The Siemens 3RQ4038-1AE00 is a SIRIUS 3RQ4 coupling relay in the narrow 6.2 mm housing. It integrates a 115 V AC/DC coil with one change-over contact rated for a thermal current of 6 A. This is a signal-level interface relay, not a power contactor — the 6 A thermal current is the continuous carry rating through the closed contact, governing the resistive load it can switch without exceeding temperature rise.
The narrow design is common for coupling PLC outputs (24 V DC) to higher-voltage loads (115 V AC) or for isolating control circuits from field devices.
The product status is listed as Active per the manufacturer's lifecycle record. RoHS compliance is effective from 26 September 2024. The REACH Article 33 declaration notes lead (CAS 7439-92-1) above the 0.1% threshold, which is typical for certain relay internal components and triggers the supply-chain communication obligation for EU end users.