Siemens Sinamics S120 Manual page 54

Line-side power components
3.3 Active Interface Modules, air-cooled
Figure 3-6 Connection example Active Interface Module, frame size HI
NOTICE
Damage to the device through different phase sequence in the pre-charging and main
circuits
Different phase sequences in the pre-charging and main circuits can overload and destroy
the pre-charging resistors of the Active Interface Module during the brief overlap period,
where both contactors are simultaneously closed.
• Close the power cables in the pre-charging and main circuits with the same phase
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sequence.
Liquid-cooled chassis power units
Manual, (GH7), 11/2016, 6SL3097-4AM00-0BP7