Inspection and test data analysis John Polenz Supervisor Battery Technical Support - Vertiv 06/11/2017

Data collection Why collect the data if you aren’t going to do anything with it - Except file it!

discussion Preventive Maintenance Inspection Data Consistent readings taken and recorded Baselines established Analysis of the data Single report data analysis Capacity Testing Data Analysis Data recording Unit and system data recording Final analysis

Data analysis So many times with battery analysis – IT DEPENDS! ASK Questions to help get the answers: Was the battery recently cycled? How long has the value been that way? Is it recovering or getting worse? Has anything changed that could impact the battery? Have any corrective measures been attempted? Have you verified system readings at the battery – not at the charger? *Additional Notes

Collecting Consistent readings! Getting the right readings! PM Inspection DATA Collecting Consistent readings! Getting the right readings! Importance of test equipment lead placement consistency Different technicians will place test leads differently Can negatively impact readings Can impact trending Misleading on actions to take *Additional Notes

Establish ohmic Baselines Trending is best method *Additional Notes

Establish baselines Establish Proper Baselines - Thresholds Voltage Internal Ohmic Temperature Ambient/unit System Float Unit float Specific gravity *Additional Notes

Proper baselines Example: 7500 = 11250 (50% above first reading) 3750 = 5625 (50% above 6 months reading) Incorrect baselines can mask potential concerns! *Additional Notes

Specific gravity data analysis Can be hard to make correct determination *Additional Notes

Temperature swings *Additional Notes

Validation of data Float = 2.179 v/c Actual battery float requirement *Additional Notes

Investigation for: Unit Float issues Internal Resistance increase Validation of data Investigation for: Unit Float issues Internal Resistance increase Actual float should be 535 VDC Nom. Float – 2.23 v/c Recorded – 2.246 v/c At the battery – 2.245 Exceeds manufacturer recommendations *Additional Notes

Take the Readings and move on Sometimes it is plain Sight! *Additional Notes

Don’t only record the data Low voltages Lower temperatures Low float setting *Additional Notes

Alarm triggers *Additional Notes

Single data set analysis Improper threshold It did not identify Suspect units! Quick visual look! The 3 units all exceed 50% above baseline using present data set *Additional Notes

Single data set analysis *Additional Notes

Contributing factors can be identified with analysis Voltage drop Over charge Under charge *Additional Notes

Lack of data for evaluation *Additional Notes

Capacity test Analysis Capturing useable data Capturing only system level vs. unit level Voltage, temperature, current, time Where the data is collected is important UPS application – at the battery and at the UPS to aid in system design verification, *Additional Notes

Don’t assume the battery has failed - Didn’t make time Data analysis Don’t assume the battery has failed - Didn’t make time Didn’t meet the ECV requirement Cell/unit dropped out early Example: The following discharge testing results were observed:  On an 11 minute backup time rating, the batteries ran for approximately 16.5 minutes. The batteries supplied over 100% capacity using the industry standard IEEE 1188, rate adjusted calculations. At the 15 minute discharge point (before voltage drop-off) the lowest battery voltage was 9.871 The test ran until the end cell voltage reached 1.60 volts/cell and the batteries supported an average load of 55.66kw for 16.5 minutes. *Additional Notes

Verifying report alarm thresholds Default software setting to 1.67v/c Changed to 1.50 v/c *Additional Notes

Data logging helps to make analysis easier and quicker Test data Data logging helps to make analysis easier and quicker *Additional Notes

Uniform test results *Additional Notes

Do not make battery performance assumptions till the data is analyzed Analyze the data collected Verify the load applied to UPS/battery Verify published performance specification for the battery Verify ECV cutoff setting Verify temperature of the battery during the test Calculate the battery capacity per IEEE 1188 *Additional Notes

Summary Some data is better than none The more data the better for evaluation More data provides better trending Better trending leads to better prevention to failures Baselines need to be established properly Data analysis can help to identify: Charger issues Environmental concerns Failing battery Voltage drop identification Improper maintenance practice *Additional Notes

Thank you for your attention!