Siemens Overload relay for motor protection, size S0, 4.5-6.3A Part number 3RU2126-1GB0

Product Overview

Siemens 3RU2126-1GB0 is a SIRIUS 3RU2 series thermal overload relay designed for motor protection in industrial electrical systems. This device offers current-dependent thermal overload protection for three-phase motors. It senses excessive motor current caused by overload or phase loss and triggers a trip to disconnect the motor circuit, helping prevent equipment damage and improving operational safety.

Key Features

• Thermal overload relay for motor protection
• SIRIUS 3RU2 series design
• Adjustable current range: 4.5 … 6.3 A
• Size S0, Class 10 overload trip characteristic
• Main and auxiliary circuits with screw connections
• Manual or automatic reset options
• Screw terminal connections for main and auxiliary circuits
• Compact design compatible with contactor mounting

Technical Specifications

• Article Number: 3RU2126-1GB0
• Product Family: SIRIUS 3RU2 thermal overload relays
• Device Type: Adjustable thermal overload relay
• Adjustable Current Range: 4.5 … 6.3 A
• Overload Trip Class: Class 10
• Size: S0
• Main Circuit Connection: Screw terminals
• Auxiliary Circuit Connection: Screw terminals
• Rated Insulation Voltage: 690 V
• Surge Withstand Voltage (Uimp): 6 kV
• Manual/Automatic Reset: Yes
• Protection Class: IP20
• Weight (approx.): ~0.185 kg
• Operating Temperature Range: –40 °C to +70 °C
• Storage Temperature Range: –55 °C to +80 °C
• Mounting Style: Mountable directly on compatible contactors

Compliance & Certifications

• Manufactured to Siemens industrial protection device quality standards
• Designed and tested to IEC/EN standards for overload relays

Applications

The Siemens 3RU2126-1GB0 thermal overload relay is used to protect three-phase motors against damage caused by prolonged overload, phase loss or imbalance. It is mounted with compatible SIRIUS contactors and is suitable for motor starter combinations in industrial plants, machinery control panels and automation systems where motor protection is required.