General
Wavelength	1300 nm
Typical range	4 km
Link budget	12 dB
Dispersion penalty	3 dB
Air humidity	5–95 % nicht kondensierend

The Moxa IMC-21A-M-ST-T is an industrial media converter that enables a reliable connection between 10/100BaseT(X) Ethernet networks and 100BaseFX fiber optic links. It serves as a bridge between copper and fiber optic cables in industrial networks, where high electromagnetic immunity, mechanical robustness, and operation under extreme environmental conditions are required. The device is specifically designed for use in production facilities, power supply, transportation technology, and other industrial environments, where stable and maintenance-friendly network communication is essential.

Applications

The IMC-21A-M-ST-T is suitable for applications requiring network range extension via fiber optic, for example in factories with distributed machine control, in process automation, or in connecting sites over longer distances. The multi-mode fiber optic with ST connector enables a typical range of up to 4 km, which is sufficient for many industrial installations. The -T model designation indicates the extended operating temperature range, enabling use in climatically demanding environments such as outdoor areas, cooling plants, or regions with extreme temperatures.

Functions and Equipment in Detail

The device features an RJ45 interface for connection to Ethernet devices and a fiber optic interface with ST connector for the 100BaseFX connection. The RJ45 interface supports Auto-Negotiation and Auto-MDI/MDI-X, enabling automatic configuration of the connection without requiring additional switching. For manual control of network settings, DIP switches are available, allowing speed and duplex mode (half- or full-duplex) to be set manually. This provides flexibility when integrating into existing networks with specific requirements.

Technology Explained Simply

The media converter converts the electrical signals of the Ethernet network into optical signals for fiber optic transmission and vice versa. The wavelength is 1300 nm for multi-mode fibers, enabling efficient transmission over the specified range. The TX power is between -10 and -20 dBm, sufficient for stable signal transmission over multi-mode fibers. The RX reception range of -3 to -32 dBm ensures that weak signals are still received correctly. The link budget of 12 dB for multi-mode fibers is sufficient to compensate for losses caused by cables, connections, and other components in the network. The Link Fault Pass-Through (LFPT) function allows network faults to be quickly localized by forwarding the fault status to the connected device, simplifying maintenance and troubleshooting.

Compatibility and Accessories

The converter is compatible with standard 10/100BaseT(X) Ethernet devices and multi-mode fiber optic cables with ST connectors. Fiber types OM1 (multi-mode) and G.652 (single-mode) are supported, with the recommendation to use an attenuator for single-mode connections to ensure signal quality. The connection is made via a terminal block for power supply, providing a secure and robust connection option. Power supply is via 12 to 48 VDC, with integrated overcurrent and reverse polarity protection to prevent damage to the device.

Mounting and Installation

The device is mounted on a DIN rail, enabling simple and standardized installation in enclosures. The metal housing provides mechanical protection and acts as electromagnetic shielding. The protection rating IP30 protects against solid foreign objects with a diameter greater than 2.5 mm, offering some protection against dust and contact, but not against water or splashing water. Mounting is tool-free, and the DIN rail is standard in typical enclosures.

Operational Advantages

The IMC-21A-M-ST-T is characterized by high operational reliability, supported by its wide operating temperature range of -40 to 75 °C, making it suitable for use in extreme environments. Integrated protection functions such as overcurrent and reverse polarity protection increase reliability. The MTBF (Mean Time Between Failures) is 353,000 hours according to MIL-HDBK-217F, indicating a long service life and low failure probability. The 5-year manufacturer's warranty underscores the quality and reliability of the product.

Scope of Delivery

The scope of delivery includes the IMC-21A-M-ST-T media converter, a quick start guide, and a warranty card. These components are included in the delivery and serve for installation and maintenance of the device.