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PSI-MOS-RS485W2/FO 1300 E Serial to Fiber Converter (Connect 2-wire RS485 devices to fiber optic cable)

psi mos rs485w2 fo1300e lg
  • Extend serial data up to 28 miles
  • Immune to EMI, RFI and transient surges
  • Point-to-point or star configuration
  • SC type fiber connectors
  • Terminal Block for 2-wire RS485 Connections

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The PSI-MOS-RS485W2/FO 1300 E can be used to convert RS485 2-wire devices to fiber optics. By transmitting serial data over optical fiber, these serial media converters provide an economical path to extend the reach of RS485 devices. All protocols with 10/11-bit UART data format and NRZ data coding are supported. This includes popular protocols such as:

  • S-BUS
  • DH-485, and more…

Long Distance Serial Data Transmission over Fiber

RS485 Serial transmission is commonly limited to 100 kbps over a distance of only 1200 meters (4000 feet). Using the FO 1300 E Serial to Fiber Converter you can extend your serial data transmission up to 27km (16.7 miles) over multimode fiber or 45km (28 miles) over single mode fiber. The result is that any two pieces of asynchronous serial equipment, located miles apart, can communicate at half duplex over fiber optic cable at rates up to 500 kbps.

EMI, RFI and Transient Surge Immunity

Another advantage of the FO 1300 E fiber optic transmission system is the electrically isolated connection of devices. Electromagnetic interference (EMI) is a common phenomenon in typical environments like industrial plants, warehouses and factory floors. This interference can cause corruption of data over RS485 or copper-based Ethernet links. Data transmitted over fiber optic cable however is completely immune to this type of noise, thus preventing the negative effects of voltage equalization currents and electromagnetic interference on the data cables. A Serial to Fiber Media Converter therefore enables you to inter-connect your serial devices over fiber ensuring optimal data transmission, increased availability of the system, and improved network design flexibility for point-to-point connections and star structures.

Flexible Fiber Optic Connections

The FO 1300 E operates at 1300 nm wavelength, using a separate LED emitter and photo-detector on SC type connectors. Almost any multimode or single mode glass fiber size can be used.

Power Budget Considerations

Calculating the power budget is critically important with planning the fiber optic link. The optical power budget is the amount of light required to transmit data successfully over distance through a fiber-optic connection. The amount of light energy available within the setup will dictate the length of the fiber optic cable run between serial media converters within the network. Optical power budgets are critical to help businesses avoid signal distortion.To learn how to calculate optical power budget read our technical note. Transmit and receive dBm can be found in the Hardware specifications.

Transmit each serial signal out over 10 fiber optic lines

Up to ten (10) Serial to Fiber Converters can be grouped together using the TBUS DIN Rail bus system for voltage and data. This allows the serial converter to operate as a star coupler, taking the serial data input signal and distributing it to all Fiber optic output ports.

High Quality Features and Support

The FO 1300 E are also equipped with comprehensive diagnostic functions to increase system availability, simplify start-up and permanently monitor the optical transmission quality. The integrated optical diagnostics allow permanent monitoring of the FO paths during installation and operation. The floating switch contact is activated when the signal level on the fiber optic paths reaches a critical level. This early alarm generation enables critical system states to be detected before they result in failure. These cost and time saving features, along with free worldwide technical support, make the FO 1300 E serial to fiber converter the smart choice for IT professionals.

  • Supply voltage and data signals routed through via DIN rail connectors
  • Connections can be plugged in using a COMBICON screw terminal block
  • Automatic data rate detection or fixed data rate setting via DIP switches
  • Redundant power supply possible by means of optional system power supply unit
  • High-quality electrical isolation between all interfaces (RS-485, fiber optic ports, power supply, DIN rail connector)
  • Approved for use in zone 2
  • Integrated optical diagnostics for continuous monitoring of fiber optic paths
  • Floating switch contact for leading alarm generation in relation to critical fiber optic paths
  • Suitable for data rates up to 500 kbps

