It sounds like you have electronic control of the regenerative braking, and what has happened is the switching device that turns on the resistor at the over-voltage point has shorted, this will cause the braking resistor to conduct all the time, normally it is on briefly during braking so it is not a continuously rated component, hence the glow.
It would be my take anyhow.
Al.
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |