Siemens 3RU2126-1JC0 Industrial Control Relay

Siemens 3RU2126-1JC0 is a thermal overload relay designed for motor protection in the Siemens 3RU2 family. It provides a main-circuit current rating of 7.0 to 10 A and a Class 10 trip characteristic, intended for mounting on the main circuit side of compatible contactors in frame size S0. The unit includes a single auxiliary contact configuration (1 NO/1 NC) for status signaling and a spring‑loaded auxiliary circuit terminal arrangement, with a reset option described as manual‑automatic. Reset control and wiring are configured to support both automatic and manual reset workflows, depending on installation needs. The relay is commonly used in control panels to guard 3‑phase motors against overheating due to overload, enabling integrated protection when paired with Siemens contactors to form a compact motor-starting assembly. Its design emphasizes reliable protection in industrial automation environments, offering straightforward integration with Siemens S0 frame devices and a compact footprint suitable for panel mounting alongside other protective devices. Overall, 3RU2126-1JC0 delivers targeted overload protection for smaller to mid-size motors, combining precise current sensing with a dependable trip characteristic and a simple signaling path for control logic.