Pilz PSS 4000 distributed safety control

2.2 Physical Media and Distance

SafetyNET p supports multiple transmission media to adapt to different industrial environments:

Typical application scenarios for maximum distance of medium type

Twisted pair (CAT5e) 100m cabinet or short distance node interconnection

Multi mode fiber between 5 km workshops, resistant to electromagnetic interference

Single mode fiber optic 32.5 km long-distance cross plant, tunnel, cable car

DSL technology renovation of 10 km old cable without the need for rewiring

In situations where WLAN (IEEE 802.11) line of sight mobile devices, AGVs, etc. cannot be wired

Connectors and cables: It is recommended to use Pilz original RJ45s connectors (model 380 400, working temperature -40~+70 ℃) and CAT5e four core cables (380 000). Prefabricated jumper lengths ranging from 0.5m to 10m are available for selection.

2.3 Coexistence and Routing Capability

SafetyNET p is a 100% standard Ethernet protocol, so it can run in parallel with PROFINET, Modbus/TCP, HTTP and other protocols on the same network without interfering with each other. Simultaneously supporting routing function, commercial switches and routers can be used to divide large equipment networks into multiple network segments for easy maintenance and expansion.

Common network components:

Non managed switches (such as PSSnet SLL 5T): plug and play, suitable for small networks

Management switches (such as PSSnet SHL 8T MRP): support web management, MRP ring network redundancy, and diagnostic functions

Gateway (such as PSSnet GW1 MOD-CAN, MOD EtherCAT): Implement protocol conversion between SafetyNET p and CANopen, EtherCAT subnets

2.4 Network troubleshooting in engineering

When a communication failure occurs, troubleshoot in the following order:

Check physical connection: Is the RJ45 connector securely fastened? Is the cable broken? Does optical fiber have optical power?

Observe if the LED: Link/ACT indicator light on the switch is constantly on? If there is abnormal flashing, there may be packet loss.

Using the diagnostic editor: Open the diagnostic view in PAS4000 software to view the online status, cycle time, and frame loss count of each node.

Check for IP address conflicts: SafetyNET uses MAC based communication, but if TCP/IP services are also used, it is necessary to ensure that the IP addresses are not duplicated.

Ring network redundancy fault: If MRP is enabled, it is necessary to confirm that the ring network management node configuration is correct and all switches support MRP.

Engineering Practice of PAS4000 Software Platform

3.1 Overview of Programming Environment

PAS4000 is a unified engineering platform that integrates configuration, programming, debugging, and diagnostic functions. Its core components include:

Hardware configurator: Define the order and parameters of header modules and I/O modules.

Program Editor:

PASmulti: A graphical editor that allows for the quick implementation of safety functions such as emergency stop, grating, and safety doors by configuring logic through drag and drop connections. Built in rich functional block libraries (FS-Emerger Stop, FS_Light Curtain, FS_Suting, etc.), all security blocks are certified by T Ü V.

PAS IL/STL/LD: Text and ladder diagram editors that comply with IEC 61131-3, used for complex automation tasks and can be mixed with non safety logic programming.

Resource allocator: Allocate various parts of the user program to different physical controllers (resources). This is the key to implementing distributed control: you can write programs first and then map them later without knowing the final hardware layout.

I/O mapping: Associate global variables in the program with actual physical input-output channels.

Diagnostic Editor: Associate diagnostic information (alarm text, recommended measures) for each variable, automatically displayed at runtime.

3.2 Advantages of Hardware Independent Programming

In traditional PLC projects, it is necessary to first determine the hardware configuration (CPU model, I/O address) before writing logic. PSS 4000 supports hardware independent project creation: You can write functional blocks and program structures without hardware, and then allocate resources after hardware configuration is completed. According to Pilz statistics, this method can reduce up to 30% of the project time.

Example scenario: A packaging line has 6 workstations, and initially only 2 controllers are needed. When expanding in the later stage, you don't need to modify the program logic, just move the program segments of workstations 3-6 to the newly added controller in the resource allocator and download them again.

3.3 Software Block Reuse and Standardization

PAS4000 provides three levels of software block libraries:

General safety blocks: emergency stop, grating, safety door, dual hand control, valve monitoring, safety Ethernet connection, etc.

Hardware related blocks: FS_ Absolute Encoder, FS_ Incremental Encoder, FS_ Counter Dual (Position and Speed Safety Assessment), FS_ Analog Input Dual (Redundant Analog Monitoring).

Application related blocks: FS-PressOperatingModes, FS_CamController, FS_SurnerManagement System.

User defined blocks: You can use PAS STL to write your own function blocks, and then call them in PASmulti like built-in blocks. After modification, all instances will be automatically updated with centralized version management.