SIEMENS Nadprúdové relé 17-22 A 3RU2126-4CB0 (3RU21264CB0)

Thermal overload relay with a current setting range of 17–22 A, tripping class 10, and 3-pole design for reliable motor protection.

Overview

The SIEMENS 3RU2126-4CB0 is a thermal overload relay from the SIRIUS series, size S0. It is designed for direct mounting to contactors such as the 3RT2.2 or for stand-alone installation. The relay provides protection against overloads and phase failure, with manual/automatic reset and screw terminals.

What stands out

• Current setting range: 17–22 A
• Tripping class 10
• 3-pole main circuit
• 1 NO + 1 NC auxiliary contacts
• Rated insulation voltage 690 V
• Manual/automatic reset

Technical details

• Type of overload release: Thermal
• Current setting range: 17–22 A
• Tripping class: CLASS 10
• Size: S0
• Number of poles: 3
• Auxiliary contacts: 1 NO + 1 NC
• Rated insulation voltage (Ui): 690 V
• Rated impulse withstand voltage (Uimp): 6 kV
• Mounting type: Direct mounting to contactor (e.g., 3RT2.2) or stand-alone installation
• Reset function: Manual/Automatic
• Connection type: Screw terminals
• Degree of protection (main circuit): IP00
• Degree of protection (terminals): IP20
• Operating temperature range: -20 to +60 °C
• Rated operational voltage (Ue): 690 V AC
• Power loss (at Ie): 7.2 W
• Standard: IEC 60947-4-1, IEC 60947-5-1

Our verdict

A robust thermal overload relay for motor protection in industrial applications, offering precise current adjustment and reliable tripping.