UPS Batteries

Module from the Electrical Engineering Curriculum curriculum.

Module 9 - UPS and Station Batteries · Learning Objectives · 1. Size UPS per IEEE 446 for critical loads (duration and VA) · 2. Select VRLA (AGM/Gel) vs flooded lead-acid per IEEE 485 / 1188 · 3. Apply 8 hr to 72 hr autonomy for plant control and safety systems · 4. Design DC system 125V or 250V per IEEE 946 for switchgear · 5. Verify rectifier/charger sizing for equalize charge · UPS Architecture Comparison

Topology	Efficiency	Transfer Time	Cost	Use	Note
Offline standby	95-98%	4-8 ms	Lowest	Small loads	Not for sensitive
Line interactive	95-97%	2-4 ms	Low	Minor IT loads	Basic
Double-conversion online	92-95%	0 ms	Highest	Critical IT, DCS	Most refineries
Delta-conversion	96-97%	0 ms	High	Large critical loads	Higher eff
Rotary/flywheel	95%	0 ms	Very high	Data centers	Short ride-through

Source: Electrical_Engineering_Curriculum_v1.xlsx · Sheet: UPS Batteries

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