What the 1500 W pulse rating means on the bench
The 1.5KE30H: That 36 A peak pulse current at a 43.5 V clamp tells you the part can absorb a substantial energy spike — think load-dump or inductive kickback on a 24 V nominal automotive rail — without letting the protected circuit see more than 43.5 V. The reverse standoff voltage is 24.3 V, so the diode stays out of the circuit below that rail voltage and only starts conducting when the transient pushes past it. This is a unidirectional device — one channel, cathode band goes toward the rail you are protecting.
Graded Automotive and qualified to AEC-Q101, the 1.5KE30H is screened for the reliability stresses an under-hood or chassis-mounted ECU sees — temperature cycling, high-temperature reverse bias, and ESD robustness. The operating junction temperature range spans -55°C to 175°C, covering the full automotive temperature envelope with margin for self-heating during the pulse.
Package and rework considerations
Housed in a DO-201AA (DO-27) axial-lead package, with the supplier device package designated DO-201. The through-hole body is straightforward to hand-solder or wave-solder — the axial leads give good thermal relief during rework, and the cathode band is clearly marked on the body so orientation is unambiguous. No moisture sensitivity level to track; it lives on the shelf as long as the leads stay clean.