Protect The Motor And Motor Cables; Implementing A Bypass Connection - INVT Goodrive20-EU Series Operation Manual

Goodrive20-EU Series VFD
Note: Select the fuse as the manual indicated. The fuse will protect the input power cable from
damage in short-circuit situations. It will protect the surrounding devices when the internal of
the VFD is short circuited.

3.4.2 Protect the motor and motor cables

The VFD protects the motor and motor cable in a short-circuit situation when the motor cable
is dimensioned according to the rated current of the VFD. No additional protection devices are
needed.
 If the VFD is connected to multiple motors, a separate thermal overload

3.4.3 Implementing a bypass connection

It is necessary to set power frequency and variable frequency conversion circuits for the
assurance of continuous normal work of the VFD if faults occur in some significant situations.
In some special situations, for example, if it is only used in soft start, the VFD can be
converted into power frequency running after starting and some corresponding bypass should
be added.
 Never connect the supply power to the VFD output terminals U, V and W.
If frequent shifting is required, employ mechanically connected switches or contactors to
ensure that the motor terminals are not connected to the AC power line and VFD output
terminals simultaneously.
Input cable(three phase)
Figure 3-17 Fuse configuration
switch or a circuit breaker must be used for protecting each cable and
motor. These devices may require a separate fuse to cut off the
short-circuit current.
Power line voltage applied to the output can result in permanent damage
to the VFD.
VFD
Fuse
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Installation guidelines
M
3~