📝 Description

Used and tested product. Original Fronius COM-Card B (Retrofit) communication interface board, part number 4,070,913, hardware revision V1.8A, designed to connect compatible photovoltaic inverters to the Fronius DATCOM / Solar Net communication and monitoring system.
The board transfers inverter operating data to compatible data acquisition devices, data loggers, and other DATCOM components. It acts as an interface between the inverter's internal network and the Fronius Solar Net communication bus.
It is intended for compatible inverters in the Fronius IG Plus and Fronius IG series, including models in the IG 15–60 family, such as the Fronius IG 60, subject to verification of the configuration and spare-part compatibility.
The board features two shielded RJ45 ports marked IN and OUT for daisy-chain connections. It also incorporates a switching power supply for compatible DATCOM components.
Official Fronius documentation confirms that COM-Cards connect inverters to the Solar Net network, feature two RS-422 interfaces, and provide galvanic isolation between the photovoltaic system and the communication network.

⚙️ Main Specifications

• Manufacturer: Fronius International GmbH
• Designation: COM-Card B / COM-Card Retrofit
• Part number: 4,070,913
• Hardware revision: V1.8A
• System family: Fronius DATCOM / Solar Net
• Type: Plug-in electronic communication board
• Communication interface: RS-422
• External connectors: 2 shielded RJ45 ports
• Communication ports: IN / OUT
• Power supply: Integrated switching circuit
• Installation: Inside a compatible inverter
• Bracket: Integrated metal mounting bracket

🔧 Main Functions

• Connects the inverter to the Fronius Solar Net communication network.
• Transmits operating data to compatible DATCOM devices.
• Enables communication between multiple inverters connected to the same network.
• Connects to compatible data loggers and data acquisition systems.
• Supplies power to DATCOM components required by the system configuration.
• Provides galvanic isolation between the photovoltaic system and the communication network.

🔌 Purpose and Operation

The COM-Card B is installed in the inverter's designated slot and establishes the connection between the internal electronics and the Fronius communication system.
The two RJ45 ports allow network components to be connected:

• IN: Communication input from the preceding device.
• OUT: Communication output to the next device.
  This configuration allows multiple devices to be connected in a daisy chain using data cables and terminations that comply with the manufacturer's instructions.
  The integrated switching power supply also provides power to compatible DATCOM components. According to Fronius documentation, COM-Cards from version 1.7 onward use a switching power supply compatible with different mains voltages.

🧩 Compatibility

The board is intended for inverters designed for the COM-Card and compatible with Fronius Solar Net / DATCOM.
Reference inverter series:

• Fronius IG Plus
• Fronius IG
• Fronius IG 60, belonging to the Fronius IG 15–60 family.
  Official Fronius documentation lists the IG and IG Plus families among those using the COM-Card function. Compatibility with the individual inverter must nevertheless be confirmed by comparing the spare-part code and equipment configuration.
  Important: Before purchasing, verify that part number 4,070,913 and revision V1.8A are compatible with the exact inverter model.

🔍 Component Identification

The following markings are legible on the label of the photographed board:

• 4,070,913
• 2038 100
• 112301 0343
• V1.8A R
• COM-CARDB
  The identifying part number is 4,070,913. This board is distinct from the previously described V2.0C version: the photographs show hardware revision V1.8A.

🛠️ Applications

• Repair of compatible Fronius photovoltaic inverters.
• Replacement of a defective COM-Card.
• Restoration of Solar Net / DATCOM communication.
• Maintenance of photovoltaic systems with earlier-generation Fronius inverters.
• Restoration of connections to compatible data acquisition and monitoring devices.

🛡️ Product Condition

Used and tested board, complete with the metal mounting bracket and connectors visible in the photographs.

📦 Package Contents

• 1 × Fronius COM-Card B Retrofit electronic board.
• Part number: 4,070,913.
• Hardware revision: V1.8A.
• Integrated metal mounting bracket.

🟢 Summary

Fronius COM-Card B Retrofit V1.8A communication interface board, part number 4,070,913, used to integrate compatible inverters from the Fronius IG Plus and Fronius IG series, including the Fronius IG 60, into the DATCOM / Solar Net monitoring system.
Featuring an RS-422 interface, IN/OUT RJ45 ports, and an integrated switching power supply, it is a spare part for maintenance and communication restoration, subject to verification of compatibility with the inverter.
Safety Warning: The board may be powered by circuits connected to mains voltage. Installation and replacement must be performed by qualified personnel, with the inverter disconnected from the power supply and in accordance with the manufacturer's instructions.