Instrument transformers for 50 Hz, U<(Index)m> 0.72 kV to 52 kV - Part 9: Voltage Transformers U<(Index)m> = 12 kV and U<(Index)m> = 24 kV - Narrow design, main dimensions, indoor type
Deutsches Institut Fur Normung E.V. (German National Standard) , 10/01/2013
