Datalogic SG-BWS-T4-MT Safety Control Unit

The Datalogic SG-BWS-T4-MT is a safety control unit designed for managing machine guarding applications with Category 4, SIL 3, and PL e safety ratings. This compact unit interfaces with up to four pairs of safety photocells or two pairs of light beam protectors, providing reliable safety monitoring for access control, body protection, and perimeter guarding. The SG-BWS-T4-MT includes double muting functionality, allowing temporary suspension of the safety function during workpiece passage while maintaining safety integrity. The plastic-housed unit is designed for OMEGA/DIN rail mounting and features 16 screw clamps for secure wiring connections.

Technical Specifications

Key Features and Benefits

• Safety Integrity Certification: The SG-BWS-T4-MT meets the highest safety certification levels, including Type 4 according to EN 61496-1 for electro-sensitive protective equipment, SIL 3 according to IEC 61508/IEC 62061 for functional safety, and PL e according to EN ISO 13849-1 for performance level classification. These certifications allow the unit to be used in applications requiring the highest risk reduction level, up to and including the protection of personnel from serious hazard exposure.

• Double Muting Functionality: The double muting feature allows temporary, controlled suspension of the safety function while workpieces pass through the guarded area. This eliminates the need for operators to manually bypass the safety system for material throughput, improving production efficiency while maintaining safety integrity. The double muting configuration provides redundancy and ensures that muting only occurs when both muting sensor conditions are satisfied simultaneously, preventing unsafe bypass conditions.

• Multiple Sensor Compatibility: The control unit accepts inputs from up to four pairs of safety photocells and up to two pairs of external light beam protectors, offering flexibility for complex guarding configurations. The unit is compatible with Datalogic S5-ST, SL5-ST, and S300 series safety photocells, enabling integration with existing safety device inventories.

• Dual OSSD and Relay Outputs: The SG-BWS-T4-MT provides two PNP OSSD (Output Signal Switching Device) solid-state safety outputs for controlling external safety circuits, along with two normally open relay outputs. The OSSD outputs are short-circuit protected and achieve a response time of 39 ms maximum, ensuring rapid machine stopping upon safety device actuation.

Functional Overview

The SG-BWS-T4-MT monitors the status of connected safety photocells and external beam protectors. Under normal conditions, the safety outputs are active, enabling machine operation. If the guarded zone is interrupted, the unit disables the OSSD outputs within 39 ms, signaling the machine to stop. When double muting is configured, the unit temporarily suspends the safety function during workpiece transport. The unit also monitors muting sensor logic and will reset safety functions only when the muting sequence completes correctly.

Compatibility and Integration

The SG-BWS-T4-MT supports selection of manual/automatic restart and External Device Monitoring (EDM). It is designed for use in body protection and perimeter access control systems. The control unit is suitable for integration with various safety components including light curtains, safety mats, and two-hand control devices.

Installation and Configuration

The SG-BWS-T4-MT mounts onto OMEGA or standard 35 mm DIN rail inside a control enclosure. Power supply requires 24 VDC ± 15% within the specified power consumption limit. Safety photocells connect to the 16 screw clamp terminals per the wiring diagram in the instruction manual. LEDs on the front display provide status and diagnostic information. Configuration includes selecting single or double muting, enabling or disabling EDM and auto/manual restart.

Maintenance and Reliability

The SG-BWS-T4-MT does not require special servicing under normal conditions. The front optic surfaces of any photocells must be cleaned regularly to prevent reduction of operative distance. Datalogic guarantees the product through a three-year factory warranty. The unit has a MTTFd of 428 years and PFHd of 1.74 × 10^-9 per hour, supporting safety system validation calculations for machine builders and safety engineers.

Conclusion

The Datalogic SG-BWS-T4-MT safety control unit provides high-integrity machine guarding with Type 4, SIL 3, PL e certification. Its double muting capability, multiple photocell inputs, PNP OSSD outputs, and compatibility with Datalogic safety sensors make it a suitable solution for applications requiring personnel protection with automated workpiece transfer.