Product Description

Siemens Thermal Overload Relay, SIRIUS 3RU2 Series, Motor Protection Relay, Variant DB0 – 3RU2116-0DB0

The Siemens 3RU2116-0DB0 is a compact and highly reliable thermal overload relay from the proven SIRIUS 3RU2 Series, engineered to provide accurate motor protection against overload conditions, phase failure, and excessive current draw. Featuring an adjustable current setting range of 0.22–0.32 A, Class 10 tripping characteristics, and compatibility with Size S00 Siemens contactors, this relay is ideally suited for protecting low-current three-phase motors used in industrial automation, OEM machinery, HVAC systems, process control equipment, and compact motor-driven applications. The 0.22–0.32 A setting range is listed within Siemens S00 thermal overload relay variants.

Built on Siemens’ inverse-time thermal protection technology, the relay continuously monitors motor current and disconnects the motor when overload conditions exceed safe operating limits. This helps prevent motor winding damage, insulation deterioration, overheating, and costly downtime while allowing normal motor starting currents. Integrated phase-failure sensitivity provides enhanced protection against phase imbalance and phase loss conditions. SIRIUS 3RU2 relays are designed for motor protection applications with Class 10 tripping characteristics and direct contactor mounting.

The Variant DB0 offers an adjustable overload release setting of 0.22–0.32 A, making it suitable for fractional horsepower motors, dosing systems, laboratory equipment, compact conveyors, small pumps, ventilation units, packaging machinery, and precision automation equipment. Its compact S00 frame size enables efficient installation in motor control centers (MCCs), switchboards, and industrial control panels.

Designed for direct mounting on compatible Siemens contactors, the relay incorporates 1 Normally Open (NO) and 1 Normally Closed (NC) auxiliary contact for signaling, monitoring, and control circuit integration. It supports both manual and automatic reset modes and features screw-type terminals for secure electrical connections and simplified installation. Siemens SIRIUS overload relays are rated for applications up to 690 V AC and are designed for long-term industrial operation.

Manufactured according to Siemens’ stringent quality standards, the 3RU2116-0DB0 delivers dependable long-term performance and precise protection for low-current motor applications.

Key Features

• Genuine Siemens SIRIUS Product
• Part Number: 3RU2116-0DB0
• Thermal Overload Relay
• SIRIUS 3RU2 Series
• Variant DB0
• Adjustable Current Range: 0.22–0.32 A
• Size S00 Design
• Class 10 Trip Characteristic
• Direct Contactor Mounting
• Manual and Automatic Reset
• 1 NO + 1 NC Auxiliary Contacts
• Phase Failure Protection
• Inverse-Time Delayed Overload Protection
• Screw-Type Main and Auxiliary Connections
• Rated Insulation Voltage up to 690 V AC
• Compact Industrial Design
• Precision Low-Current Motor Protection

Typical Applications

• Small Motor Protection
• Industrial Automation Systems
• OEM Machinery
• Laboratory Equipment
• Dosing Systems
• Compact Pump Controls
• Ventilation Systems
• Packaging Machinery
• Process Control Equipment
• Motor Control Centers (MCCs)