1.Over 97.6% efficiency; 2.MPPT efficiency up to 99.99%; 3.Built-in a high-accuracy clock:records real-time info ... terminalCertificationsTÜV CE VDE 0126-1-1(VDE-AR-N4105),ENEL,G59 AS4777(AS3100),EN61000-6-1:4,EN61000-3-2:3,EN61000-11:12Maintenance5 years ... ,(10 years Optional) . Grid-tied Solar Inverter(1.5KW,2.2KW,3KW)