Step 1: Inspect the battery string
Check battery appearance, terminals, inter-cell connectors, cabinet condition and signs of overheating, swelling, leakage or corrosion.
Battery Testing Guide
How to test UPS batteries before failure happens.
UPS batteries should be tested regularly to identify weak cells, abnormal voltage, rising internal resistance and battery strings that may not support the required backup runtime.
Why UPS battery testing matters
UPS systems depend on standby batteries during power failures. A battery string can appear normal during daily operation, but one weak cell may reduce the available backup time when the system is actually needed.
Step 2: Measure voltage
Record each cell or block voltage. Abnormal voltage differences can indicate charging imbalance, aging or possible battery failure.
Step 3: Test internal resistance
Internal resistance testing helps compare batteries in the same string and identify cells that are aging faster than others.
Recommended tool
For UPS battery maintenance, PITE3915 can measure battery voltage and internal resistance, store test data and export reports through DataView software.
PITE3915 Battery Tester
Supports 1.2V, 2V, 6V and 12V standby batteries with a 5–6000 Ah capacity range.
View product →Data reports
Transfer test data by USB, organize results by site and battery string, and export Excel reports.
View downloads →Need model advice?
Send us your UPS battery voltage, capacity, battery type and testing requirement.
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