As modern Automation Technology rapidly evolves toward "decentralization" and "wireless," traditional hardwiring faces severe bottlenecks, including high costs, difficult maintenance, and restrictions on mobile equipment. Currently, a highly mature wireless substitution route has formed within the industrial automation sector. From underlying RF modules (e.g., the E22/E77 series) to industrial-grade finished terminals (e.g., the E90-DTU with up to 70km transmission, P31 series Profinet Distributed I/O, and multi-protocol smart gateways), full-stack communication support is now available. This architecture seamlessly integrates with mainstream industrial bus protocols such as Modbus RTU/TCP, Profinet, and CAN, achieving millisecond-level, highly reliable wireless closed-loop transmission for automation control commands and sensor data.

1. Why Does Automation Technology Urgently Need Industrial Wireless Communication?

The core of automation control lies in the real-time closed loop of "Perception-Decision-Execution." With the advancement of flexible manufacturing and smart factories, the physical pain points of wired solutions have become increasingly prominent:

  1. Cable Aging & Mobility Restrictions: In high-frequency mobile nodes like AGVs, robotic arms, and overhead cranes, slip rings or drag chain cables are highly prone to mechanical wear and tear, leading to downtime and network disconnections.

  2. Exorbitant Cross-Regional Deployment Costs: In wide-area scenarios such as petrochemical parks and water pipe networks, the civil engineering cost of trenching and wiring often far exceeds the hardware cost of the automation equipment itself.

  3. Difficulties in Expanding Legacy Systems: When adding new data acquisition nodes to existing PLC systems, repulling cables through conduits can severely disrupt the normal operation of current production lines.

Deploying a highly reliable industrial wireless communication architecture not only reduces engineering deployment costs by over 70% but also completely breaks physical space constraints, granting automation systems ultimate network topology flexibility.

2. Industrial-Grade Core Hardware Built for Automation Technology

Conventional consumer-grade communication modules are inadequate for the complex electromagnetic environments (e.g., high-frequency radiation from VFDs) and stringent timing requirements of industrial sites. Below are the four core hardware pillars widely embedded into industrial automation systems today:

2.1 Industrial-Grade Wireless Data Transfer Units (DTU): Breaking the Distance Limits of Wires

For master/slave automation equipment already equipped with RS485/RS232/TTL interfaces (such as mainstream PLCs, Variable Frequency Drives, and HMI touch screens), utilizing devices like the E90-DTU series wireless transceivers is the mainstream engineering choice.

  • Core Parameters: Based on LoRa spread-spectrum anti-interference technology, the maximum Line-of-Sight (LoS) communication distance reaches up to 70km.

  • Automation Adaptability: Supports unlimited packet length and continuous transmission, perfectly adapting to the strict timing requirements of the Modbus protocol. Built-in hardware surge protection and anti-static isolation ensure data is output "exactly as received" even in server rooms or workshops with severe electromagnetic interference.

2.2 Industrial Network Protocol Conversion Gateways: Bridging IT and OT Data Silos

During system upgrades, automation networks frequently encounter a mixture of serial buses and industrial Ethernet.

  • Deep Profinet & Modbus Integration: Industry-standard PN1 series gateways (such as the PN1-D25P) execute bidirectional, millisecond-level protocol conversion between Profinet and Modbus RTU. Supporting wide voltage input (DC 8-28V), they allow traditional, low-cost serial instruments to seamlessly and compliantly integrate into high-end PLC automation networks, like those from Siemens.

  • Edge Computing & Cloud Connectivity: Advanced smart gateways not only support multi-serial to Ethernet/4G but also feature built-in edge logic processing. They support lightweight protocols like MQTT/HTTP for cloud uplink, acting as the core scheduling hub for production line data.

2.3 Distributed Remote I/O: Precise Perception and Control of Edge Signals

In remote nodes lacking a master PLC, deploying wireless I/O is the preferred solution for acquiring sensor data and controlling actuators.

  • P31/M31 Series Distributed I/O Architecture: Remotely and in real-time, read AI (Analog Input) and DI (Digital Input) signals, and output DO (Digital Output) and AO (Analog Output) commands via Ethernet, 4G, or Wi-Fi links.

  • Scenario Value: Fully supports standard Modbus/Profinet protocols and features "point-to-point signal mirroring" (i.e., inputting a physical digital signal at one end triggers a direct mechanical output at another device kilometers away). This achieves simplified, highly reliable base-layer automation logic without the intervention of a host master station.

2.4 Underlying RF Modules (For Secondary Development)

For automation equipment integrators (OEMs) with independent hardware R&D capabilities, the choice of underlying RF directly determines the final product's industrial-grade performance:

Representative Series Core Architecture / Chip Automation Adaptability Value
E22/E220 Series SX1262 / LLCC68 Delivers ultra-high sensitivity up to -148dBm and supports SPI/UART transparent transmission. The premier underlying choice for developing industrial long-range sensors and wireless valves.
EWM290 Series PAN3060 (Localized Chip) Aligns with critical infrastructure supply chain security strategies. Supports base-layer automatic relay and single-point wake-up, ensuring critical automation projects remain autonomous and controllable.
E77 Series STM32WLE5 SoC Flawlessly compatible with the standard LoRaWAN protocol specification. Provides an excellent power-to-performance ratio, ensuring overseas automation deployments comply with local RF regulations.

