Phoenix FL MC 1000 SC (ST) Fiber Optic Converter

Phoenix Contact FL MC 1000 Series Industrial Ethernet Fiber Media Converter: Comprehensive Technical Analysis and Application Guide

Introduction

Ethernet has become the mainstream communication protocol in modern industrial automation, process control, traffic monitoring, and security systems. However, standard copper cables (twisted pair cables) have inherent limitations in terms of transmission distance (up to 100 meters), electromagnetic interference (EMI) resistance, and electrical isolation. To address these challenges, fiber optic communication technology has been widely introduced into industrial networks. As a global leader in industrial connectivity and communication technology, Phoenix Contact has launched the FL MC 1000 series basic media converter, aimed at achieving seamless conversion from 10/100Base Tx electrical interface to 100Base FX optical interface at an economical cost and reliable performance, providing long-distance, high immunity data transmission solutions for industrial sites.

This article will provide a comprehensive and in-depth technical analysis of the FL MC 1000 series media converter, covering its core features, detailed technical specifications, installation and configuration methods, typical application scenarios, and accessory selection recommendations, providing an authoritative reference guide for system integrators and on-site engineers.

Product Overview

The FL MC 1000 series is a basic media converter designed by Phoenix Contact specifically for general industrial environments. The main function of this series of products is to convert standard 10/100Mbps twisted pair Ethernet signals into 100Mbps fiber optic signals (compliant with the 100Base FX standard). It supports two common types of fiber optic connectors:

FL MC 1000 SC (Order Number: 2891320): Equipped with SC duplex connector, using 1310nm wavelength, suitable for multimode fiber.

FL MC 1000 ST (Order Number: 2891321): Equipped with ST connector, also using 1310nm wavelength, multimode fiber.

These two products are completely identical in terms of electrical performance and functionality, with only the fiber optic physical interface being different. Users can flexibly choose based on the existing fiber optic jumpers or patch panel interface types on site. Its compact metal casing (28 x 110 x 70 mm) is designed for DIN rail installation and can be easily integrated into standard NS 35 control cabinets, meeting IP20 protection levels and suitable for dry and clean industrial sites.

Core features and functional advantages

3.1 10/100Base Tx to Fiber Optic Conversion

The core task of the FL MC 1000 series is to achieve media conversion. It converts electrical signals from RJ45 ports (supporting 10Mbps or 100Mbps adaptive) into optical signals that comply with the 100Base FX standard, and transmits them through multimode fiber. The direct benefits of this conversion include:

The transmission distance has been significantly extended: the maximum transmission distance of copper Ethernet is only 100 meters, while through the FL MC 1000 series, using different specifications of multimode fiber, the transmission distance can be extended to 2 kilometers to 9.6 kilometers, completely breaking through the distance limit.

Extremely strong anti electromagnetic interference capability: Optical fibers themselves are non-conductive and not affected by transient overvoltage caused by electromagnetic fields, radio frequency interference (RFI), or lightning strikes. This makes the FL MC 1000 series very suitable for deployment near high interference sources such as frequency converters, high-power motors, and welding equipment.

Electrical isolation: Fiber optic provides complete electrical isolation, eliminating the problem of ground potential difference, avoiding grounding loops, and improving the safety and stability of the system.

3.2 Auto Crossing function

In traditional Ethernet connections, cross cables are required between devices of the same type (such as two computers), while straight cables are used between devices of different types (such as computers and switches). The RJ45 port of FL MC 1000 series integrates automatic MDI/MDIX function, namely "automatic crossover". This function can automatically detect the type of cable connected and adjust the internal signal pin allocation accordingly. Therefore, regardless of whether the user is using a straight through network cable or a crossover network cable, the device can establish a link normally. This feature greatly simplifies on-site wiring work and reduces debugging failures caused by incorrect cable types, especially suitable for maintenance scenarios without professional network cabling personnel.

