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SANTERNO
USER MANUAL
Fig.3-26 Auto switch Cabinet
Fig.3-27 Manual Switch Cabinet
Fig.3-24 Manual Bypass Cabinet
Fig. 3-25 Auto Bypass Cabinet (with isolation)
MV VFD
MV VFD
MV VFD
MV VFD
MV VFD
MV VFD
MV VFD
MV VFD
entered from the bottom of bypass cabinet. Cord cables are adopted to connect the bypass cabinet and the VFD,
and laid inside the cabinet.
When a short time stop is permitted, a manual bypass cabinet can be used, and switched by operator, see Figure
3-24. There are three knife switches inside the manual bypass cabinet: QS21 and QS22 are together as one
double pole double throw switch, which can ensure the grid power not connecting to the VFD output terminal.
There are two types of switch cabinet: manual switch cabinet transfer and auto switch cabinet. The function of
switch cabinet is that the VFD supplier power for two motors separately, to improve the utilization rate of VFD.
This scheme can be used under two conditions: the motors are one for spare one for use; two motors work under
similar condition.
Switch QS1 and QS2 in manual switch cabinet are mechanical interlocked. 1QF and QS1, 2QF and QS2 are
electrically interlocked, see Figure 3-27. Switch QS1 and QS2 in auto-switch cabinet are not mechanically
interlocked. KM1 and KM2, KM1 and 1QF, KM2 and 2QF are electrically interlocked, as Figure 3-26.
