What the 1500 W rating means on the board
The 1.5KE250CA_R2_00001: The 214 V reverse standoff voltage means it starts conducting only when the line exceeds that level — normal 200 V bus transients below 214 V pass unclamped. Clamping voltage is 344 V max at the 4.5 A peak pulse current, which sets the voltage the downstream device must survive.
Through-hole DO-201AE axial package — the leads are 0.042-inch diameter, and the body length is about 7.6 mm. The hole diameter on the PCB should be 0.040 to 0.045 inch for a press-fit solder joint. The 1500 W rating assumes the leads are soldered into 1 oz copper pads with at least 30 mm² of copper area per pad to sink the heat from a single pulse.