3.3 Link Fault Pass Through (LFPT)

Link fault direct access is an important diagnostic function that helps improve the maintainability of the entire network. The FL MC 1000 series enables or disables this feature through the DIP switch at the bottom (position 1).

Working principle: When LFPT is enabled, if any port (RJ45 or fiber optic) of the media converter detects a link loss (such as fiber optic being cut off or the other end device being powered off), the converter will forcibly shut down the other port. In this way, the signal lost in the link can propagate directly to the terminal devices at both ends (such as PLCs or switches).

Value: Without LFPT, when the fiber optic link is interrupted, the RJ45 end device may still consider the link to be normal (because the directly connected electrical port is still active), causing upper layer applications to be unable to timely detect the fault, resulting in data loss or response delay. After enabling LFPT, both devices on both ends can immediately detect link interruptions, triggering alarms or redundant switching mechanisms. The manual specifically states that the LFPT function should only be enabled when two media converters are used in series to ensure the correct propagation of fault signals.

3.4 Rich LED status indicator lights

The front panel of the device provides a clear array of LED indicator lights for quick on-site diagnosis:

US (power supply): Green constant light indicates that the power supply voltage is within the allowable range; Turning off indicates that the voltage is too low.

LNK/ACT (Link/Activity): Green constant light indicates that the electrical interface link has been established; Green flashing indicates that data is being transmitted (it may appear as a constant light when the data rate is high).

10/100 (speed): Orange constant light indicates that the RJ45 port is operating at 100Mbps; Extinguishing indicates working at 10Mbps.

Fiber port status: Although there is no independent LED, the fiber link status can be indirectly determined through the combination of LFPT and LNK/ACT.

3.5 Flexible DIP switch configuration

There is a 7-bit DIP switch at the bottom of the device, with the first 4 bits used to configure key operating parameters:

DIP Position Function Description

1 Link Fault Direct (LFPT) ON Global Fault: Either port failure, both ends disabled

OFF local fault: only interrupts the fault segment (recommended for startup or single link)

2 Self negotiation/forced mode OFF Self negotiation mode (default, automatically negotiating rate and duplex with the other end)

ON forced mode (requires manual setting with DIP 3 and 4)

3 Transmission rate (in forced mode) OFF 100 Mbps

ON 10 Mbps

4 Duplex Mode (Forced Mode) OFF Full Duplex

ON half duplex

Note: DIP bits 5, 6, and 7 are reserved for future expansion.

This configuration system enables the FL MC 1000 series to seamlessly integrate into standard self negotiating networks, as well as enforce specified port operating modes when required to interface with old or special devices, ensuring compatibility.

3.6 Security Frame Support

The RJ45 port design is compatible with Phoenix Contact's FL PLUG GUARD series safety locks. This attachment can physically lock Ethernet cables to prevent unauthorized plugging or unauthorized device access, enhancing the physical security of industrial networks in open or semi open environments.

Detailed technical specifications

4.1 Power Supply

The FL MC 1000 series uses pluggable screw terminal blocks for power supply and supports a wide range of DC inputs:

Nominal voltage: 24 V DC or 48 V DC

Allowable voltage range: 12 V DC... 57 V DC

Typical current consumption: 73 mA @ 24 V DC

Allowable ripple: 3.6 Vpp (within voltage range)

Surge current: 8 A at 48 V DC (continuous for 1.8 ms)

Polarity reversal protection: built-in

Test voltage withstand: 500 V AC (1 minute)

The power terminal can be connected to 0.2 2.5 mm ² (24... 12 AWG) wire, recommended PE grounding wire is 2.5 mm ². The required tightening torque is 0.5 .. 0.6 Nm。

Important safety reminder: The device is designed for SELV (Safety Extra Low Voltage) and PELV (Protection Extra Low Voltage) circuits and must comply with IEC 61140/EN 61140 standards. When the device is mounted on a grounded DIN rail, a grounding connection is automatically established, but it is recommended to use grounding terminals to ensure low impedance grounding.

