The Siemens 3RU2066-1EC2 is a SIRIUS series thermal overload relay engineered to provide reliable motor protection against overload current, phase failure, and excessive thermal rise in industrial motor control applications. Designed for direct mounting with Siemens contactors, the relay utilizes temperature-compensated bimetal technology to ensure dependable tripping performance under varying operating conditions. The unit supports both manual and automatic reset modes and includes integrated auxiliary contacts for fault signaling and control circuit integration. Compact and robust in construction, the overload relay is suitable for MCC panels, industrial automation systems, HVAC equipment, conveyors, and heavy-duty motor protection applications where safe and continuous motor operation is required.
Specifications
| Specification | Value |
| Product Name | Siemens 3RU2066-1EC2 |
| Brand | Siemens |
| Series | SIRIUS 3RU2 |
| Main Category | Electrical & Lighting |
| Sub-Category | Automations |
| Product Type | Thermal Overload Relay |
| Protection Type | Motor Overload & Phase Failure Protection |
| Relay Type | Thermal Bimetal Overload Relay |
| Mounting Type | Direct Contactor Mount |
| Reset Method | Manual / Automatic |
| Auxiliary Contacts | 1NO + 1NC |
| Terminal Type | Screw Terminal |
| Pole Configuration | 3 Pole |
| Protection Class | Class 10 |
| Operating Voltage | Up to 690V AC |
| Standards | IEC / UL / CSA |
| Application | Motor Protection |
| Usage | MCC Panels & Industrial Automation |
| Compatible With | Siemens SIRIUS Contactors |
| Operating Temperature | -20°C to +60°C |
| Industrial Duty | Heavy Duty Industrial Use |