Siemens SINAMICS G150, Operating Instructions Manual

Page: 553 / 680

Functions, monitoring, and protective functions
9.3 Extended functions
Converter cabinet units
Operating Instructions, 07/2016, A5E03347396A
553
NOTICE
Device damage due to phase shift in the bypass circuit
Changing the phase sequence or the direction of rotation using p1820/p1821, without
physically adapting the phase cables results in incorrect synchronization, which can result
in mechanical damage to the plant.
•
Ensure that no different phase sequence occurs in the bypass circuit between line
operation and converter operation.
•
If you change the direction of rotation via p1820/p1821, adapt the phase lines
accordingly.
Precondition
The bypass function is only possible for encoderless closed-loop speed control (p1300 = 20)
or V/f control (p1300 = 0...19) and when an induction motor is used.
Establishing the bypass function
The bypass function is part of the "technology controller" function module that can be
activated by running the commissioning Wizard. Parameter r0108.16 indicates whether the
function module has been activated.
9.3.2.1 Bypass with synchronizer with degree of overlapping (p1260 = 1)
Description
The "Bypass with synchronization with degree of overlapping" is used for drives with a low
moment of inertia. These are drives for which their speed would sink very fast when the K1
contactor opens.
When "bypass with synchronization with overlap (p1260 = 1)" is activated, the motor is
transferred, synchronized to the line supply and is also retrieved again. During the
changeover, both contactors K1 and K2 are closed at the same time for a period (phase lock
synchronization).
This bypass type requires a VSM10 Voltage Sensing Module that measures the line voltage
for the drive to be synchronized.
An output reactor is used to de-couple the drive from the line supply - the impedance value
for the reactor is 10 (±2) %.