What the 1500W rating means for your protection design
The 1.5KE530-B: That 1500W rating is the peak pulse dissipation — the device absorbs a single transient up to that energy level without failing short. For repetitive surges, derate per the pulse derating curve; the 1.5KE series is a standard workhorse for general-purpose transient suppression on AC mains or DC bus lines where the clamping voltage sits above the normal operating rail. The DO-201 axial package (also known as DO-27) is through-hole, which means it survives rework cycles well — a hot-air station lifts it cleanly if the leads are trimmed short, and the body is large enough to read the marking without magnification.
Obsolete — sourcing through surplus channels
Littelfuse lists the 1.5KE530-B as Obsolete. For a BOM that already qualifies this TVS, the obsolete status means the last-time-buy window has closed. A board spin to a different package or a different Littelfuse series (e.g., the 1.5SMC or SMDJ surface-mount families) may be required for new designs.