What the 1500W rating means for your rail protection
The 1.5KE100A: That 1500W figure is the peak pulse power the device can absorb in a single transient event — it is not continuous dissipation. For a 24V or 48V DC bus with a 85.5V reverse standoff voltage, this part stays transparent during normal operation and only conducts when the line spikes above the breakdown threshold of 95V minimum. The 11.1A peak pulse current at the 10/1000µs test waveform tells you the current the diode shunts during the surge. If your transient source impedance is low enough to push more than 11.1A, the device may fail short — so the circuit designer must verify the surge current stays within this limit for the expected transient energy.
Package and board integration
The DO-201AA axial package is a through-hole form factor with a 0.052-inch diameter lead. It mounts into a 0.040-inch plated-through hole on the PCB. The axial leads require bending to a 90-degree angle for vertical mounting or can be left straight for horizontal lay-flat installation. The supplier device package is DO-201, which is the same mechanical outline. The through-hole package is hand-solderable and reworkable, which matters for prototype builds or field repairs where reflow is not an option.