Voltage Levels – IEC 61000-3-6

As far as I know, IEC has not mentioned medium voltage in any of its standards except in IEC 61000-3-6.

The following table provides the different voltage levels as per IEC 61000-3-6.

IEC Voltage Levels[1]
Voltage Level Range (line-to-line)
LV (Low voltage) Un ≤ 1kV
MV (Medium voltage) 1kV < Un ≤ 35kV
HV (High voltage) 35kV < Un ≤ 230kV
EHV (Extra high voltage) Un > 230kV

NOTE The boundaries between the various voltage levels may be different for different countries

It is good to note that [1] is the only IEC standard that mentions about Medium voltage. All other IEC standards consider voltages above 1kV to be high voltage.

References:

  1. IEC/TR 61000-3-6
    Electromagnetic compatibility (EMC) – Part 3-6: Limits – Assessment of emission limits for the connection of distorting installations to MV, HV and EHV power systems