Bypass With Synchronization, Without Overlap (P1260 = 2) - Siemens SINAMICS S120 Function Manual

● After the motor has been synchronized to the line frequency, line voltage and line phase,
● The bypass mechanism evaluates this signal and closes contactor K2 (r1261.1 = 1). The
● After contactor K2 has signaled back the "closed" state (r1269[1] = 1), contactor K1 is
● If the on command is withdrawn in this phase, the drive converter changes into the basic
Retrieving the motor from supply mode functions the same but in reverse:
At the start of the process, contactor K2 is closed and contactor K1 is opened.
● The "Command bypass" control bit is canceled (e.g. by the higher-level automation).
● The bypass function sets the control word bit "synchronizing".
● Pulses are enabled. Since "Synchronize" is set before "Pulse enable", the converter
● After the motor has been synchronized to the line frequency, line voltage and line phase,
● The bypass mechanism evaluates this signal and closes contactor K1. The signal is
● Once contactor K1 has reported "closed" status, contactor K2 is opened and the motor is
4.22.2

Bypass with synchronization, without overlap (p1260 = 2)

Description
When "bypass with synchronization without overlap (p1260 = 2)" is activated, contactor K2 to
be closed is only closed when contactor K1 has opened (anticipatory type synchronization).
Phasing of the motor voltage before synchronization must be set such that there is an "initial
jump" upstream of the supply to which synchronization should be carried out. This is done by
setting the synchronization setpoint (p3809). As a result of the motor braking in the short
time during which, both contactors are open, when closing contactor K2, a phase and
frequency difference of approximately zero is obtained.
Sufficiently large moment of inertia is a precondition for sound functioning.
It is no longer necessary to use the de-coupling reactor after having determined the
synchronizing setpoint (p3809).
Drive functions
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
the synchronizing algorithm reports this status (r3819.2).
signal is internally evaluated - BICO wiring is not required.
opened and the drive converter inhibits the pulses. The drive converter is in the "hot
standby" state.
standby state. If the appropriate contactors are being used, the drive converter is isolated
from the line supply and the DC link is discharged.
interprets this as a command to retrieve a motor from the supply and to take it over.
the synchronizing algorithm reports this status.
internally evaluated - BICO wiring is not required.
operated again on the converter.
Vector control
4.22 Bypass
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