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X-404 Modbus Master Controller | ControlByWeb
5 Year Warranty

Monitor up to 32 modbus devices/sensors as well as a 1-Wire Bus for Temperature and Humidity Monitoring

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Temp: Up to 16 sensors

Modbus: Up to 32 devices/sensors




9-28 VDC*




Live X-404 Demonstration

For your convenience we have set up a live X-404 unit for testing and evaluation. By clicking the links below you have full access to this live unit. You can make changes to the configuration and settings through the setup pages and you can control X-404 through its control page. The control page allows you to view the current state of the Modbus sensors.

X-404 Setup

The diagram illustrates how this demonstration is wired. An ultrasonic sensor and a Modbus current transducer is connected to the X-404™. You can visit the control page to monitor the values of these sensors.

To test creating logic on the X-404, visit the Setup Pages and access the Control/Logic tab to create schedules and add conditional tasks.

Important Information

  • Multiple users may be accessing this device simultaneously so the device can change while you are using it.
  • This unit will be reset to factory defaults daily at 2:30AM MST.
  • Please DO NOT change network or password settings.
X-404 live demonstration setup


Control Page Setup Pages*

*Setup page login information:

Username: admin

Password: webrelay

Where to Buy

Click "Buy Online" to view part numbers and pricing. X-404 is available in the USA and internationally, and can be purchased either from us or an Authorized Distributor.