Battery & UPS Sizing Quick Reference Card
Free download · 85 × 54mm (credit card size)
UPS and battery sizing calculations come up on every critical power project. This pocket card gives you the formulas and limits without pulling up a textbook. The front covers battery capacity (Ah) = (P × t) / (V × η × DoD), autonomy time calculation, temperature correction (~1%/°C below 25°C), and the IEEE 485 section-by-section discharge method overview. The reverse provides DoD limits for common battery types (VRLA 80%, lithium-ion 90%, flooded lead-acid 75%), float vs equalise charge voltages for VRLA (2.27V/cell vs 2.45V/cell), and charger sizing rule Ich ≥ C10/10. QR links to ECalPro UPS sizing resources.
What's Included
How to Print
- ●Recommended paper: 250–300gsm cardstock
- ●Print double-sided, flip on short edge
- ●Cut along crop marks with a paper trimmer
- ●Laminate with 80–125 micron pouches for durability
- ●Fits in wallet, toolbox, or pocket
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Frequently Asked Questions
What paper should I print this on?
Print on 250–300gsm cardstock for durability. Use duplex (double-sided) printing and cut along the crop marks. Laminate with 80–125 micron pouches for long-term site use.
Can I distribute this to my team?
Yes. All ECalPro reference cards are free to download, print, and distribute within your organization. Keep the ECalPro branding and QR code intact.
What standard does this reference?
This card references IEEE 1188 (VRLA battery maintenance), IEC 60896-21 (stationary lead-acid batteries), and IEEE 485 (lead-acid battery sizing for stations).
How often is this updated?
Updated when battery or UPS standards are revised. Battery chemistry fundamentals are stable.