Clamp voltage and breakdown window
The 1.5KE62-B: Breakdown is guaranteed between 55.8 V (minimum) and the clamping maximum of 89.25 V — a 33 V window that ensures the TVS starts conducting well before the rail hits destructive levels. The 17.9 A peak pulse current at clamp is the current the diode must sink; a 48 V rail hit with a transient that exceeds this current will see the voltage rise above 89.25 V, so the upstream fuse or breaker must clear before the TVS reaches its thermal limit. At the hot end, leakage current through the Zener junction rises, but the 1.5 kW rating is derated linearly above 25°C per the datasheet curve; at 175°C the effective power handling drops to near zero, so the transient must be short or the ambient must stay below the derating threshold.
Obsolete — sourced through surplus channels
Littelfuse lists the 1.5KE62-B as Obsolete. For a BOM that already carries this order code, the existing board layout and clamp voltage are locked — a substitute would require re-qualifying the clamping threshold.