The 1.5KE27CA-E3/54: Breakdown occurs at a minimum of 25.7 V, ensuring the diode begins conducting before the protected circuit's absolute maximum rating is reached. The clamping voltage at peak pulse current (40 A) is 37.5 V max — this is the voltage the downstream components must survive during a transient event. A 24 V relay coil or sensor input with a 40 V abs-max rating has margin here.
Sourcing and lifecycle posture
The DO-201AA axial package is through-hole, compatible with automated insertion and hand-solder rework alike.