For indoor application ,when the Rated voltage is below 660V, AC frequency is 50Hz,meansure energy,current and protect relay Specification1.Rated Voltage: 660V2. Rated Frequency : 60HZ3. Rated Primary Current : 5-1500A4. Rated Secondary Current : 5A:Rated Primary Current (A) Rated Burden (VA) 0.5S 0.2 0.2S 0.5 5-600 5 5 5 10750-1500 10 10 10 10 LQG-0.66 series current transformer