3RB3036-1UB0 - Siemens Overload Relay (12.5-50 A)

3RB3036-1UB0 - Siemens Overload Relay (12.5-50 A)

If you’re running motors day in and day out, you already know how important dependable overload protection is. The Siemens 3RB3036-1UB0 gives you a straightforward, reliable way to protect your equipment without overcomplicating your setup. This solid-state overload relay uses electronic sensing to monitor current more accurately than traditional thermal devices, helping reduce the risk of overheating and unexpected shutdowns. With an adjustable range from 12.5 to 50 amps, it covers a wide span of motor applications, so you don’t have to stock multiple units for different loads. The CLASS 10E trip characteristic is designed to react quickly when it matters, while still allowing normal startup conditions to pass without nuisance trips. It mounts directly onto S2 contactors, keeping your panel layout clean and efficient. And with manual, automatic, and remote reset options, you can set it up in a way that fits how your operation actually runs.

Key Features and Benefits

• Electronic overload protection (CLASS 10E): Consistent response to overload conditions helps protect motors from damage
• Adjustable current range (12.5–50A): Flexible enough for multiple motor sizes
• Direct contactor mounting (Size S2): Saves space and simplifies installation
• Multiple reset options: Manual, automatic, or remote reset for added control
• Built-in auxiliary contacts: 1 NO and 1 NC for status indication and control integration
• Rated up to 690V: Suitable for a wide range of industrial systems
• Designed for real-world conditions: Handles vibration, temperature swings, and demanding environments

Technical Specifications

• Product Type: Solid-state overload relay (SIRIUS 3RB3 series)
• Current Range: 12.5–50 A
• Trip Class: CLASS 10E
• Rated Voltage: Up to 690 V AC
• Frequency: 50–60 Hz
• Motor Power (400V): 7.5–22 kW
• Motor Power (690V): Up to 45 kW
• Thermal Current: 50 A
• Auxiliary Contacts: 1 NO (trip signal), 1 NC (contactor disconnect)
• Mounting: Contactor-mounted (Size S2)
• Connection Type: Screw terminals (main and auxiliary circuits)
• Ingress Protection: IP20, finger-safe front
• Operating Temperature: -25°C to +60°C
• Dimensions (H x W x D): 99 mm x 55 mm x 104 mm

Material Compliance and Certifications

• Certifications: cULus, CCC, EAC
• Hazardous Location: ATEX compliant
• Marine Approvals: ABS, DNV, LR, PRS, RINA
• Environmental Compliance: Includes SVHC-listed substance disclosures

Where It Works Best

• Industrial motor control panels
• Manufacturing equipment and production lines
• HVAC systems and building automation
• Pumps, compressors, and conveyor systems
• Process control and automation setups