Configuring a Port-Powered RS-232 to RS-485 Converter for VisiSat Communication

[Product_Support]

Issue

How do you configure VisiSat to communicate with MicroNet or IAC controllers using a port-powered RS-232 to RS-485 converter?

Product Line

Field Devices, Satchwell MicroNet

Environment

• Satchwell VisiSat
• Any port-powered RS-232 to RS-485 converter

Cause

Proper configuration of the RS-232 to RS-485 converter is required to establish communication between VisiSat and field controllers.

Resolution

Port-powered RS-232 to RS-485 converters such as the LIB-4-485 allow serial communication between a PC and RS-485-based controllers without requiring an external power supply.

Power Requirements

• Powered directly from the PC’s RS-232 port.
• Ensure the PC’s serial port complies with RS-232 voltage specifications.
• Most modern PCs (e.g., Dell) are compatible, but some laptops or USB-to-serial adapters may not supply sufficient power.

Wiring Guidelines

• TD (A) → Connect to negative (-) terminal of the controller.
• TD (B) → Connect to positive (+) terminal of the controller.
• GND → Connect the shield/screen only at the converter end, not at the controller.

⚠️ Always refer to the converter’s datasheet for pinout and wiring specifics.

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VisiSat Server Configuration

1. Open the VisiSat Server Client from the system tray.
2. Go to Network Menu → Settings.
3. In the Configure Network Settings window:
   • Set Transport Type to Serial Port
   • Click Configure

     

Serial Port Settings

• Choose the appropriate configuration based on the controller type:
  • MicroNet Controllers: Use the following MicroNet-specific settings.

    

  • IAC Controllers: Use the following IAC-specific settings.

    

Click OK to apply settings. VisiSat is now ready to communicate with the controller via the RS-485 converter.

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Additional Notes

• The VisiSat Engineering Guide contains additional information regarding the VisiSat server.

• If using a USB-to-serial adapter, ensure it supports port-powered converters.
• For long cable runs, consider using isolated converters to prevent ground loops.