is required in the way critical battery systems are managed The End-user Base Is Largely Unaware That A Proven Solution For Their Battery Problems Exists

Why Critical System Batteries Should Be Monitored Mission Critical Systems Require The Benefits Of On-line Battery Monitoring Systems Best possible reliability and practices demanded Systems cannot always be taken of-line for maintenance Extensive annual or periodic tests are expensive and interrupt business operations Budget constraints often limit or eliminate battery maintenance Personnel changes

Why Critical System Batteries Should Be Monitored Up To 85% Of All UPS Failures Are Battery Related UPS Monitoring Systems can’t detect failures proactively Failures occur between service intervals Inconsistent and often compromised maintenance Lack of customer awareness and/or expertise Battery Failure Can Happen In 2 Weeks Failure can occur at any time in the battery life cycle Successful discharges or discharge tests can speed failure A quarterly check cannot assure the battery system will perform

Why Critical System Batteries Should Be Monitored 5+% Of New Batteries Fail Within The Warranty Period Significant impact to critical system reliability Installing new batteries does not reduce risk of failure Users need a method to find the bad ones in time A warranty is not the same as a performance guarantee Changes Happening In The Battery Industry China as main supplier of lead and batteries Many new battery types have entered the market with little or no track record Manufacturers are under pressure to reduce cost The quality of batteries in the market has suffered

Improve the Way Batteries are Managed Move From Battery Maintenance to 24x7 Battery Management Battery Maintenance Battery checking and assurance occurs only 4 days of the year -- as quarterly battery service is performed Battery Management Battery assurance occurs 24 X 7

Example Battery Failures Found At Customer Sites

Float Voltages vs. Unit Number Example #1 - 2 Strings of 40-12V VRLAs Float Voltages vs. Unit Number Float Voltages Show System Is OK

Impedance vs. Unit Number Example #1 - 2 Strings of 40-12V VRLAs Impedance vs. Unit Number Green: Initial Read (Baseline) Red: Maintenance Limit (+20%) Purple: Critical Limit (+30) The Unit Impedances Show Another Story

Each Yellow Point = One Week Example #2 – Unit #6 Voltage vs. Time: Voltage Looks OK Each Yellow Point = One Week

Impedance vs. Time: Impedance Rises 120% Example #2 – Unit #6 Impedance vs. Time: Impedance Rises 120% Green: Initial Read (Baseline) Red: Maintenance Limit (+20%) Purple: Critical Limit (+30)

Voltage vs. Time: Voltage Drops 10% Example #3 - Unit 13 Voltage vs. Time: Voltage Drops 10% Unit 50 Impedance: 5.06 Milli-ohms (180.07% of String Initial Measurement) [2.81 Milli-ohms]

Impedance vs. Time: 120% in Two Weeks Example #3 - Unit 13 Impedance vs. Time: 120% in Two Weeks Failure Within 2 Weeks

Voltage vs. Time: 10% Voltage Drop within 2 Weeks Example #4 – Wet Cell Unit 213 Voltage vs. Time: 10% Voltage Drop within 2 Weeks

Impedance vs. Time: No Change Recorded Example #4 - Wet Cell Unit 213 Impedance vs. Time: No Change Recorded Customer Replaced the Unit

Impedance vs. Time: Effects of Re-Torquing Example #5 - Unit 67 Impedance vs. Time: Effects of Re-Torquing Battery Finally Replaced Service Provider Retorques Customer Notified

Voltage vs. Time: Note That Voltages Have Barely Changed Example #5 - Unit 67 Voltage vs. Time: Note That Voltages Have Barely Changed

Voltage vs. Time: Detecting Thermal Runaway Example #6 - Unit 42 Voltage vs. Time: Detecting Thermal Runaway

Temperature vs. Time: Detecting Thermal Runaway Example #6 - Unit 42 Temperature vs. Time: Detecting Thermal Runaway Temperature Sensor Mounted in Cabinet

System Voltage vs. Time: No Changes Example #6 - Unit 42 System Voltage vs. Time: No Changes

Impedance vs. Unit Number Example #7 - Unit Impedances Impedance vs. Unit Number Notice the 5 Units With High Impedance

Voltage vs. Unit Number During Discharge Example #7 - Unit Voltages Voltage vs. Unit Number During Discharge These 5 Units Have the Lowest Voltage After Discharge

Benefits of Battery Monitoring Critical system battery performance is assured Detection of major battery problems with enough time to respond Reliability of backup power is increased Risk and revenue lost due to downtime are virtually eliminated Battery management and maintenance costs can be reduced significantly Customer experience: Battery service life can be increased up to 100% when weak cells are replaced in time Reduction of manual maintenance

BTECH’s Fifth Generation Battery Monitoring System The Product BTECH’s Fifth Generation Battery Monitoring System

