FOTEK GD20-004G-2, Руководство по эксплуатации

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Goodrive20 Series VFD Installation guidelines
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3.3 Wiring protection
3.3.1 Protect the VFD and input power cable when a short circuit occurs
Protect the VFD and input power cable in short circuit situations and against thermal overload.
Arrange the protection according to the following guidelines.
VFD
Fuse
Input cable(three phase)
Figure 3-15 Fuse configuration
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.
3.3.2 Protect the motor and motor cables
If the motor cable is selected based on the rated current of the VFD, the VFD can protect the
motor cable and motor when a short circuit occurs. The VFD provides the motor thermal
overload protection function, which can protect the motor, and lock the output and cut off the
current when necessary.

If the VFD is connected to multiple motors, a separate thermal overload
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.
3.3.3 Establish 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.
Power line voltage applied to the output can result in permanent damage
to the VFD.
If frequent shifting is required, employ mechanically connected switches or contactors to
ensure that the motor terminals are not simultaneously connected to the input power cable
and the output terminal of the VFD.