The Siemens load monitoring basic type 3RF2920-0FA08 is a component of the SIRIUS system building kit, specifically designed for monitoring loads in industrial applications. It serves as a base module for current monitoring and is intended for use with semiconductor relays or contactors. The device is designed for a control voltage of 24 V DC and features a switching contact in NO standard (Normal-Open), which switches when the set current value is exceeded. The load monitoring is marked as end-of-life, meaning it is no longer produced in series but remains available.

Applications

The load monitoring basic 3RF2920-0FA08 is used in industrial control systems where continuous monitoring of load current is required. It is particularly suitable for applications where the power consumption of motors, heaters, or other electrical consumers must be monitored to avoid overloads. The device is used in combination with semiconductor relays or contactors, which are controlled via the NO contact. The maximum load current monitoring is 20 A at an ambient temperature of 40 °C, defining the operational limits in industrial environments.

Functions and Equipment in Detail

The module monitors the current flow in a load and switches the NO contact when the set current value is exceeded. The control voltage is 24 V DC, which represents a standard supply in many industrial control systems. The contact is configured as an NO contact, meaning it is open during normal operation and closes when triggered (e.g., in case of overload). The load monitoring is designed as a base module, indicating that it can be used in combination with other modules in the SIRIUS system to achieve extended functions.

Technology Explained Simply

The load monitoring operates with an electronic monitoring mechanism that measures the current flow in the load and compares it to a pre-set threshold value. When this value is exceeded, the NO contact is activated, enabling control of the connected semiconductor relay or contactor. The operating voltage of 24 V DC is a common voltage in industrial control systems and allows for easy integration into existing systems. Current monitoring occurs up to 20 A at an ambient temperature of 40 °C, defining the operating conditions in industrial facilities.

Compatibility and Accessories

The load monitoring basic 3RF2920-0FA08 is specifically designed for use with semiconductor relays and contactors. Suitable accessories include, for example, the load monitoring basic 3RF2906-0FA08 and the load monitoring 3RF3920-0FA08, which also operate in the current range of 20 A / 40 °C. These modules can be combined within the SIRIUS system building kit to achieve extended monitoring functions. Compatibility with other components of the SIRIUS system enables modular expansion of control functions.

Mounting and Installation

Mounting is carried out in the usual manner for SIRIUS modules, for example on a control panel or in an enclosure. Electrical connections are made via the designated terminal clamps, with the control voltage (24 V DC) and load connection wired according to technical specifications. Installation does not require special tools or additional components, as the module is designed as a base unit.

Advantages in Operation

The load monitoring basic 3RF2920-0FA08 provides reliable current monitoring in industrial applications. Integration into the SIRIUS system enables modular expansion of control functions. The use of 24 V DC as control voltage ensures easy integration into existing systems. Monitoring of load current up to 20 A at 40 °C ambient temperature covers a wide range of industrial applications. The module is marked as end-of-life, which should be considered when planning replacement or expansion measures.