Siemens 3RU21464JB1 Thermal Overload Relay

Product Description

The SIEMENS 3RU21464JB1 is a thermal overload relay designed to protect three-phase motors from sustained overcurrent conditions, phase loss, and thermal overload faults. It monitors motor current continuously and trips the control circuit when heat buildup exceeds the safe operating threshold, preventing winding damage and unplanned downtime. The relay is sized for industrial panel and motor-control-center (MCC) applications and is installed by licensed electricians or qualified industrial maintenance technicians. Its compact footprint suits busbar-mount or direct-mount configurations typical in motor branch circuit assemblies.

This thermal overload relay is used in industrial and commercial motor control applications where reliable overcurrent protection is required. Typical installations include motor control centers, combination starters, and panel-mounted starter assemblies protecting pumps, fans, compressors, and conveyor drives. It is suited for both new installations and replacement service work in facilities requiring IEC-style motor protection components.

Key Features

• Thermal overload trip mechanism protects motors from overcurrent and phase-loss conditions
• IEC-style form factor for direct integration with compatible contactor and starter assemblies
• Manual and automatic reset options typical of this relay class
• Compact housing measures 4.961 inches long by 3.150 inches wide by 5.866 inches tall
• Lightweight construction at 1.733 pounds for easy panel installation

Compatibility

Designed as an OEM-style IEC thermal overload relay for use in industrial motor control and starter assemblies. No specific compatible model numbers were provided in the product data.

Installation Notes

Installation should be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and applicable local codes. De-energize and lock out the motor branch circuit before installing or replacing the relay. Verify that the relay current range matches the full-load amperage of the motor being protected before placing the circuit back in service. Do not bypass or jumper the overload relay contacts during testing.

Technical Specifications

• Product Type: Thermal Overload Relay
• Length: 4.961 inches
• Width: 3.150 inches
• Height: 5.866 inches
• Weight: 1.733 pounds
• UPC: 80476640701
• Quantity per Pack: 1

Standard Information

• Brand: SIEMENS
• Manufacturer Part Number: 3RU21464JB1