Model 276A Optoverter - 2 Wire, RS-485
to Fiber Optic Line Driver/Converter Reference
1.0 General Description
The Model 276A Optoverter(, 2 wire RS-485 to Fiber Optic Line Driver/Converter,
provides the capability of extending the distance of an RS-485 network
to 6600 feet. At the same time it provides the inherent advantages of
transmission over fiber optic cable, immunity to interference, safety,
secure communications, etc.
2.1 Electrical: Half duplex RS-485, 2 wire
2.2 Fiber Interface: Optimized for 62.5/125 micron fiber cable
2.3 Wavelength: 850nm
2.4 Speed: 0-1.0 MHz
2.5 Power Budget: with 62.5/125 micron fiber 12dB
Fiber - 2Km (distances could exceed 2Km depending on fiber loss.)
RS-485 - per RS-485 specification
2.7 Connectors: Fiber = ST, RS-485 = DB-25 Female
2.8 Power: 115 VAC/60 Hz (220 VAC/50 Hz optional)
2.9 Size: 3.5" L x 2" W x .875" H
2.10 Environment: 0° to 50° C, 5 to 95% RH (no condensation)
The RS-485 connector to the Model 276A allows for half duplex operation
through a DB-25 female connector. Refer to the following chart for pin
The fiber optic port has been optimized for operation with 62.5/125 micron
cable and comes equipped with ST type fiber optic connectors for the transmit
and receive fibers.
The Model 276A can be connected to any RS-485 device running at speeds
up to 1 MHz. To connect the units, the connections 'Data In' are connected
to the 2 wire data from the RS-485 equipment and the 'Data Out' provides
a signal to the receive data pins of the RS-485 equipment. To connect
the 276A to another 276A the fiber connector marked T should be connected
to the far end fiber connector marked R, and the local R to the far end
The Model 276A is powered by a small DC power adapter that supplies reduced
DC voltage. In addition, power can be applied to the Model 276A by using
pin 9 on the DB25 female connector and pin 7 as the ground connection.
When using this pin, the input voltage should be +12VDC.
If any assistance is required call Bomara Associates at (800)-5BOMARA
Technical Support E-Mail: firstname.lastname@example.org
or use our Online Contact Form
Document No. 0315-0306
Telebyte warrants the equipment to be free from defects
in material and workmanship, under normal and proper use and in its unmodified
condition, for 12 months, starting on the date it is delivered for use.
TELEBYTE's sole obligation under this warranty shall be to furnish parts
and labor for the repair or replacement of products found by TELEBYTE
to be defective in material or workmanship during the warranty period.
Warranty repairs will be performed at the point of manufacture. Equipment
approved for return for warranty service shall be returned F.O.B. TELEBYTE
factory and will be redelivered by TELEBYTE freight prepaid, except for
non- continental U.S.A. locations. These deliveries will be sent COD freight
and import/export charges.
THE ABOVE WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED
OR IMPLIED, STATUTORY OR OTHERWISE, INCLUDING ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TELEBYTE SHALL NOT
BE LIABLE FOR ANY DAMAGES SUSTAINED BY RESELLER OR ANY OTHER PARTY ARISING
FROM OR RELATING TO ANY EQUIPMENT FAILURE, INCLUDING, BUT NOT LIMITED
TO CONSEQUENTIAL DAMAGES NOR SHALL TELEBYTE HAVE ANY LIABILITY FOR DELAYS
IN REPLACEMENT OR REPAIR OF EQUIPMENT.
Out of warranty equipment may be returned to the Greenlawn, NY customer
service facility prepaid as described above. Return shipping charges will
be billed to the customer. The repaired unit will have a 90 day warranty.
In those cases where "NO TROUBLE" is found, a reduced charge
will be billed to cover handling, testing and packaging.