3. Automation Technology Typical Deployment Solutions

3.1 Solution 1: Seamless Wireless Networking for Legacy Workshop PLCs

  • Engineering Pain Point: Multiple isolated PLCs in a traditional workshop urgently require data interoperability for line-level collaborative manufacturing. However, the workshop floor is hardened, and halting production to trench cables is prohibitively expensive.

  • Deployment Architecture: Connect an E90-DTU transceiver to the RS485 port of each PLC. Configure the SCADA software for a "one-master, multiple-slave" polling mode.

  • Result: Utilizing the Modbus RTU protocol, the master PLC can wirelessly read the registers of any slave PLC or instrument within a multi-kilometer radius, exactly as if reading a local physical port. The entire installation is plug-and-play and requires zero production downtime.

3.2 Solution 2: Wide-Area Unmanned I/O Control for Large-Scale Water/Agriculture

  • Engineering Pain Point: Reservoir floodgates and main irrigation valves for large farmlands are located extremely far from control centers, often lacking fiber optic or public cellular coverage. Manual inspections are inefficient and highly costly.

  • Deployment Architecture: Deploy P31/M31 Remote Distributed I/O devices at the control nodes, connecting directly to water level sensors (AI) and pump contactors (DO). Equipment status is polled in real-time to the control center via a 4G DTU or a long-range LoRa private network.

  • Result: The system can execute "automated logic control" directly at the edge based on sensor thresholds (e.g., automatically activating a pump when water reaches a warning level) or receive Beyond Visual Line of Sight (BVLOS) commands from the control room, achieving true wide-area unmanned automated operation.

4. Best Practices for Selection and Deployment (Expert Guide)

To ensure the absolute high availability of Automation Technology systems, engineers must strictly adhere to the following specifications during field deployment:

  1. Protocol Timing Compensation (Timeout Optimization): Industrial protocols like Modbus RTU are highly sensitive to inter-frame time intervals. When converting from a wired setup to wireless transparent transmission, you must appropriately increase the "Response Timeout" setting in the host software (e.g., SCADA systems or the PLC master) to perfectly offset the over-the-air propagation and baseband processing delays of the wireless link.

  2. Antenna System Deployment Specifications: Industrial sites contain numerous metal shields (e.g., distribution cabinets, large machine tools). It is imperative to use magnetic mount or fiberglass antennas to route the radiating element outside the metal control cabinet. Ensure the antenna's clearance zone is free from large metal obstructions to maximize the RF chip's link budget.

  3. Optoelectronic Isolation & Electrical Protection: When connecting to high electromagnetic noise sources like high-power VFDs or servo motors, it is highly recommended to use wireless transceivers and gateways equipped with optoelectronic isolation. This effectively blocks ground loop currents from destroying communication interfaces, ensuring the automation network runs stably 24/7 without requiring a hard reset.

5. Frequently Asked Questions

Q1: How can I replace aging cables with wireless technology without modifying my existing PLC ladder logic code?

A1: You can utilize an industrial-grade data transceiver (like the E90-DTU) that supports full transparent transmission. Once connected to the PLC's RS485 or RS232 port, the device acts as an "invisible, ultra-long serial cable" at the physical layer. Because it supports continuous transmission and unlimited packet lengths, your existing Modbus RTU communication logic will run smoothly without any code changes; you only need to slightly adjust the master station's timeout waiting period.

Q2: Which wireless technology is the most stable in a high-noise factory environment filled with VFDs and motors?

A2: In environments with high Electromagnetic Interference (EMI), solutions utilizing LoRa spread-spectrum technology (such as devices based on the E22 core) are the premier choice. Spread-spectrum technology offers exceptional anti-interference capabilities and the high sensitivity required to extract signals from below the noise floor. Additionally, it is critical to ensure the chosen wireless terminals feature hardware-level optoelectronic isolation and surge protection to physically block electrical noise.

Q3: How do I integrate legacy serial sensors that only support standard Modbus RTU into a newly built Siemens Profinet automation network?

A3: This can be resolved by using a dedicated industrial protocol conversion gateway (such as the PN1-D25P series). These gateways perform hardware-level, real-time bidirectional message parsing and encapsulation. They acquire serial sensor data on one end and mount themselves as standard Profinet IO devices into the hardware configuration of a Siemens PLC (via TIA Portal) on the other, achieving seamless mapping of heterogeneous networks.

Q4: Can we still achieve wireless control if the automation project is in a remote mountainous area or a field pipeline with absolutely no 4G/5G cellular signal?

A4: Absolutely. In this scenario, you do not rely on carrier base stations. Instead, you build a private Point-to-Point (P2P) or Star network by deploying high-power LoRa node modules or finished DTUs. Paired with high-gain directional antennas, you can achieve localized, closed-loop automation control over tens of kilometers in Line-of-Sight environments, completely free of any ongoing data traffic fees.