The braking resistor burns to redness is because during motor brake period, it turns to power generation state and the re-generated electrical energy increase the DC bus voltage, the
variable frequency drive for their own protection needs to open the brake function, the extra energy is consumed by the brake resistor, in order to control the DC bus voltage stay in a reasonable range.
Therefore, when the braking resistor burns to red, it is important to cut off the AC drive load. After the load resection, the DC bus voltage will go down in normal circumstance, braking resistor will be removed and the resistor is no longer generate heat energy. If the braking resistor is still turned on, disconnect the variable frequency AC drive's input power.
The best way to solve such problem is configure a suitable braking resistor according brake energy consumption, or set a reasonable braking time base on braking
resistor configuration. The longer braking time, the smaller the braking resistor energy consumption.
