WHAT CAN GO WRONG WITH A

UPS CAPACITY TESTJohn Polenz

Emerson Network Power Liebert Services

WHAT CAN GO WRONG WITH A UPS CAPACITY TEST?

Prior to the test During the test After the test

WHAT CAN GO WRONG PRIOR TO THE TEST?

WHAT AND HOW WILL THE TEST BE CONDUCTED?

Just kill the input and let’er run till she drops and see how long it runs!

HOW WILL THE TEST BE PERFORMED?

Do you use IEEE 1188, 450, &1106 as a reference and guide?

Do you know what the Battery Manufacturer requirements are?

BATTERY PRE-TEST REQUIREMENTS UNKNOWN! Most require initial/equalize charge –

Really? 72 hour float after equalize and prior to

testingCool down?Dissipation of Gas build up on plates

Initial/equalize Timelines for VLA can be extensive150 hrs vs 24 hrs

Ensuring Full state of ChargeConstruction events

Constant current testing vs constant power

WHAT TYPE OF TEST ARE YOU CONDUCTING System functionality vs Battery capacity More than not with UPS applications

Primarily acceptance testing No planning or knowledge of battery

manufacturers requirements for capacity testing IOM not reviewedTimeline issues

DO YOU KNOW WHAT TO TEST TO? Test requirements

What is the actual sizing of the battery?

You mean I have to know the sizing for the battery?

WHAT IS TAKEN INTO ACCOUNT FOR UPS BATTERY SIZING KVA/KW load Inverter efficiencies Power factor Aging factor Temperature Number of cells/string Put the info into the formulas-KVA Rating X Power Factor = KW Load KW Load ÷ Inverter Efficiency = KW Battery LoadKW Battery Load ÷ # of Cells = W/Cell requirement

This is the “WHY” you want to test as a system!

LACK OF BATTERY PREP FOR THE TEST What prepping?

The battery has been on float for a couple of days

You discover that the battery has been discharged multiple times due to SAT requirements

UPS voltage setting not verified prior to the test

UPS End Cell Voltage not verified or known Voltage drop in system

Battery and UPS to battery connections

LACK OF BATTERY PREP PRIOR TO THE TEST Temperature is not considered as an

issue Not prepped as required by the

manufacturer Not enough time in schedule Didn’t have the information Didn’t realize the requirements existed Assumed just a 15 minute battery

WHAT CAN GO WRONG DURING THE TEST? No data recording

Data logging equipment issues Inadequate data collected

System data only at the UPS At the beginning and at the end of the test

IR testing -Thermal concerns –when do we stop the test? Connection concerns

High resistance –high temperatures Battery temperature

No parameters established Cell reversal Equipment malfunctions

WHAT CAN GO WRONG AFTER THE TEST?

FAILED TESTS – ARE THEY REALLY? It didn’t make the time!

The system only ran for 6.5 minutes instead of 8 minutes

Battery temperature was found to be 62F Not all the units met the ECV requirement!

System vs. individual cell/unit ECV Some units fell below specified ECV Test ran for 15 minutes, but battery was sized

for 10 minutes? Not tested at 77F(25C)

Temperature was at 62F Didn’t ensure battery was at FSOC

FAILED TESTS – ARE THEY REALLY? Didn’t perform initial charge Didn’t perform initial charge properly Didn’t provide 72hr float prior to testing No monitoring for the test – only system

level monitoringNo data to prove or disprove

FAILED TESTS – ARE THEY REALLY? Metering not calibrated Only using UPS meters to collect system

data

Time not monitored during the test Not every cell/unit met the ECV cutoff –

1.60-1.67 v/c

PERCEIVED FAILED TESTS Didn’t make time! No final data review No calculations to verify test results

Are not familiar with IEEE rate adjusted or time adjusted calculations

No one knows actual sizing of the battery

Test stopped before it should beWrong ECVWrong time

No agreement on “stop test” criteria

WHAT CAN GO WRONG Lack of prior planning

When to stop the test is not known Improper equipment used

Wrong size (voltage)load bankCan cause a fire

Issues with equipmentOut of calibrationDoesn't measure properlyDoesn’t record good data to be reviewedDoesn’t record the data at all

WHAT CAN GO WRONG Test Equipment failures Facility damage Misinterpretation of battery capacity Delays in commissioning Additional costs incurred

Expect tests to be run until the battery makes the numbers!

Customer dissatisfaction Battery failed

MORAL TO THE STORY Make no Judgment calls prior to data analysis

Alarms customer! Plan the testing

Agreement on: Testing parameters Testing procedures Capacity calculations/analysis process Timelines

Know the battery parametersSizingTemperature impactECV

MORAL TO THE STORY Collect proper data

System levelCell/unit levelThe more the better!

Analyze the data collected IEEE 1188, 450, 1106Rate adjusted method

Consult the battery manufacturer’s if there are questions/concerns

THANK YOU FOR YOUR ATTENTION!