Chapter 2 Installation ASDA-M2-8 Revision December, 20142.7 Selection of Regenerative ResistorWhen the direction of pull-out torque is different from the rotation, it means the electricity issent back to the servo drive from the load-end. It becomes the capacitance of DC Bus andincreases the voltage. When the voltage increases to a specific value, the come-backeletricity can only be consumed by regenerative resistor. There is a built-in regenerativeresistor in the servo drive. Users can also use the external regenerative resistor if needed.The following table is the specification of built-in regenerative resistor provided by ASDA-Mseries.Servo Drive(kW)Specification of built-inregenerative resistor* 1 The capacity ofbuilt-in regenerativeresistor(Watt)Minimum allowableresistance(Ohm)Resistance(P1-52) (Ohm)Capacity(P1-53) (Watt)0.75 40 60 30 301.5 20 100 50 20* 1 The capacity of built-in regenerative resistor (average value) is 50% of the rated capacityof the built-in regenerative resistor. The capacity of the external regenerative resistor isthe same as the built-in one.When the regenerative resistor exceeds the capacity of built-in regenerative resistor, theexternal regenerative resistor should be applied. Please pay special attention to thefollowings when using the regenerative resistor.1. Please correctly set up the resistance (P1-52) and capacity (P1-53) of theregenerative resistor. Or it might influence the performance of this function.2. If users desire to use the external regenerative resistor, please make sure the appliedvalue is the same as the built-in regenerative resistor. If users desire to connect it inparallel to increase the power of regenerative resistor, please make sure thecapacitance meets the requirements.3. In natural environment, if the capacity of regenerative resistor (the average value) iswithin the rated capacity, the temperature of the capacitance will increase to 120℃ oreven higher (under the condition of regenerative energy keeps existing). For safetyconcerns, please apply the method of forced cooling in order to reduce thetemperature of regenerative resistor. Or, it is suggested to use the regenerativeresistor which is equipped with thermal switches. Please contact the distributors forload characteristics of the regenerative resistor.
