Siemens 3RB2123-4QB0 SIRIUS Thermal Overload Relay - 6-25A
Siemens 3RB2123-4QB0 Overload Relay with Ground Fault Detection.
The Siemens 3RB2123-4QB0 is a thermal overload relay from the SIRIUS 3RB21 series, designed for motor protection with enhanced features. It covers an adjustable current range of 6 to 25 A and is suitable for Size S0 contactors. This relay offers adjustable trip class settings from 5 to 30 and includes internal ground fault detection. It features screw terminals for both main and auxiliary circuits and supports manual or automatic reset. This is a phased-out product; the preferred successor is the 3RB3123-4QB0.
This overload relay is ideal for protecting medium-sized three-phase motors in applications such as pumps, fans, conveyors, and machine tools. The integrated ground fault detection adds an extra layer of safety and protection in installations where ground faults are a concern, common in general manufacturing, water treatment, and HVAC.
Stanlo Automation, a veteran-owned surplus parts distributor, provides the Siemens 3RB2123-4QB0 overload relay. Ensure your motor protection is robust and reliable by sourcing from Stanlo, your go-to for quality surplus components and efficient service.
| Type | Thermal Overload Relay |
| Current Range | 6-25 A |
| Size | S0 |
| Protection Class | Class 5-30 |
| Ground Fault Detection | Internal |
| Mounting | Contactor Mounting |
| Main Circuit Terminals | Screw |
| Auxiliary Circuit Terminals | Screw |
| Reset | Manual/Automatic |