Mitsubishi Electric FR-A820-04750-GF Instruction Manual page 107

NOTE
• The internal accumulated heat value of the electronic thermal relay function is reset by inverter power reset and
reset signal input. Avoid unnecessary reset and power-OFF.
• When multiple motors are driven with a single inverter or when a multi-pole motor or a special motor is driven, install
an external thermal relay (OCR) between the inverter and motors. Note that the current indicated on the motor rating
plate is affected by the line-to-line leakage current (details in the Instruction Manual (Detailed)) when selecting the
setting for an external thermal relay.
• The cooling effect of the motor drops during low-speed operation. Use a thermal protector or a motor with built-in
thermistor.
• When the difference between the inverter and motor capacities is large and the setting is small, the protective
characteristics of the electronic thermal relay function will be deteriorated. In this case, use an external thermal
relay.
• A special motor cannot be protected by the electronic thermal relay function. Use an external thermal relay.
• Set Pr.9 = "0" for vector-control-dedicated motors (SF-V5RU) because they are equipped with thermal protectors.
• Motor over temperature sensing is not provided by the drive.
 Applicable power supply
For use at an altitude above 2000 m (maximum 2500 m), only a neutral-point earthed (grounded) power supply can
be used.
4 BCN-C22005-988