Siemens 5SY4220-7 Sentron molded‑case circuit breaker is a two‑pole, 20 A protection device designed for 230/400 V AC circuits, offering a 10 kA short‑circuit breaking capacity at 400 V and a C‑type (curve C) trip characteristic for typical inrush loads. As the successor to the older 5SX4220‑7, it features a 70 mm frame width (D70) for compact panel installations, replacing the prior 55 mm version. The unit provides thermal‑magnetic protection with long‑time and instantaneous trip functions, enabling reliable overload and short‑circuit protection in Siemens SENTRON distribution panels and similar installations.
