Transient suppression for 342V DC rails
The 1.5KE400CA_R2_00001: Its 380V minimum breakdown voltage triggers conduction before the surge reaches the protected circuit, and the 548V maximum clamping voltage at 2.8A peak pulse current (10/1000µs waveform) defines the voltage the load must survive.
Obsolete — sourcing through surplus channels
Panjit has marked the 1.5KE400CA_R2_00001 as obsolete.
Clamping voltage and the protection margin
The 548V clamping voltage at 2.8A peak pulse current sets the upper limit the downstream components must withstand. For a 342V rail, this provides roughly 60% headroom above the working voltage — adequate for most industrial transient environments, but the margin narrows if the load has a lower absolute maximum rating. The bidirectional channel means a single device clamps both polarities, simplifying BOM count on symmetrical DC buses.