Appendix: Resistor braking 389
Appendix: Resistor braking What this chapter contains The chapter tells how to select the brake resistor and cables, protect the system, connect the brake resistor and enable resistor braking.
Planning the braking system Selecting the brake resistor ACS355 drives have an internal brake chopper as standard equipment. The brake resistor is selected using the table and equations presented in this section. 1. Determine the required maximum braking power PRmax for the application. PRmax must be smaller than PBRmax given in the table on page 390 for the used drive type. 2. Calculate resistance R with Equation 1. 3. Calculate energy ERpulse with Equation 2. 4. Select the resistor so that the following conditions are met: •
The rated power of the resistor must be greater than or equal to PRmax.
•
Resistance R must be between Rmin and Rmax given in the table for the used drive type.
•
The resistor must be able to dissipate energy ERpulse during the braking cycle T.