Clamp voltage and power derating in the DO-201 package
The 1.5KE51AHE3_B/C: The 48.5V minimum breakdown voltage ensures the device remains non-conductive below the normal bus voltage, while the 70.1V clamp limits the peak voltage seen by downstream components during a surge. The 1500W peak pulse rating at 25°C derates linearly with ambient temperature — at 175°C the power capability drops to roughly 25% of the 25°C value, so the actual surge current the part can absorb depends on the operating temperature profile. The DO-201AA axial package (also known as DO-27) allows through-hole mounting on a PCB or terminal block, with the lead bend forming the thermal path to the board copper. No power line protection feature is integrated — this is a pure transient suppressor, not a filter or regulator.