Line Connection Variants; Ways Of Connecting The Line Supply - Siemens SINAMICS S120 Manual

3.11

Line connection variants

3.11.1

Ways of connecting the line supply

Note
Permissible line supplies
In combination with the drive system, the motors are generally approved for operation on TN
and TT line systems with grounded neutral point and on IT line systems.
A distinction is made between the following line connection versions:
● Line connection components to be directly connected to the line supply
● Operating line connection components via an autotransformer
● Operating line connection components via an isolating transformer
Danger to life due to electric shock if isolating transformer is omitted
To maintain safe electrical separation, for high voltages, an isolating transformer must be
used.
• Install an isolating transformer for voltages > 480 V +10%.
Fire hazard for the motor due to overload of the insulation
There is higher stress on the motor insulation as a result of a ground fault in an IT line
system or a line system with grounded line conductor.
TT line supply systems generally have a grounded line conductor.
A possible result is the failure of the insulation with a risk for personnel as a result of smoke
and fire.
• For IT line supplies, use a monitoring device that signals an insulation fault.
• Correct the fault as quickly as possible in IT systems so the motor insulation is not
• For line supplies with grounded line conductor, use an isolating transformer with
Booksize Power Units
Manual, (GH2), 07/2016, 6SL3097-4AC00-0BP8
DANGER
WARNING
overloaded.
grounded neutral point (on the secondary) between the line supply and the drive
system.
Line connection and line-side power components
3.11 Line connection variants
137