General
Number of serial ports	8

The Moxa OPT8-M9+ is an 8-port connection box for serial RS-232 devices, enabling a structured and organized connection between multiple serial end devices and a serial expansion card. It is part of the OPT series from Moxa and is particularly designed for industrial environments where clear and reliable interface connections are required. The box provides eight independent serial ports at the device interface, connecting them via an integrated cable to the expansion card in the host system.

Applications
The connection box is designed for use in industrial plants, automation systems, and other environments where multiple serial devices such as sensors, controls, or measuring instruments must be connected to a central system. Its modular design allows flexible integration into existing infrastructures, with serial devices connected via standardized interfaces. The use of DB9 sockets ensures compatibility with a wide range of legacy and modern serial devices.

Functions and Equipment in DetailEach of the eight ports at the device interface is equipped with an LED indicator for transmit (TxD) and receive data (RxD), facilitating diagnostics of data transmission during operation. The indicator enables visual monitoring of communication activity without requiring additional measuring instruments. The included connection cable is 1.5 m long and designed for connection to the serial expansion card. The cable connection is made via a VHDCI 68 connector, which connects to the expansion card.

Technology Explained SimplyThe OPT8-M9+ operates with the RS-232 interface, a widely used standard for serial data transmission employed in many industrial and technical devices. The box supports baud rates from 50 bps to 921.6 kbps, with the exact bandwidth varying depending on the model. The connection is made via a DB9 connector at the device interface, enabling direct connection to standard and industrial-grade devices. The connection to the expansion card is made via a VHDCI 68 connector, designed for use with corresponding serial cards in the host system.

Compatibility and AccessoriesThe connection box is specifically designed for use with serial expansion cards featuring a VHDCI 68 connector. Compatibility is limited to the Moxa OPT series model range, with the OPT8-M9+ specifically designed for VHDCI 68 expansion cards. The connection is made via the included 1.5 m cable, which establishes the electrical connection between the box and the expansion card. The box itself does not feature integrated surge protection, as this is only specified for other models in the series (e.g. OPT 8S).

Mounting and InstallationMounting is typically done directly at the workstation or near the serial devices. Due to its compact dimensions (90 × 111 × 27.5 mm), the box can be easily integrated into enclosures or on work surfaces. The LED indicators simplify commissioning, as they provide immediate visual feedback on data transmission.

Operational AdvantagesThe OPT8-M9+ offers clear and organized structuring of serial connections, simplifying maintenance and troubleshooting during operation. The integrated LED indicators enable quick diagnosis of communication issues without requiring additional measuring instruments. The use of a standardized DB9 connector ensures high compatibility with existing devices. The 1.5 m long connection cable allows flexible positioning of the box relative to the expansion card without impairing signal quality.