11KV Low & High Voltage Electrical Composite Polymer Dropout Fuse Factory Product Description Condition of Use: 1. The ambient air temperatures within the range of -30 degreeto +40 degree; 2. The altitude above sea level not exceeding 1, 000m; (If the altitude is higher than 1, 000, it needs adjust. ) 3. Frequency of the A. C. Power supply not less than 48Hz and not exceeding 52Hz; 4. Earthquake intensity not exceeding 7 degrees; 5. Maximum wind speed not exceeding 35m/s. Technical Standard: The technical performance of the products is in confirmed to IEC291, 282.