Siemens – 3UG3511‑1BQ50 – Sirius 3‑Phase Sequence & Failure Monitoring Relay

The Siemens 3UG3511‑1BQ50 (Sirius family) is a slim (22.5 mm) DIN-rail mount monitoring relay that detects phase sequence errors, phase loss, and voltage imbalances in three-phase systems. It automatically trips on faults, protecting motors and loads from damage.

Key Specifications:

• Model: 3UG3511‑1BQ50 (Sirius Series)  

• Function: 3-phase sequence, phase failure, phase loss, and asymmetry monitoring ()

• Supply Voltage: 3 × 200…460 VAC, 50/60 Hz  

• Contact Configuration: 2 × changeover (SPDT) contacts rated 8 A @ 250 VAC; 1/3 HP @ 240 VAC  

• Connection: Screw terminals

• Width: 22.5 mm slim design  

• Housing: DIN‑rail mount, IP20

• Weight: ~0.12 kg