RS Automation OEMax CSD7, User Manual, Page: 264 / 332

9-12
Application
CSD7 Servo Drive (EtherCAT)
Regenerative Braking Resistor
Regenerative Energy
When stopping the running motor, the motor operates like a generator and the resulting
energy is called the regenerative energy.
Regenerative Braking Resistor
The regenerative energy occurring when the motor is stopped is absorbed by the servo
drive in some degree, but if the energy exceeds the capacity, a separate device is needed to
consume the regenerative energy. The regenerative resistor is mounted on the exterior of
servo drive in order to consume the regenerative energy.
If there is excessive regenerative energy that causes the damage to the Servo Drive, but the
Servo Drive is equipped with the protective circuit to shield off such phenomenon.
Generation Condition of Regenerative Energy
•
When the speed is decelerating
•
When the motor is continuously rotated by the strength of the load for example (-
loading condition) or (When of operating the vertical axis loading)
Operating Condition of Regenerative Circuit
•
Turn-on voltage of regenerative circuit : 385Vdc
•
Turn-off voltage of regenerative circuit : 375Vdc
Precaution
Regenerative resistor equipped on the servo drive is designed to consume the regenerative
energy in relatively short period of time such as in between the stops. It is not appropriate
to the case when the regenerative energy is generated too much, like the cases of minus
loading condition and vertical load that rotates the servo motor with the gravity. However,
when the rated power of regenerative resistor that is calculated by referring to the 9-15