Bypass - Siemens SINAMICS S120 Function Manual

Description
Redundant operation can be used so that operation can be continued in spite of the failure of
one power unit connected in parallel. In order that the failed power unit can be replaced,
DRIVE-CLiQ cables must be connected in a star-type configuration - it may be necessary to
use a DRIVE-CLiQ HUB Module (DMC20). The failed power unit must be deactivated via
p0125 or via the binector input p0895, before it is removed. When a replacement power unit
has been installed it must be activated accordingly.
Prerequisites
● Parallel connection only works with equivalent (order number) chassis power units.
● Maximum number of parallel power units is 4
● Minimum firmware release 2.4
● Parallel connection of power units with suitable power reserves
● DRIVE-CLiQ star topology (possibly a DMC20, refer to the Equipment Manual)
● Motor with one single-winding system (p7003 = 0)
● No safe standstill
Integration
The boot function with partial topologies is integrated in the system as follows.
● p0125 Activate/de-activate power unit component
● r0126 Power unit component active/inactive
● p0895 BI: Activate/deactivate power unit component
● p7003 Par_circuit winding system
4.20

Bypass

Features
● Available for the vector mode
● Available for induction motors without encoder
Description
The bypass function controls two contactors via digital outputs of the drive converter and
evaluates the feedback signals of the contactors via digital inputs (e.g. via TM31). This circuit
allows the motor to either be fed from the drive converter or connected directly to the supply
line. The drive converter controls the contactors; the feedback signals for the contactor
states must be fed back to the drive converter.
This bypass circuit can be implemented in two ways:
● Without synchronizing the motor to the line supply and
Drive Functions
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4
Vector control
4.20 Bypass
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