The Siemens 3RF3190-1AA45 is a 1-pole SIRIUS 3RF31 solid-state relay in a 22.5 mm housing, rated for 90 A continuous at 48-600 VAC with a 4-30 VDC control input. The 1200 V blocking voltage means it handles the peak of a 600 VAC sine wave without breakdown — that's the margin that keeps the semiconductor from failing on line transients or switching surges. Because it's a zero-crossing SSR, it switches on near the voltage zero, which limits inrush into resistive or lightly inductive loads like heaters or lamp banks.
Mounting and thermal reality
This relay is designed for mounting on available cooling surfaces — it has no internal heatsink. The 90 A rating is only achievable with an adequately sized external heatsink or panel metal. In a typical DIN-rail enclosure, that means bolting the relay's base plate to a grounded metal backplate or a dedicated heatsink profile.
Compliance documentation
RoHS compliant since 15 January 2024. REACH Article 33 duty to inform applies due to lead content above 0.1% w/w.