Siemens SIMOVERT MASTERDRIVES Motion Control Instructions De Service page 214

Connecting-up
NOTE
7-2
The converters are suitable for connecting to networks with an earthed
star point (TN networks and TT networks according to EN 60364-3).
For connection to networks with a star point that is not earthed (IT
networks) or networks with an earthed outer conductor, converters with
option L20 are necessary.
The converters are designed for overvoltage category III in accordance
with IEC 60664-1. In networks with an earthed outer conductor and a
line voltage of > 600 V AC, the equipment must be modified in order to
limit any occurring overvoltages to overvoltage category III in
accordance with IEC 60664-1.
6SE7087-7JK50
Operating Instructions SIMOVERT MASTERDRIVES
08.2008
Siemens AG