Product Description Our HF series have following design advantages: -High Output Capacity - Up to 12000W -Ultra Low THD (Typically 7%) very high overload capacity - Under full linear load ZODORE HF inverters are designed low THD of 7% in contrast to other models with range 15- 20% s. This means that only 7% of the power is not available at the fundamental frequency. -Handles three x 3 times the surge power Surge is 3x rated load power for 20sec minimum. -Three Step intelligent battery charging: Multi stage charging algorithm for optimal battery charging. -Powerful Charge Rate - up to 120Amp Selectable from 0-100% -Auto Gen Start Function For Off Grid System with generator as back up power. Automatically starts generator when the battery voltage reaches low levels. Increases lifetime of battery. - MPPT Solar Charger Controller option available -Adjustable dual frequencies 50/60hz -Our transformer based inverter has a circuit breaker on the DC and AC side for protection. This provides short circuit protection under all conditions. -High Quality transformer: 180deg class insulation (high temperature design). Quality magnetic core -Isolation: Isolation between the input DC side of the inverter & the output AC side of the inverter is achieved via the transformer -Intelligent Load Sensing Fan: As the load increases the speed of the fan increases. This allows for quieter operation and longevity of the fan.