The Siemens SIRIUS 3UG3513-1BL50 is a 22.5 mm phase-failure and sequence monitoring relay with two changeover contacts, rated for 3xAC230V at 50/60 Hz. The lifecycle stage is listed as current, meaning it remains in the active catalog for now.
The 3xAC230 V supply voltage tells you this relay monitors three-phase mains without a separate control supply — it powers itself from the lines it watches. The 50/60 Hz rating covers both standard industrial frequencies, so no adjustment is needed for a 50 Hz plant versus a 60 Hz one. The two changeover contacts give you one normally-open and one normally-closed set per contact, enough to signal a fault to a PLC and simultaneously drop a motor starter.
The lifecycle stage is listed as current, so this part is still in the active Siemens catalog. However, the description explicitly calls it a "phased-out product" and gives a replacement type: 3UG4512-1BR20. That means Siemens has designated a successor, and the 3UG3513-1BL50 is in its last phase of availability.