Product Overview
The X20SO2110 (X20SO2110) is a high-precision safe digital output module within the B&R X20 system, specifically engineered for functional safety applications requiring Category 4/PLe or SIL 3 compliance. This module features 2 safe type A digital outputs, each capable of providing 0.5 A of nominal current. By utilizing semiconductor technology, the X20SO2110 ensures that safety-related characteristics remain independent of the number of switching cycles, unlike traditional mechanical relays. It is optimized for controlling safety actuators—such as contactors and valves—in environments where high-speed response and integrated current monitoring are essential for maintaining a safe process state.
Technical Configuration
The X20SO2110 utilizes a "high-side low-side" (Type A) output architecture, which provides a significant safety advantage by enabling the actuator to be cut off in its connection cable under all error scenarios. The module incorporates integrated OSSD (Output Signal Switching Device) test pulses with a duration of less than 500 microseconds to detect short circuits and cross-faults without deactivating the load. Additionally, it features advanced current monitoring for open-circuit detection and is equipped with protection against automatic restarts in the event of network errors. Data is transferred via the openSAFETY protocol, ensuring fail-safe communication across the control network.
Technical Specifications
| Feature |
Specification |
| Model |
X20SO2110 |
| Brand |
B&R (Bernecker + Rainer) |
| Module Type |
Safe Digital Output Module |
| Safety Category |
SIL 3, PL e, Cat. 4 |
| Number of Outputs |
2 Safe Type A (Source/Sink) |
| Nominal Voltage |
24 VDC |
| Nominal Output Current |
0.5 A per channel |
| OSSD Test Pulse |
< 500 microseconds |
| Input Filter |
Integrated with current monitoring |
| Power Consumption |
0.5 W (Internal) |
| Operating Temperature |
0 to 60 deg C (Horizontal mounting) |
| Shipping Weight |
1.5 kg |
Technical FAQs
What are the primary safety benefits of the Type A output variant?
Type A outputs utilize a dual-switching mechanism (high-side and low-side) for each actuator. This ensures that the actuator can be safely disconnected even if one side of the connection cable is shorted to ground or supply voltage, providing superior protection over standard high-side switching.
How does the module detect an open-circuit fault?
The X20SO2110 uses internal current measurement. If the output current drops below 10 mA, the module triggers a "CurrentOK = FALSE" signal. This allows the safety logic to identify broken wires or failed actuators in real-time.
Is this module compatible with standard (non-safety) terminal blocks?
No. To maintain functional safety integrity and prevent incorrect hardware insertion, the X20SO2110 requires a 12-pin safety-keyed terminal block (X20TB12) and a safety-keyed bus module, which must be ordered separately.
Engineering & Installation Guide
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Actuator Grounding Constraints: Because the X20SO2110 is a Type A (high-side/low-side) module, the connected actuators (relays, valves) must not have an existing reference to ground potential. The actuator must be connected exclusively to the two output terminals of the module to allow the safe cutoff logic to function correctly.
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Capacitive Load Management: The module is rated for a maximum capacitive load of 100 nF. When using long cable runs to field actuators, calculate the total cable capacitance. Excessive capacitance can interfere with the OSSD test pulses, potentially causing the module to report false cross-fault errors or enter a fail-safe state.
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Thermal Derating: While the module supports up to 60 deg C in horizontal mounting, vertical mounting reduces the permissible ambient temperature to 50 deg C. For high-density safety racks, ensure a minimum clearance of 12.5 mm is maintained between the safe I/O slice and adjacent high-heat modules to ensure reliable OSSD timing.