Microprocessor based overload relay - 3RB (Class 20E) - 3RB3016-2SB0

Product Description

Siemens 3RB3016-2SB0 Electronic Overload Relay – Class 20E Motor Protection for Heavy Starting Applications

The Siemens 3RB3016-2SB0 Electronic Overload Relay is a microprocessor-based motor protection device from the renowned SIRIUS 3RB3 series, designed to provide reliable protection for three-phase motors against overload, phase failure, and phase imbalance conditions. Engineered for industrial automation and motor control applications, this electronic overload relay delivers precise inverse-time delayed protection and helps prevent costly motor damage caused by excessive temperature rise due to overload conditions. Siemens SIRIUS 3RB electronic overload relays are specifically designed for both normal and heavy starting motor applications.

Featuring a 3A to 12A adjustable current range and a Class 20E tripping characteristic, the Siemens 3RB3016-2SB0 is ideal for motors that experience extended startup times or high-inertia loads. Applications such as conveyors, mixers, crushers, compressors, pumps, and material handling systems often require longer acceleration periods. The Class 20E characteristic allows these motors to start normally while still ensuring dependable protection against prolonged overload conditions. Similar Siemens Class 20E overload relays are specifically intended for heavy starting loads and inverse-time delayed protection.

Unlike traditional thermal overload relays that rely on bimetallic elements, the 3RB3016-2SB0 uses advanced electronic current sensing and microprocessor-controlled evaluation technology. This intelligent protection system continuously monitors motor current and thermal behavior, providing significantly greater protection accuracy, improved repeatability, and reduced sensitivity to ambient temperature fluctuations. By detecting abnormal operating conditions before motor windings are damaged, the relay helps extend equipment life and minimize maintenance costs.

The relay provides an adjustable current setting range of 3A to 12A, making it suitable for protecting a wide range of industrial motors. Its electronic protection technology accurately simulates motor thermal conditions and provides inverse-time tripping characteristics that closely match real motor heating behavior. This ensures effective protection while minimizing nuisance trips during normal operation.

A key safety feature of the Siemens 3RB3016-2SB0 Motor Protection Relay is its integrated phase failure and phase imbalance protection. The relay continuously monitors all three motor phases and automatically disconnects the motor if a phase loss or significant imbalance occurs. This proactive protection helps prevent overheating, winding damage, and premature motor failure caused by abnormal supply conditions.

Designed for direct mounting onto compatible Siemens contactors, the relay features a compact design that helps optimize control panel space while simplifying installation and maintenance. Durable screw-type terminals for both the main and auxiliary circuits ensure secure electrical connections and long-term reliability in demanding industrial environments. Similar Siemens SIRIUS overload relays provide contactor mounting, screw terminals, and manual/automatic reset functionality.

For enhanced monitoring and control integration, the relay includes 1 Normally Open (1NO) and 1 Normally Closed (1NC) auxiliary contacts. These contacts can be used for overload trip indication, PLC interfacing, alarm signaling, remote monitoring, and control circuit interruption. This configuration simplifies panel wiring while improving diagnostics and system visibility.

The Siemens 3RB3016-2SB0 supports both manual and automatic reset functions, allowing users to choose the most suitable reset method for their application. Automatic reset minimizes downtime in automated systems, while manual reset provides enhanced operational safety where operator confirmation is required before restarting equipment.

Built according to international industrial standards, the relay offers reliable operation across a wide temperature range, integrated temperature compensation, and robust protection performance. Its compact construction and proven Siemens engineering make it suitable for manufacturing plants, HVAC systems, water treatment facilities, packaging machinery, food processing equipment, and industrial automation projects.

At SBsmart.in, we supply genuine Siemens industrial automation and motor protection products trusted by OEMs, panel builders, electrical contractors, and maintenance professionals across India. The Siemens 3RB3016-2SB0 Electronic Overload Relay delivers dependable motor protection, enhanced safety, and long-term operational reliability.