UPS/inverter sizing
Load + runtime → UPS rating and battery capacity
Load
Energy600 Вт·год
UPS, VA≥ 600 ВА
12V battery, Ah≥ 118 А·год
VA = W/0.7 (power factor), +30% margin. Battery: Ah = W·h / (12V·0.85 eff·0.5 DoD for AGM). For boilers — pure sine inverter with correct phasing.