What the 1500W rating means for your circuit
The 1.5KE47HE3/73: That 1500W figure is the peak power the device can absorb during a transient — it clamps a 22.1A surge to 67.8V maximum, protecting downstream electronics from voltage spikes that would otherwise exceed the 38.1V reverse standoff level.
Automotive-grade transient protection
The breakdown voltage starts at 42.3V minimum, with the clamping ceiling at 67.8V. For a 12V or 24V automotive rail, the 38.1V standoff gives headroom above the nominal bus voltage while the clamping voltage stays below the abs-max rating of typical downstream regulators and ECUs.
Housed in a DO-201AA (DO-27) axial-lead package, the 1.5KE47HE3/73 is a through-hole part. The axial leads suit point-to-point wiring or through-hole PCB mounting — the body diameter and lead spacing are standard for this power class, so the pad layout follows the DO-201AA footprint common across the 1.5KE series.
Sourcing an obsolete automotive TVS
Vishay lists the 1.5KE47HE3/73 as obsolete.