4.2 Ethernet interface (RJ45)

Number of interfaces: 1

Connector type: RJ45 female socket

Transmission medium: twisted pair, conductor cross-section 0.14 mm ²... 0.22 mm ², characteristic impedance 100 Ω

Transmission speed: 10 Mbps or 100 Mbps (auto negotiated or forced)

Maximum network segment length: 100 meters

MDI/MDIX switching: automatic

4.3 Fiber optic interface (SC or ST)

Number of interfaces: 1 (including both sending and receiving channels)

Connector type: SC duplex (FL MC 1000 SC) or ST (FL MC 1000 ST)

Wavelength: 1310 nm

Transmission speed: 100 Mbps (fixed, due to 100Base FX)

Fiber types: multimode glass fiber (62.5/125 μ m or 50/125 μ m), and HCS (hard clad quartz) fiber

Typical transmission distance (depending on fiber quality):

Using 62.5/125 μ m, attenuation of 0.7 dB/km (F1000): 8 km

Using 62.5/125 μ m, attenuation of 2.6 dB/km (F600): 3.3 km

Using 50/125 μ m, attenuation of 0.7 dB/km (F1200): 9.6 km

Using 62.5/125 μ m, attenuation of 1.6 dB/km (F800): 5.3 km

Using 200/230 μ m HCS GI fiber (F-GK): 2 km

Operation warning: It is strictly prohibited to directly look at the emitting diode or use optical auxiliary tools to observe the fiber end face during work, as 1310nm infrared light is not visible but may damage the eyes. Additionally, do not remove the dust cap before connecting to prevent contamination of the optical components.

4.4 Environmental and Mechanical Specifications

Working temperature: 0 ° C... 60 ° C

Storage temperature: 0 ° C... 70 ° C

Relative humidity: 5% 95% (no condensation)

Working pressure: 66 kPa... 108 kPa (corresponding to a maximum altitude of 4850 meters)

Protection level: IP20

Protection category: Class 3 (VDE 0106/IEC 60536)

Vibration tolerance: Complies with IEC 60068-2-6, 10... 150 Hz, 5g

Impact resistance: Complies with IEC 60068-2-27, 30g, 11ms (during operation)

Free fall: compliant with IEC 60068-2-32, 1 meter

Electromagnetic compatibility: Complies with IEC 61000-6.2 (industrial environment immunity standard)

These specifications indicate that the FL MC 1000 series is capable of long-term stable operation in typical industrial control cabinet environments, withstanding common mechanical vibrations and electromagnetic interference.

Installation and Wiring Guide

5.1 DIN rail installation

Installation: Hang the module from top to bottom onto the NS 35 DIN rail, ensuring that the upper fixing claws hook onto the upper edge of the rail; Then push the module towards the installation surface until you hear a "click" sound, indicating it is tightened. After installation, check for firmness.

Disassembly: Use a suitable tool (such as a screwdriver) to insert the locking claw and pull it down; At the same time, pull the module out slightly and then lift it up to remove it.

End clamp: It is recommended to install universal end clamps (E/NS 35 N, order number 0800886) on both sides of the module to prevent the module from sliding on the guide rail.

5.2 Power Wiring

Use 0.2 Connect a 2.5 mm ² wire to the power terminal (note polarity:+24V and 0V).

It is recommended to connect the DIN rail to the protective earth (PE) through the grounding terminal, as the module housing is grounded through the rail.

The torque for tightening the screw is 0.5 .. 0.6 Nm。

5.3 Ethernet cable connection

Insert the standard RJ45 plug into the front panel port. Due to the support for automatic crossover, there is no need to worry about straight or crossover lines.

Gently pull the cable to confirm a secure connection.

5.4 Fiber optic cable connection

Cleaning: Before connecting, ensure that the fiber optic plug is clean, and specialized cleaning tools can be used.

Alignment: Align the SC or ST connector correctly (pay attention to the positioning key) and insert it into the fiber port. For SC duplex connectors, it is usually necessary to ensure that the transmit (Tx) and receive (Rx) channels are cross connected with the other end (i.e. the local Tx is connected to the opposite Rx).

