S.I. Tech, Inc.Model 2145 - Profibus - DP Fiber Optic Bit-Driver®

Operation Mode: RS485 - 2 wire
Profibus - DP
Input/Output Interface: EIA RS485A 2 wire
9600bps to 12Mbps
IEC 61158-2, Async, NRZ, 11 Bits
DB9 female
Transmission Line Interface: ST Connectors-standard (SMA option)
Optical Power (TR): See table 1
Receiver Sensitivity: See table 1
Operating Temperature: -25°C to +75°C
(-20°C to +60°C for SM)
Metal Enclosure: DIN Rail Mounting, 4.2" X 2.0" X 4.2"
(10.67 X 5.0 X 10.67 cm)
Weight: 1.25 lb (568 grams)
Input Power: 24VDC, 3 Watts, Terminal block
Electrical Isolation: 1500V
Conducted Emissions: EN55022 Class B
Mechanical: IP 40

View Complete Technical Data Sheet (PDF)


  • Meets PROFIBUS-DP specification. Tested & approved by PROFIBUS Lab
  • Modbus - RS485
  • Multimode and single mode, plastic or glass fiber
  • 2 port optical repeater, optical T-connector, optical to electrical converter [1 Port Optional]
  • 9600 bps to 12 Mbps - switch selectable
  • DIN rail mounting
  • Status indicators: Power, TxD, RxD, Invalid switch setting
  • Conformal coated boards

The Model 2145 Bit-Driver used in a PROFIBUS-DP application is a two optic port repeater with single TIA/EIA-485-A electrical port. The 2145 operates at rate 9600 baud to 12 Mbaud in linear bus topology. The 2145 can be used as an optical repeater between the fiber optic segments, an optical to electrical converter between an fiber optic segment and electrical station(s), or T-connector/repeater between two fiber optic segments and electrical station(s). The 2145 is transparent and does not evaluate the PROFIBUS data exchange.

Using fiber optics over the physical layer, the 2145 provides longer segment distances, electromagnetic noise immunity and ground potential difference independence in the linear bus topology. The 2145 optics can be optionally equipped with different characteristics.

The 2145 retimes the received optical signal and can link up to 32 fiber optic segments in series. The electrical port supports up to 31 stations.

The 2145 Termination switch can select an internal cable type-A termination. External terminations can derive power from the sub-D connector between pins 6 and 5.

The 2145 unit attaches to EN50022 (35mm DIN) mounting rail. Power is applied through screw terminals and data rate selection made through internal DIP switches.

UL Listed. Meets FCC requirements of Class A, Part 15 Computing Devices Standard.
Specifications subject to change without notice.

Contact Information: Phone: 630.761.3640 Fax: 630.761.3644 Email: sales@sitech-bitdriver.com
S.I. Tech, Bit-Driver®, and Fiber Cluster® are registered trademarks of S.I. Tech, Inc.
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