Siemens 3RU1146-4EB0 Thermal Overload Relay

Product Description

The SIEMENS 3RU1146-4EB0 is a thermal overload relay designed to protect three-phase motors from overload and phase-failure conditions. It monitors current draw and trips the circuit when sustained overcurrent is detected, preventing motor winding damage. This device is mounted directly onto a compatible contactor or onto a standard DIN rail, making it a common component in motor control centers, panel boards, and industrial control enclosures. Licensed electricians and industrial controls technicians are the typical installers. Its compact footprint and direct contactor mounting reduce wiring complexity and panel space requirements.

The 3RU1146-4EB0 is suited for industrial and commercial motor protection applications where reliable overload detection is required. It is commonly installed in HVAC air handler drive circuits, pump motor controls, compressor starters, and general-purpose three-phase motor control assemblies. This relay fits into motor starter assemblies as an OEM-style or replacement component in industrial control panels.

Key Features

• Thermal overload protection for three-phase motor circuits
• Direct contactor mounting reduces panel wiring complexity
• Compact design suited for DIN rail or contactor-mount installation
• Phase-failure sensitivity helps prevent single-phasing damage to motors
• Manual and automatic reset capability typical of this relay class

Compatibility

Designed as an OEM-style replacement or new-installation thermal overload relay for three-phase motor control applications. No specific compatible model numbers were provided in the product data.

Installation Notes

Installation should be performed by a licensed electrician following applicable NEC requirements. De-energize and lock out the control panel before mounting or wiring the relay. Verify that the relay current range is matched to the full-load amperage of the motor being protected before placing the circuit back in service. Do not power the relay without confirming proper contactor or DIN rail seating.

Technical Specifications

• Dimensions (L x W x H): 4.409 x 2.992 x 5.157 inches
• Weight: 1.208 pounds
• UPC: 75455441254

Standard Information

• Brand: SIEMENS
• Manufacturer Part Number: 3RU1146-4EB0