Application Guide

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Miscellaneous
Control Power Terminals
The VFD will generally have an on board power supply for use with external equipment e.g. transmitters. A simple voltage
check of this power supply together with an other terminals that output voltages will give a good indication of the state of the
control board.
Use of Multiple Auto Resets
Most VFDs have a function which provides auto reset in the event of a trip. This function is designed to enhance the reliability
of the VFD service provided.
IMPORTANT
Use the auto reset function with caution.
Example: When an over current trip occurs, the over current condition causes abnormal heating within the input bridge rectifier
and output power transistors. If the over current condition occurs repeatedly within a short space of time and the VFD is
programmed to reset itself automatically. The reset can be programmed with insufficient time between resets to allow for
cooling. This results in the power devices becoming thermally stressed, shortening their life expectancy.