Hardware Specs

PSI-MOS-RS485/FO 1300 E Technical Specifications

Ambient conditions
Ambient temperature (operation) -20 °C … 60 °C
Ambient temperature (storage/transport) -40 °C … 85 °C
Permissible humidity (operation) 30 % … 95 % (non-condensing)
Altitude 5000 m (For restrictions see manufacturer’s declaration)
Degree of protection IP20
Noise immunity EN 61000-6-2:2005
Standards and Regulations
Electromagnetic compatibility Conformance with EMC directive 89/336/EC
Type of test Vibration resistance in acc. with EN 60068-2-6/IEC 60068-2-6
Test result 5g, 10-150 Hz, 2.5 h, in XYZ direction
Type of test Shock in acc. with EN 60068-2-27/IEC 60068-2-27
Test result 15g, 11 ms period, half-sine shock pulse
Shock 15g in all directions in acc. with IEC 60068-2-27
Noise emission EN 55011
Noise immunity EN 61000-6-2:2005
Free from substances that could impair the application of coating according to P-VW 3.10.7 57 65 0 VW-AUDI-Seat central standard
Connection in acc. with standard CUL
Standards/regulations EN 61000-4-2
EN 61000-4-3
EN 61000-4-4
EN 61000-4-5
EN 61000-4-6
Vibration (operation) In acc. with IEC 60068-2-6: 5g, 150 Hz
Conformance CE-compliant
ATEX II 3 G Ex nA nC IIC T4 Gc X
UL, USA/Canada 508 listed
508 recognized
Optical interface FO
Number of FO ports 1
Wavelength 1300 nm
Transmission length incl. 3 dB system reserve 25 km (With F-G 50/125 0.7 dB/km at 1300 nm)
22 km (with F-G 62.5/125 0.8 dB/km at 1300 nm)
45 km (With F-E 9/125 0,4 dB/km at 1300 nm)
Transmission medium Multi-mode fiberglass
Single-mode fiberglass
Transmission protocol Protocol-transparent to the RS-485 interface
Connection method SC duplex
Bit distortion, input ± 35 % (permitted)
Bit distortion, output < 6.25 %
Electrical isolation VCC // RS-485
Test voltage data interface/power supply 1.5 kVrms (50 Hz, 1 min.)
Electromagnetic compatibility Conformance with EMC directive 89/336/EC
Noise emission EN 55011
Net weight 225.3 g
Housing material PA 6.6-FR
Color green
MTBF 484 Years (Telcordia standard, 25°C temperature, 21% operating cycle (5 days a week, 8 hours a day))
102 Years (Telcordia standard, 40°C temperature, 34.25% operating cycle (5 days a week, 12 hours a day))
Conformance CE-compliant
ATEX II 3 G Ex nA nC IIC T4 Gc X (Please follow the special installation instructions in the documentation!)
UL, USA/Canada 508 listed
508 recognized
Digital outputs
Output name Relay output
Output description Alarm output
Number of outputs 1
Maximum switching voltage 60 V DC
42 V AC
Limiting continuous current 1:00 AM
Power supply
Nominal supply voltage 24 V DC (With UL approval)
Supply voltage range 18 V DC … 32 V DC
Max. current consumption 90 mA
Typical current consumption 55 mA (24 V DC)
Connection method COMBICON plug-in screw terminal block
Typical current consumption 170 mA (According to UL Listed, 24 V DC)
110 mA (According to UL Recognized, 24 V DC)
Serial interface
Interface 1 RS-485 interface, 2-wire
Operating mode Semi-duplex
Connection method Pluggable screw connection
File format/coding UART (11/10 bit switchable; NRZ), slip-tolerant
Data direction switching Automatic control
Transmission medium Copper
Transmission length ≤ 1200 m (depending on the data rate, with shielded, twisted data cable)
Termination resistor 390 Ω
220 Ω
390 Ω (Can be connected)
Conductor cross section solid min. 0.2 mm²
Conductor cross section solid max. 2.5 mm²
Conductor cross section flexible min. 0.2 mm²
Conductor cross section flexible max. 2.5 mm²
Conductor cross section AWG min. 24
Conductor cross section AWG max. 14
Serial transmission speed 4.8/ 9.6/ 19.2/ 38.4/ 57.6/ 75/ 93.75/ 115.2/ 136/ 187.5/ 375/ 500 kbps
Width 35 mm
Height 99 mm
Depth 105 mm
PSI-MOS-RS485/FO 1300 E
Environmental Product Compliance
China RoHS Environmentally Friendly Use Period = 50
Reach and RoHS Compliant Reach and RoHS Compliant
cUL Listed
cULus Listed
UL Listed
cUL Recognized
cULus Recognized
UL Recognized
Commercial data
Packing unit 1
Weight per piece 230.1 g
Country of origin Germany
Warranty 1 Year
eCl@ss 4.0 27230207
eCl@ss 4.1 27230207
eCl@ss 5.0 27230207
eCl@ss 5.1 27230207
eCl@ss 6.0 27230207
eCl@ss 7.0 27230207
eCl@ss 8.0 19179290
eCl@ss 9.0 19179290
ETIM 2.0 EC001423
ETIM 3.0 EC001423
ETIM 4.0 EC001423
ETIM 5.0 EC000310
ETIM 6.0 EC000310
UNSPSC 6.01 30211506
UNSPSC 7.0901 39121008
UNSPSC 11 39121008
UNSPSC 12.01 39121008
UNSPSC 13.2 43222604

Application Diagrams

PSI-MOS-RS485/FO 1300 E Serial to Fiber Media Converter Applications
  • near heavy electrical equipment
  • in environments with electrical (EMI) or radio (RFI) interference
  • in environments with transient surges
  • in industrial plants, warehouses and factory floors
  • enabling asynchronous serial equipment to communicate at half duplex, with rates up to 500 kbps, over optical fiber
Point-to-point connections between serial devices over fiber
You can use two PSI-MOS-RS485W2/FO 1300 E Serial to Fiber Converters to easily convert a data link from copper cable to fiber optics.

RS485 Point to Point Network Diagram
Linear Networks
The PSI-MOS-RS485W2/FO 1300 E device can be used to network several RS-485 devices to form a linear structure. Devices are used in conjunction with DIN rail connectors along the line.

RS485 Linear Network Diagram
Star structures
You can network RS-485 2-wire devices within a star structure. Depending on the number of star lines required, several PSI-MOS-RS485W2/FO 1300 E Serial to Fiber Converters are connected to TBUS DIN Rail bus systems for voltage and data. This makes up to 10 fiber optic ports available. Cross-wiring for serial data and for the supply voltage is provided automatically by the DIN rail connector.

RS485 Star Network Diagram
Tree structures
Linear and star structures can be cascaded to create complex tree structures. The number of devices that can be cascaded is only limited by the timing response (timeout) of the bus system used due to the bit retiming of the PSI-MOS-RS485W2/FO 1300 E fiber optic converter.

Tree Network Diagram
Block Diagram
PSI-MOS-RS485/FO 1300 E Block Diagram

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