Fixed: For ST connectors, lock them by rotating a quarter turn after insertion; For SC connectors, simply push them in and the buckle will automatically lock.

Attention: Strictly follow the fiber manufacturer's minimum bending radius, maximum tensile force and other parameters to avoid signal attenuation or fiber breakage.

Detailed explanation of configuration and diagnosis

6.1 Basic configuration steps

Check the DIP switch settings (usually all bits are set to OFF by factory default).

Connect the power and observe if the US LED is constantly on.

Connect the RJ45 cable and observe whether the LNK/ACT and 10/100 LED are indicating the link and speed normally.

Connect the fiber optic cable and check if the other end device can establish a link. If the link is not working, try enabling DIP 1 (LFPT) or checking the fiber optic cross connection.

6.2 Typical Configuration Scenarios

Scenario 1: Connecting to a standard switch: Set DIP 2 to OFF (self negotiating), and the converter will automatically negotiate 100M full duplex with the switch. This is the most commonly used configuration.

Scenario 2: Connecting an old 10M device: Set DIP 2 to ON (forced mode), DIP 3 to ON (10Mbps), and DIP 4 to OFF (full duplex) or ON (half duplex) as needed.

Scenario 3: Enable Global Link Diagnosis: When using two FL MC 1000s connected back-to-back via fiber optic, set DIP 1 on both devices to ON. This way, any link failure on either side will cause both electrical ports to shut down simultaneously, notifying the terminal device.

6.3 Troubleshooting

Possible causes and solutions for the fault phenomenon

The US LED does not light up. The power supply is not connected or the voltage is too low. Check the power supply wiring and voltage (>12V is required)

LNK/ACT does not light up, RJ45 link not established. Check if the network cable is intact and if the other end device is powered on. Try replacing the crossover/straight line

Ensure Tx Rx cross connection due to fiber link failure, incorrect fiber connection or excessive attenuation; Clean the fiber optic end face; Check the bending radius; Calculate optical power budget

Check DIP 2-4 settings for low communication rate, duplex mismatch, or interference to ensure consistent self negotiation or forced settings at both ends; Check the quality of the network cable

Order information and attachments

7.1 Main products

Describe model, order number, packaging quantity

Fiber optic converter, SC connection, 1310nm, multimode FL MC 1000 SC 2891320 1

Fiber optic converter, ST connection, 1310nm, multimode FL MC 1000 ST 2891321 1

7.2 Recommended attachments

Describe model, order number, packaging quantity

Universal end clamp (for NS 35 rail) E/NS 35 N 0800886 50

CAT5 jumper, with various lengths ranging from 0.3m to 10m, FL CAT5 PATCH... see data manual 1

Security lock (RJ45 physical lock) FL PLUG GUARD... individual inquiry-

Typical application scenarios

8.1 Cross workshop/factory network connection

In large factories, the distance between different workshops may exceed 100 meters. The FL MC 1000 series can connect remote control cabinets or operation stations to a central switch via fiber optic cables for unified monitoring.

8.2 Strong electromagnetic interference environment

In places such as frequency converter rooms, large electric furnaces, and welding robot workstations, copper cables can induce a large amount of interference noise. Deploying the FL MC 1000 series to connect end devices via fiber optic can completely eliminate errors and packet loss caused by interference.

8.3 Outdoor monitoring and transportation system

IP cameras or traffic signal controllers along highways and railways typically require lightning protection and long-distance transmission. The non-metallic nature of optical fiber provides natural lightning protection, and the FL MC 1000 series can extend Ethernet signals to control centers several kilometers away.

8.4 Temporary or Mobile Systems

Due to its compact DIN rail installation and wide voltage input range, the FL MC 1000 series is also suitable for integration into test benches, mobile robots, or exhibition demonstration systems, facilitating quick deployment and disassembly.