The Siemens 3RQ4118-1AF01 is an output coupler with a plug-in relay, part of the SIRIUS 3RQ4 family of narrow-design coupling relays. It provides one change-over contact rated for a thermal current of 6 A, controlled by a 230 V AC/DC coil. The screw-terminal connection and 6.2 mm width suit dense DIN-rail panel layouts where isolation between control and load circuits is needed. The hard gold-plated contacts are specified for switching low-level signals where oxidation resistance matters — common in PLC output isolation or signal-level interposing relay applications. The 230 V AC/DC coil voltage covers both line-voltage control signals and DC pilot circuits without needing a separate coil variant.
Compliance documentation is on record: RoHS conformity effective 26 September 2024, and REACH Article 33 notification for lead (CAS 7439-92-1) above 0.1% w/w.
The plug-in relay can be replaced without removing wiring, which simplifies troubleshooting or coil-voltage changes in the field.