Modular System Components Control Module Voltage Module Current Module Real Time Monitoring • Cell Impedance • Ambient & Pilot Temperature • String & System Current (Float/Charge/Discharge) • Cell & System Voltage (Float/Discharge)

Unmanned Communications: 48V VRLA Stack S5 VRLA Stack Installation Unmanned Communications: 48V VRLA Stack

3-Phase UPS: 40-12v (480V) VRLAs S5 VRLA Cabinet Installation 3-Phase UPS: 40-12v (480V) VRLAs

S5 Functions Measurement of key battery performance parameters for trend analysis (failure prediction & prevention) Unit Impedance - Impedance is the leading indicator of battery failure and finds bad batteries Plate cracking, warping, corrosion, post & strap corrosion and cell dry-out are easily detectible Interconnect problems Initial measurements for each unit used for baselines Unit Voltage – Can also be a leading indicator of failure Dendritic shorts Thermal runaway Ambient & Pilot Cell Temperatures – Problem prevention Environmental conditions (placement of battery cabinets)

S5 Functions Measurement of key battery performance parameters in real time for alarm conditions (immediate problems) Unit Voltage System Voltage Float settings and system problems Discharge Events Temperature Thermal runaway detection Air conditioning system problems

Full Data Logging and Analysis: Building the Database S5 Functions Full Data Logging and Analysis: Building the Database Unit Impedance, Voltage and Temperatures Future problems found through data trending and comparisons with initial readings Alarms based on predetermined set points Factory voltage data Initial impedance data Discharge Data Logging of voltages and string currents Eliminates need for data logger during discharge test Full discharge analysis capabilities after any event Warranty Reporting

S5 Communications Building or Facility Management System Integration Modbus over TCP/IP 6 User-configurable dry contact alarms 4 Additional alarm inputs System functions as a “Master” with the ability to initiate communication to outside world Transmitting Information and Alarms Remotely Ethernet (static or dynamic IP) Dial-up modem Retrieving Information in the Battery Room RS232 and USB ports For battery service providers & real time discharge tests

S5 System Software BTECH’s Software Platform Serves as Your Central Monitoring Point for Multiple Systems and Locations BTECH’s BVM Observer collects and distributes data and alarms automatically for up to 1000 systems Runs 24x7 on your network Data can be stored anywhere on your network or PC Provides e-mail and text message alarms BTECH’s BVM Validation Manager provides full data trending, analysis and reporting Simple and easy to use graphing functions On-demand real-time interaction with the BVS

The Leading Indicator of Failure S5 Technology The Leading Indicator of Failure BTECH’s Patented Impedance Method Impedance includes the capacitive effect of the battery and provides a more accurate correlation with battery capacity…the reference measurement method Pulsed DC Impedance at 215 Hz No sinusoidal charging/discharging No effect from AC ripple or downstream noise Multiple measurements made for data averaging and comprehensive noise analysis No Discharge Below Open Circuit Voltage Measurements do not place load on batteries and do not affect battery life

BTECH Impedance Does Not Discharge Your Batteries BTECH’s Impedance Method BTECH Impedance Does Not Discharge Your Batteries

Impedance vs. Resistance (i.e. “Voltage Response”) Comparison With Other Methods Impedance vs. Resistance (i.e. “Voltage Response”) Voltage response results on battery systems on-line are affected by the charger, line noise and battery type Requires repeated deep DC discharges to get results “Fiber Optic” Modular Monitoring Systems Systems are powered by the batteries at all times Measurements remain dormant until called upon by PC based master Weak load signal (1A) provides poor signal to noise ratio Systems Using AC Ripple Or Line Voltage Measurement signal is always changing due to ripple, noise and load, leading to inconsistent results Impossible to separate ripple effects from data

BTECH Impedance vs. Voltage Response Effect of Testing on Batteries BTECH Impedance vs. Voltage Response

S5 System Diagram System Components SCM 600 (Controller) -1 per UPS or Inverter System VM-24 – Up to 24 VSLs and 4 Ts per unit CM-2 – Current Monitor per string (up to 4) CT – Current Transducer (Hall Effect Clamp) VSL – Voltage Sense Lead LCL – Load Control Lead

Additional S5 System Features Complete Isolation from the Battery String System is not powered by your batteries Completely invisible and passive to the battery system, UPS/rectifier and load Factory Designed and Built Wiring Harnesses Ensure system reliability Simple installation in 50% less time Designed to meet site requirements BTECH’s Unique Safety Fuse System Allows easy battery replacement Reduces battery replacement costs by up to 50%

BTECH Corporate Capabilities Complete Turn Key Services: Complete Documentation and Submittals Engineering and Design Installation Services Commissioning, Start-up and Training Field Service and Maintenance Contracts Technical Help Desk Support World Wide Service Network