HIRSCHMANN MM20-M4M4T1T1SAHH Hybrid Fast Ethernet Media Module

HIRSCHMANN MM20-M4M4T1T1SAHH (order code: MM20-M4M4T1T1SAHH…) is a hot-swappable hybrid Fast Ethernet Media Module designed for Hirschmann’s modular MICE (Modular Industrial Communication Equipment) Switch family (MS20 and MS30 series).

By combining 2 Multimode ST fiber optic ports and 2 RJ45 copper ports in a single unit, this module provides a cost-effective, space-saving hybrid solution for industrial control cabinets requiring both local copper connections and noise-immune fiber links.

Product Overview

Hirschmann MM20-M4M4T1T1SAHH is a hybrid 4-port Fast Ethernet media module featuring 2 x ST multimode optical fiber ports and 2 x RJ45 copper ports for MS20/30 modular switches. Designed for standard industrial environments, it enables direct local equipment wiring alongside long-distance, noise-free optical uplink connections—all within a single hot-swappable slot without interrupting active backplane communications.

Technical Parameter List

Product Features & Core Advantages

Hybrid Port Versatility: Combines local twisted-pair RJ45 drops and ST fiber optics into a single module, saving physical slot space on the switch backplane.

ST Bayonet Connectors: Secure, twist-lock ST optical connectors prevent accidental disconnects in heavy-vibration machinery environments.

Complete Optical Isolation: The 2 multimode ST fiber ports eliminate ground potential loops and electromagnetic noise over extended cable runs.

Seamless Hot-Swapping: Plugs into active MS20 or MS30 basic switch backplanes without interrupting communications on neighboring modules.

Auto-MDI/MDI-X & Auto-Speed Sensing: The RJ45 copper ports automatically adjust to 10/100 Mbps line speeds and eliminate the need for crossover cables.

Model Classification

Within the Hirschmann MICE MM20/MM30 series, media modules are categorized by their port mix, fiber connectors, and environmental ratings:

Environmental Tolerance Conditions

Operating Temperature Range: $0^\circ\text{C}$ to $+60^\circ\text{C}$ (Standard industrial tier).

Storage Temperature Range: $-40^\circ\text{C}$ to $+70^\circ\text{C}$.

Relative Humidity: 10% to 95% (Non-condensing).

Vibration Resistance: Compliant with IEC 60068-2-6.

Shock Resistance: Rated up to 15g shock (11 ms duration per IEC 60068-2-27).

EMC Standards: EN 61000-4-2 (ESD), EN 61000-4-3 (Radiated Immunity), and EN 61000-4-4 (Burst).

Installation Method

ESD Grounding: Wear an anti-static wrist strap connected to cabinet earth before handling the unit.

Backplane Insertion:

Align the guide rails of the MM20-M4M4T1T1SAHH with an available slot on the host MS20 or MS30 basic switch.

Slide the module firmly into the slot until the backplane connector locks in place.

Mechanical Fixing: Hand-tighten top and bottom captive thumbscrews on the faceplate to ground the chassis and secure the board.

Cabling Connections:

ST Optical Fiber: Push and twist the ST bayonet fiber connectors onto the optical ports (ensure Tx connects to Rx on the remote side).

RJ45 Copper: Plug standard shielded Cat5e/Cat6 patch cables into the copper jacks until the release tab snaps shut.

Operating Instructions

Hot-Swap Maintenance: Modules can be inserted, swapped, or serviced while the parent switch is powered on without causing software errors or requiring a system reboot.

LED Status Indicators:

Link/Data LED (Solid Green): Valid physical connection established.

Blinking Green/Yellow: Active network packet processing.

LED Off: Cable disconnected, improper optical Tx/Rx alignment, or cable distance limit exceeded.

Port Care & Dust Covers: Keep rubber dust caps on unpopulated ST fiber sockets and plastic covers on unused RJ45 ports to prevent dust accumulation inside optical lenses and copper contacts.