The Yaskawa CDBR‑4045B is a 400 V class dynamic braking resistor unit designed to absorb regenerative energy from up to 45 kW drives (510–660 VDC input, 18 A output). Common failures include overheating of the silicon‑controlled rectifier (SCR) array, tripped thermal overload relays, and degradation of the internal brake resistor due to prolonged high‑current operation. Initial checks should verify that the supply voltage matches the selected class (220 V for S200, 440 V for S400, etc.), confirm that the over‑load relay contacts are closed and not welded open, and inspect the SCRs and resistor for burn marks or discoloration; also review any drive error codes related to “brake overload” or “thermal trip.”[oss-gpt-20b]