GE Industrial Solutions AF-650 GP General Purpose Drive - Manual (Page 8)

3 Introduction
3.1.1 Description of the Brake System
When the speed reference of a frequency converter is reduced, the motor acts as a generator and brakes. When a motor acts as a generator, it supplies energy
to the frequency converter which is collected in the intermediate circuit. The function of the brake resistor is to provide a load on the intermediate circuit during
braking, thereby ensuring that the braking power is absorbed by the brake resistor.
If a brake resistor was not used, the intermediate circuit voltage of the frequency converter would continue to increase, until it cuts out for protection. The advantage
of using a brake resistor is it enables braking of a heavy load quickly, e.g. on a conveyor belt.
GE has chosen a solution in which the brake resistor does not form an integral part of the frequency converter.
This offers the user the following advantages:
- The resistor time cycle can be selected as required
- The heat developed during braking can be conveyed beyond the panel cabinet to allow the energy to be used
- There is no overheating of the electronic components, even if the brake resistor is overloaded
GE offers a range of brake resistors for AF-650 GP.
This Design Guide describes how to choose the right brake resistor for an application. Alternative to using a brake resistor there are other braking methods which
can be applied depending on the braking profile of the application. The alternative braking methods can be found in the chapter Alternative Braking Methods.
AF-650 GP Brake Resistor Design Guide
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