I-7520 - RS-232 to RS-485 isolated converter

Industrial Isolated RS-232 to RS-485 Converter. 

The I-7520 is an advanced isolated RS-232 to RS-485 converter that enables reliable and stable communication between devices in industrial automation, SCADA systems, and smart buildings. This device eliminates the limitations of the RS-232 standard, allowing communication over distances up to 1200 m and enabling multiple device connections on an RS-485 network.

Built for real-world RS-485 field networks, the I-7520 works with a differential 2-wire half-duplex RS-485 bus and uses an internal Self-Tuner to automatically detect the baud rate and data format while precisely controlling the RS-485 transmission direction. This helps reduce integration time in mixed environments where different devices may operate at different speeds, while maintaining predictable serial communication for controllers, PLCs, HMIs, and metering equipment.

With 3000 VDC galvanic isolation, the I-7520 effectively protects systems from electrical surges and interference, ensuring secure communication even in demanding industrial environments. Automatic transmission direction control eliminates the need for manual configuration, making this converter exceptionally user-friendly. The device supports a wide input voltage range (10-30 VDC), ensuring compatibility with various industrial power systems.

In the I-7520 design, the isolation barrier is located on the RS-232 interface side, helping protect the host PC/PLC from transients coming from the RS-485 field wiring. This architecture is especially valuable in long cable runs, distributed automation cabinets, and installations where ground potential differences and EMI are common. Typical power demand is low (approx. 0.05 A at 24 V, max.), which supports compact control cabinet designs and stable operation in 24 VDC infrastructures.

The I-7520 is widely used in SCADA, Modbus RTU, energy management, and industrial applications where long-distance communication and resistance to electromagnetic interference are required. Its robust construction and ease of DIN rail mounting make it an ideal solution for installations requiring reliable RS-232 to RS-485 conversion.

For scalable RS-485 deployments, the converter supports up to 256 modules on a single RS-485 network without a repeater, and up to 2048 modules with repeaters (application-dependent). If your installation exceeds typical limits (e.g., very long runs or high node counts), adding repeaters helps preserve signal integrity and keeps the network stable under industrial noise conditions.

Key Features and Benefits

Product features

• 3000 VDC Isolation – protects systems from surges and potential differences, enhancing transmission security.
• Automatic Transmission Direction Control – built-in Self-Tuner mechanism eliminates the need for manual configuration.
• Wide Power Supply Range – 10-30 VDC input allows flexible deployment in various environments.
• Long Transmission Range – up to 1200 m at 9.6 kbps and 400 m at 115.2 kbps.
• Multiple Baud Rate Support – from 300 to 115200 bps, enabling integration with diverse automation systems.
• SCADA and PLC Compatibility – ideal for industrial applications.
• DIN Rail Mounting – easy and stable installation in control cabinets.
• Interference-Resistant Housing – made of UL94-V0 flame-retardant material.

The I-7520 is a reliable solution for systems requiring stable and long-distance communication. With high isolation, automatic transmission control, and wide baud rate support, this device is a perfect choice for professional industrial installations and monitoring systems.

Technical Specifications

Technical specification

The I-7520 is an isolated RS-232 to RS-485 converter that ensures reliable data transmission over long distances and effective protection against electromagnetic interference. It supports a wide range of baud rates and automatic transmission direction control, making it ideal for industrial automation.

RS-485 wiring is based on Data+ and Data- differential lines plus power terminals (+VS and GND) for the 10–30 VDC supply, while the RS-232 side uses the standard DB9 signal mapping (Host RXD/TXD/GND). This clear separation of field bus wiring and host serial wiring helps avoid common commissioning issues such as swapped polarity, ground reference mistakes, and unstable communication on long cable runs.

With its robust construction and flame-retardant UL94-V0 housing, the I-7520 is ideal for demanding industrial environments, ensuring reliability and long service life.

FAQ – I-7520

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