Industrial 4-Ch Ethernet I/O Module (4DI/2AI/4DO) & Modbus Gateway

4CH-IO-ETH Network IO Module is an digital input output and analog input based on Ethernet. The remote IO controller can conveniently connect to Ethernet to realize accessing TCP connection, and web-page. 4CH-IO-ETH are the ideal choices for user realizing remote control and data acquisition.

It based on Ethernet transmission, support Modbus TCP to Modbus RTU, support virtual serial port, can monitor 4 channels digital input, 2 channels analog input and control 4 channels relay output at the same time. The remote IO control and data acquisition use Modbus TCP protocol or Modbus RTU protocol.

Q: Can a SCADA system and a local HMI poll this 4-channel module simultaneously over Ethernet?

A: Yes. The module supports multi-master concurrent access. However, because this is a compact node designed for fast localized control (<30ms response time), we recommend limiting concurrent Modbus TCP client connections to four or fewer to prevent network congestion and timeout errors.

Q: Can the built-in relay outputs (DO) directly drive field motors or large pumps?

A: Not recommended. The internal relays are designed for control-level switching (e.g., indicator lights, small solenoid valves, or alarm buzzers). To drive large industrial motors or heavy inductive loads, you must wire these relay outputs to external, appropriately sized AC contactors or solid-state relays (SSRs). This prevents inrush currents from arcing and destroying the internal contacts.

Q: How do I switch the 2 analog inputs (AI) between 4-20mA and 0-10V?

A: To switch signal types, you need to set up physical jumpers on the internal circuit board as well as the Web UI settings. Before wiring your sensors, always check the jumper positions in the downloads section of the Hardware Installation Guide. If you don’t, you could damage the sampling circuit.

Q: If I just want to connect an old RS485 flow meter to Ethernet, can I use this purely as a gateway without wiring any local I/Os?

A: Absolutely. The Modbus TCP to RTU gateway function operates completely independently of the local I/O acquisition. However, if your upcoming project only requires protocol conversion with zero physical I/O points, specifying our dedicated Serial Communication Servers will be much more cost-effective and space-efficient.

Q: What happens to the field relays if the factory network drops or the master PLC crashes?

A: The module features an industrial communications watchdog timer. If it detects a Modbus TCP heartbeat timeout, all relay outputs (DO) will automatically disconnect or revert to your pre-configured “Safe State.” This critical safety feature completely prevents field equipment from operating out of control during network failures.

📥Documents

[User Manual] Valtoris-4CH-IO-ETH User Manual

⚙️Utilities

[Setup Software] VirCom7.22

👑 Definitive Guide: [ The Ultimate Guide to Remote I/O: Basics, Specs, and Selection ]

🚀 Application Note: [ PLC Alternative: Automating Battery Production with Remote I/O ]

🔄 Looking for a wireless alternative? Check out our [ Wi-Fi & Ethernet Remote I/O Module ] to eliminate local cabling entirely.