Surge rating and protection envelope
The 1.5KE150CA/B: The minimum breakdown voltage is 143 V, so the device begins conducting between 143 V and the clamp ceiling, giving a defined trigger window for the protection event.
Package and deployment context
Housed in a DO-201AA (DO-27) axial-lead through-hole package, the 1.5KE150CA/B mounts into a PCB with a standard 0.040-inch hole — the lead diameter is about 0.042 inch, so the hole should be drilled 0.045 inch for a solderable fit.