VFD With By Pass FASD Starter

The above panel illustrates a typical VFD panel with by pass arrangement. VFD starters are bought out for which by pass arrangement with auto isolation of the VFD is done.

VFD’s are bought out and connected to series reactors on both incoming and outgoing side or on the out going side (as needed by customer) are connected through incomer and outgoing contactor to the system and motor respectively. The major problem in this case is arrangement of a by – pass system. In the bypass system say an FASD by pass, in addition to the input and output contactors of the VFD, a full 3 contactor FASD with timer and overload tripping facilities are provided. Please note that the delta contactor in this system will be used both for VFD and by pass starter.
Please note that all the input, output and by pass are fully rated contactors suited or the capacity of motor. Suitable circuit adoptions are done to achieve results.

The soft starter by pass is also very similar to the VFD by pass. However choices of reactors are left the customers.
The VFD it self uses the fact that the induction motor is frequency dependent and the voltages depend on frequency hence any other switch is media not needed for the VFD itself.