Siemens 3RU21160KB0 Overload Relay Class 10

Product Description

The SIEMENS 3RU21160KB0 is a Class 10 thermal overload relay designed to protect three-phase motors from overload and phase-loss conditions. It monitors motor current continuously and trips the circuit when sustained overcurrent threatens motor windings. Class 10 trip timing means the relay responds within 10 seconds at six times the set current, making it well suited for standard induction motor applications. Licensed electricians and industrial maintenance technicians install this relay as part of a motor starter assembly in control panels, switchgear lineups, and machine control circuits.

This overload relay is used in residential, commercial, and light industrial motor control applications where consistent, reliable overload protection is required. It is typically mounted in combination with a contactor to form a complete motor starter. Common install scenarios include pump panels, fan coil unit controls, compressor circuits, and conveyor systems. The compact footprint fits into standard din-rail or direct-mount starter configurations without requiring additional spacing hardware.

Key Features

• Class 10 trip characteristic for standard induction motor protection
• Continuous current monitoring with automatic phase-loss detection
• Compact form factor at 4.016 inches long, 1.929 inches wide, and 3.307 inches tall
• Lightweight construction at 0.331 pounds for easy panel integration
• Designed for direct combination with compatible Siemens contactors

Compatibility

Designed as an OEM-style replacement or new-installation overload relay for three-phase motor starter assemblies requiring Class 10 trip protection.

Installation Notes

Installation should be performed by a qualified electrician in accordance with the National Electrical Code (NEC) and any applicable local codes. De-energize and lock out the circuit before installing or adjusting the relay. Set the current adjustment dial to match the motor full-load amperage listed on the motor nameplate. Do not defeat or bypass the overload relay to restore a tripped circuit without first identifying and correcting the root cause of the overload condition.

Technical Specifications

• Trip Class: Class 10
• Length: 4.016 inches
• Width: 1.929 inches
• Height: 3.307 inches
• Weight: 0.331 pounds
• Package Quantity: 1 per pack
• UPC: 66264392004

Standard Information

• Brand: SIEMENS
• Manufacturer Part Number: 3RU21160KB0