B&B Electronics FOSTC - Datasheet - Manual (Page 5)

FOSTC-0812-5/6
© 2002 by B&B Electronics. All rights reserved.
www.bb-elec.com [email protected] [email protected]
International Office: 707 Dayton Road PO Box 1040 Ottawa, IL 61350 USA 815-433-5100 Fax 433-5104
European Office: Westlink Commercial Park Oranmore Co. Galway Ireland +353 91 792444 Fax +353 91 792445
PRODU
CT I
NFO
RMATI
O
N
B&B E
LECTR
ON
ICS
Recommended Maximum FOSTCs
in a Fiber Ring Topology.
Baud Rate RS-232
Operation
RS-422/485
Operation
460.8 kbps N/A 2
230.4 kbps N/A 4
115.2 kbps 2 8
57.6 kbps 8 16
38.4 kbps 16 24
19.2 kbps
and lower 32 32
Specifications/Features
Transmission Line: Dual multimode optical cable
Point-to-Point Transmission: Asynchronous, half or full-duplex
Multi-Drop Transmission: Asynchronous, half duplex fiber ring
Interfaces: RS-232, RS-422, or RS-485
Connectors: DB25 female for serial connection, ST connectors for fiber
Dimensions: 4.3 x 2.3 x 0.95 in (11 x 5.9 x 2.5 cm)
Power Supply Connections: 2.5mm phone jack (Tip Positive) or DB25 pins 25(+) & 12(-)
Recommended Power Supply: B&B Model# 232PS3
All specifications given using 62.5/125µm glass multi-mode fiber.
Parameter Min. Typical Max. Conditions
Data Rates
(RS-232 Operation) 0 bps 115.2 kbps
Data Rates
(RS-422/485 Operation) 0 bps 500 kbps
Power Supply Voltage 10 VDC 12 VDC 14 VDC
Power Supply Current Draw 140 mA Full RS-485 Termination
Optic Wavelength 820 nm
Fiber TX Launch Power -17 dBm -13 dBm -10 dBm
Minimum Required Fiber Rx Power -25.4 dBm -24 dBm
Maximum Receiver Power -10 dBm
Coupled Power Budget 12.1 dB
Fiber Range 2.5 Miles
End to End Delay 2000 ns 2650 ns Point to Point RS-232 Operation
(See Notes 1 & 2)
End to End Delay 550 ns 1000 ns Point to Point RS-422/485 Operation
(See Notes 1 & 2)
End to End Skew 900 ns 1100 ns Point to Point RS-232 Operation
(See Note 3)
End to End Skew 50 ns 120 ns Point to Point RS-422/485 Operation
(See Note 3)
Maximum Total Fiber Ring Length 5 Miles (See Note 1)
Delay between Rx & Tx on a fiber ring 52 µs (See Note 4)
Note 1: For the total transmission time over long fibers, the time to
transverse the fiber must be considered if delay is an issue. Light takes
about 8.05 microseconds to travel over 1 mile of fiber.
Note 2: When operating in a ring configuration, each node in addition to
the two in the point-to-point specification adds an additional 100 to 200
nanoseconds of delay.
Note 3: When operating in a ring configuration, each node in addition to
the two in the point-to-point specification adds an additional 50 to 70
nanoseconds of skew.
Note 4: When operating in a ring configuration, each serial device must
wait at least this minimum time between receiving data from the ring and
transmitting back on to it.