Key selection criteria include:
- Load requirements: Measure actual power draw in watts (not just VA), consider power factor (0.95-1.0 for modern IT), and plan for growth.
- Runtime needs: Match to business continuity requirements rather than rules of thumb.
- Topology: Online double-conversion is standard for mission-critical IT.
- Battery chemistry: Compare VRLA vs Li-ion based on TCO, not just upfront cost.
- Efficiency: Consider heat dissipation (150-300W for typical rack UPS) and cooling costs.
- Physical constraints: Check rack space (typically 2-6U for UPS plus batteries), weight limits.
- Compliance: Verify UL 1778 (UPS safety), UL 1973 (batteries), and other relevant standards.
Always validate with actual measurements from intelligent PDUs or server telemetry before finalizing selection.
This answer is sourced from Posts《Server rack battery backup system》