Clamping voltage and the protection decision
The 1.5SMCJ14CA: The maximum clamping voltage of 23.2V at the peak pulse current defines what the protected node actually sees when a surge arrives — it is the figure that must sit below the absolute-maximum rating of the downstream circuit, not the standoff voltage. A 14V reverse standoff tells you the normal working plane; the 23.2V clamping ceiling is what gates the fit.
The corresponding 64.7 A peak pulse current tells you the current-handling dimension of that event — above this level the diode transitions from protective clamping to destructive failure, so matching the 10/1000 µs waveform to the threat profile (lightning impulse, inductive kick, motor transients) is the sizing step that counts.
Junction temperature margin
The 150°C ceiling gives roughly 50°C of margin above the upper ambient in typical enclosed-panel or industrial enclosures, but layout thermal resistance and surge duty cycle still govern whether the real junction stays clear of that ceiling during a sustained series of transients.
SMC package and tape-and-reel confirmation
The DO-214AB SMC package is the standard industry footprint for this power class — any footprint that accepts a competitor SMC TVS of the same pinout is a candidate. The supplier lists Strip as the package type, which determines how the part ships; confirm tape-and-reel availability and the quantity-per-reel before committing to a production pick-and-place program.