Pilz 312070AA PSSU H PLC1 FS SN SD Safety Module

The Pilz 312070AA is a PSSuniversal safety controller module designated as PSSU H PLC1 FS SN SD. This module serves as a fail-safe programmable logic controller (PLC) within the PSSuniversal system, which is used for safety-related automation tasks. It is certified to SIL3 (IEC 61508) and PL e (ISO 13849-1). The module features a high-performance processor, integrated safety I/O, and communication interfaces. It is part of the PSSuniversal head station that connects to standard I/O modules via the PSSuniversal backplane. The device is used for machine safety, emergency stop monitoring, light curtain evaluation, and other safety functions in industrial machinery.

Technical Specifications

Power supply: 24V DC (20.4-28.8V), consumption 250 mA typical. Safety inputs: 16 digital inputs (24V DC, Type 3). Safety outputs: 8 solid-state outputs (PNP, 0.5A each). Test outputs: 4 (PNP, 0.1A). Processor: 32-bit, with integrated safety logic. Memory: 1 MB Flash, 256 KB RAM. Programming: Pilz PAS4000 (IEC 61131-3 FBD/LD). Communication: built-in Ethernet (Modbus TCP) and RS-485 (for PSSuniversal bus). Dimensions: 120 mm × 45 mm × 110 mm. Weight: 220 g. Operating temperature: -10°C to +55°C. Storage: -25°C to +70°C. Protection rating: IP20.

Key Features

• Fail-safe programmable safety controller for PSSuniversal

• 16 safety inputs, 8 safety outputs, 4 test outputs

• SIL3 / PL e certified

• Integrated Ethernet port (Modbus TCP) for diagnostics

• PAS4000 software (FBD/LD) for logic programming

• Expandable with PSSuniversal I/O modules

• LED indicators for status and diagnostics

• Removable screw terminal blocks

Safety Functions

The module can implement a wide range of safety functions including emergency stop, guard door monitoring, two-hand control, light curtain evaluation, and speed monitoring (with external encoders). The safety logic is programmed using PAS4000 software, which includes certified function blocks. The integrated safety outputs are suitable for directly controlling contactors or safety relays. The test outputs can be used for OSSD pulsing or cross-circuit detection.

Integration into PSSuniversal System

The 312070AA acts as the head station for a PSSuniversal I/O system. It mounts on a DIN rail and connects to the system backplane. Up to 64 I/O modules can be added on the right. The module communicates with a higher-level control system (e.g., standard PLC) via Modbus TCP or via the PSSuniversal bus. The safety PLC and standard PLC can exchange status information.

Programming and Configuration

Programming is done with Pilz PAS4000 software (versions 1.0 to 2.0). The user creates safety programs using function block diagram (FBD) or ladder logic (LD). Pre-certified function blocks are available for common safety applications. The program is downloaded via Ethernet or the diagnostic interface. The software also allows online monitoring and debugging. The module stores the program in non-volatile memory.

Applications

The PSSU H PLC1 FS SN SD is used in machinery safety systems such as packaging equipment, robotics cells, conveyor systems, printing presses, and automotive assembly lines. The integrated I/O reduces wiring and component count.

Installation and Wiring

Mount the module on a DIN rail. Connect 24V DC power to the terminals. Wire safety inputs (e.g., emergency stop buttons, safety switches) to the input terminals (I0 to I15). Wire safety outputs (O0 to O7) to the load (e.g., contactor coils). Use separate 24V supply for outputs if needed. Connect test outputs to test inputs of light curtains or OSSD devices. The Ethernet port is used for programming and diagnostics. The module includes status LEDs for power, run, fault, and I/O.

Maintenance and Diagnostics

The module has self-diagnostics and will go to a safe state if an internal fault is detected. The front LED indicates the status: green for run, red for fault. Diagnostics can be read via the programming software. No regular maintenance is required.

Environmental and Compliance

The 312070AA is CE, UL, TÜV certified. RoHS compliant. Operating temperature: -10°C to +55°C. Humidity: 10-90% non-condensing. Protection rating: IP20.

Conclusion

The Pilz 312070AA PSSU H PLC1 FS SN SD safety controller provides a powerful, flexible platform for implementing safety logic in industrial machinery. Its integrated I/O and certification up to SIL3 make it suitable for demanding safety applications.