12kV Power Transformer,50Hz Power Transformer,ONAN Power Transformer 1)30~31500kVA 2)IEC/ISO 3)Copper wind 4)1year warranty 12kV Power Transformer, 50Hz Power Transformer, ONAN Power TransformerStandardsGB1094.1~2-1996GB1094.3,.5-2003GB/T6451-1999Service conditions 1) Altitude: ≤1, 000m 2) Maximal ambient temperature: +40.C3) Maximal daily average temperature: +30.C4) Maximal annual average ...