Siemens 3RV2021-1JA10 Motor Protection Circuit Breaker

Siemens 3RV2021-1JA10 is a compact, DIN-rail–mounted motor protection circuit breaker (MPCB) designed to provide both overload and short‑circuit protection for three‑phase motors. It is a size S0 device intended specifically for motor protection and is listed with a Class 10 A‑release and an A‑release range of 7–10 A, plus a N‑release at 130 A, with screw‑terminal connections for straightforward panel wiring. The main and auxiliary circuits are rated for 400 V, enabling use on typical European motor power networks, and the unit accepts operation across a broad AC range up to 690 VAC for many industrial motors. This Siemens MPCB supports standard switching capacity and is commonly used in control panels where motor protection is required, often in conjunction with 3RV2 motor starters for integrated protection in compact drive and machine layouts. By combining motor overload protection with short‑circuit protection in a single, DIN‑rail‑mountable device, the 3RV2021‑1JA10 helps protect motors such as pumps, conveyors, and tooling machines while simplifying wiring and panel space requirements.