Protecting The Motor Against Thermal Overload; Implementing A Bypass Connection - INVT Goodrive 300 Operation Manual

inverters
Goodrive300
the short-circuit current.

4.4.3 Protecting the motor against thermal overload

According to regulations, the motor must be protected against thermal overload and the
current must be switched off when overload is detected. The inverter includes a motor
thermal protection function that protects the motor and closes the output to switch off the
current when necessary.

4.4.4 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 inverter if faults occur in some significant
situations.
In some special situations, for example, if it is only used in soft start, the inverter can be
conversed into power frequency running after starting and some corresponding bypass
should be added.
 Never connect the supply power to the inverter output terminals U, V
and W. Power line voltage applied to the output can result in permanent
damage to the inverter.
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 inverter output
terminals simultaneously.
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Installation guidelines