1500 W peak pulse — what the rating means on the line
The 1.5KE22A/B: That 1500 W rating means it can clamp a transient up to 49.7 A peak pulse current without failing — useful for protecting a 24 VDC control bus or a 18.8 V rail from inductive load dumps or lightning-coupled surges.
Clamping numbers that decide fit
Reverse standoff is 18.8 V — the TVS stays off below that, so it won't load a nominal 18 V rail. Breakdown starts at 20.9 V minimum, and clamping maxes at 30.6 V at the full 49.7 A pulse. That 30.6 V clamp is what the downstream silicon sees; if the protected IC's abs-max is 32 V, there is about 1.5 V of margin at the worst-case pulse.
DO-201 axial — field-swap friendly
Through-hole DO-201AA / DO-27 axial package. Polarity is marked by the cathode band — no orientation guesswork on a board rework. Can be swapped on site with basic hand tools; no hot-air station needed.