General
Number of serial ports	8

The Moxa Connection Box Opt8-M9 is an 8-port connection box for serial RS-232 connections, used in industrial applications with high port density. It serves as a consolidation element between serial end devices and Moxa multi-port serial cards, enabling structured and clear cabling. The device features eight serial interfaces, each equipped with a DB9 male connector, providing a compact solution for connecting multiple devices to a central serial interface. The connection box is designed for use in industrial environments where reliable and maintenance-friendly infrastructure is required.

Applications

The Opt8-M9 is particularly suitable for applications where multiple serial devices such as sensors, measuring instruments, controls, or industrial peripherals must be connected to a central system. Typical use cases include automation systems, process control technology, building automation, or industrial communication networks requiring a high number of RS-232 ports. The compact design and clear organization of connections facilitate installation and maintenance in tight enclosures or on mounting plates.

Functions and Equipment in Detail

Each of the eight serial ports is equipped with separate LED indicators for data transmission (TxD/RxD), allowing visual monitoring of each connection. The LEDs indicate whether data is being sent (TxD) or received (RxD), which is helpful for troubleshooting and diagnosing connection issues. The connection box features a DB62 male connector for connection to Moxa multi-port serial cards, establishing a direct and stable interface to the host system. The connection is made via a 1.5 m cable, which, depending on the model combination, connects either DB62 to DB62 or VHDCI 68 to DB62.

Technology Explained Simply

The RS-232 interface is a standard for serial communication still widely used in many industrial devices and older systems. The Opt8-M9 supports baud rates from 50 bps to 921.6 kbps, enabling flexible adaptation to different devices and transmission speeds. The use of DB9 connectors is common in industry due to their robustness and ease of connection. The connection box is designed to transmit the electrical signals of the serial interface without modifying or processing the data — it functions purely as a mechanical and electrical transition.

Compatibility and Accessories

The Opt8-M9 is specifically designed for use with Moxa multi-port serial cards featuring a DB62 connector. The connection is made via the included 1.5 m cable linking the connection box to the serial card. The box does not feature surge protection, unlike other models in the Opt8 series (e.g. OPT 8S). For applications with increased surge risk, other models in the series are more suitable. The connection box does not include a power supply or power source, as it does not perform active signal processing.

Mounting and Installation

The Opt8-M9 can be installed in enclosures or on mounting plates. Its compact dimensions of 90 × 111 × 27.5 mm allow space-saving installation. Installation involves connecting the connection box to the Moxa serial card using the included cable. Serial end devices are connected to the DB9 connectors on the box. The LED indicators enable visual verification of connections during installation.

Operational Advantages

The Opt8-M9 provides a clear and structured cabling solution, simplifying maintenance and diagnosis of serial connections. The LED indicators allow quick identification of activity on individual ports. The use of a standardized DB9 connector ensures compatibility with a wide range of devices. The robust construction and stable housing design ensure reliable operation in industrial environments.

Scope of Delivery

The scope of delivery includes an 8-port RS-232 connection box (model Opt8-M9) and a 1.5 m connection cable for connecting to Moxa multi-port serial cards.