Extended Functions
Bypass (vector)
4.25.2
Bypass with synchronization, without overlap (p1260 = 2)
When "bypass with synchronization without overlap (p1260 = 2)" is activated, con-
tactor K2 to be closed is first closed when contactor K1 has opened (anticipatory
type synchronization). The motor voltage phase position before synchronization
must be set so that a "lead" is obtained before the line supply to which the system
must be synchronized; this is realized by setting the synchronizing setpoint
(p3809). As a result of the motor braking in the short time during which, both con-
tactors are open, when closing contactor K2, a phase and frequency difference of
approximately zero is obtained.
It is no longer necessary to use the de-coupling reactor after having determined
the synchronizing setpoint (p3809).
Network
Fig. 4-32
Activation
It is only possible to activate the bypass function with synchronization without over-
lap (p1260 = 2) using a control signal (p1267.0 = 1, p1267.1 = 0, p1267.2 = 0); it is
not possible to activate this function using a speed threshold or a fault.
4-282
Converter
K1
M
~
Circuit example, bypass with synchronization without overlap
K2
Interlocked against
simultaneously closing
© Siemens AG 2006 All Rights Reserved
SINAMICS S120 Function Manual, 03/2006 Edition
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