Siemens Industrial Controls 3RB3016-1NB0 Relay

The Siemens SIRIUS 3RB3016-1NB0 is a high-performance solid-state overload relay engineered for precise protection of three-phase induction motors. Designed for direct mounting to Siemens S00 size contactors, such as the 3RT2015 through 3RT2018 series, this electronic unit provides a wide 0.32 to 1.25 Amp current range with a 1:4 setting ratio. Unlike traditional thermal relays, this solid-state solution utilizes integrated current transformers to monitor line conditions, offering superior phase failure protection and resistance to phase unbalance. The Class 10E trip characteristic ensures rapid interruption during overload events, protecting motor windings from excessive temperature rises and potential insulation breakdown.

For the field technician, the 3RB3016-1NB0 simplifies commissioning with its adjustable current settings and dual manual/automatic reset functionality. Its internal power supply eliminates the need for external control voltage, while the integrated 1NO + 1NC auxiliary contacts provide immediate fault signaling to the control circuit. This relay is ambient temperature compensated from -25°C to +60°C, ensuring stable tripping profiles regardless of enclosure temperature fluctuations in demanding HVACR and industrial automation environments.

• Universal Mounting: Optimally adapted for direct connection to SIRIUS 3RT2 contactors, reducing cabinet space and wiring complexity.
• Enhanced Motor Safety: Solid-state sensing provides faster response to phase loss and asymmetry than standard bimetallic relays.
• Operational Flexibility: Features a selectable automatic or manual reset and a built-in "test" function for verifying control circuit integrity.
• Wide Application Range: Suitable for 50/60 Hz sinusoidal networks and rated for up to 690V operating voltage.

• Is this relay compatible with all Siemens contactors? It is specifically designed for Size S00 frame contactors (3RT201 series). For larger frames, a different 3RB series size is required.
• Can it protect single-phase motors? No, current-sensing logic in the 3RB30 series requires symmetrical loading across all three phases; use 3RU21 thermal relays for single-phase applications.
• Does it require a separate power supply? No, the electronics are powered internally via the main circuit current transformers.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.