X-404™ | Modbus RS-485 Module

The X-404 is a robust web-enabled Modbus controller offering advanced logic and expandable capabilities.
Manual Datasheet

X-404™ | Modbus RS-485 Module

Versatile, Easy Monitoring & Control

The X-404™ is purpose-built to monitor up to 32 Modbus RS-485 devices and/or sensors. It also includes a 1-wire bus for temperature and humidity monitoring.The X-404C offers wireless capability with a built-in, low-power LTE-M cellular radio. Cellular models with an annual data plan include a dual SIM that provides combined coverage through AT&T and T-Mobile, automatically switching between the two for the best coverage.

Modbus RS-485 input
Up to 16 temperature sensors
Cellular version available

Cellular-Enabled I/O for Remote Monitoring

No WiFi Necessary 
Cellular simplifies your installation and fits where no wired infrastructure exists. There’s no need for third-party resources or IT intervention—everything you need from a PLC is included with the X-404C.

Primary or Backup
With the X-404C, you have the option to use Ethernet as the primary connection to the network and cellular as a failover. This allows logging, remote access, and email alerts even if Ethernet fails.

Built-In Connectivity
The X-404C includes an omnidirectional antenna for use with the embedded LTE-M cellular radio. The antenna is FCC compliant and will not cause interference when installed correctly.

Configurable Status Page
Powered by a lightweight, built-in user interface. Cellular devices have additional settings within the UI where users can review their signal strength, see registration status, set cellular mode and ping interval, and more.

Combined network coverage map for ControlByWeb cellular devices

Streamline your monitoring with the X-404™!

Track up to 32 Modbus RS-485 devices and sensors, plus temperature and humidity via the 1-Wire bus. Upgrade to the X-404C for wireless connectivity with a built-in cellular modem. Enhance your system’s capabilities today!
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Monitor any sensor or equipment that has an RS-485 output with the X-404. It functions as a web-based, cloud-compatible Modbus master for third-party RS-485 modbus sensors and devices. This includes level, current , pressure, temperature, and humidity sensors

Features

Email Notifications
Customizable Web-Based Dashboard
Peer-to-Peer Communication
Conditional Logging & FTP Log Exports
400 Series Platform
Failover From Ethernet (X-404C Only)

Applications

Sensor & Equipment Monitoring
Generator Monitoring
Temp & Humidity Monitoring
Tank Level Monitoring

RS-485 Connector

Sensors Supported: Up to 32
Connector: 5-position, removable terminal strip, 3.81 mm spacing
Communication: RS-485

Temperature Sensors

Maximum Number of Sensors: 16
Temperature Range: -67°F to 257°F (-55°C to +125°C)
Accuracy: ±0.5°C (from -10°C to +85°C)
Sensor Functions: Monitor Temperature, Log Temperature, Email Alerts, SNMP Traps
Humidity Type: ControlByWeb Model X-DTHS-P sensor
Humidity Range: 0-100% RH
Accuracy: ±2%
Max Cable Length: 600 feet (180m) maximum combined cable length

Remote I/O

The X-404 can seamlessly communicate and share I/O with any other 400-series module through the TCP/IP network. This remote I/O can be used by the module for any function and works the same as if the I/O was directly connected