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Version 

3

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Brief instruction

Brief instruction FLEXtra® FO 650

Application and functional description

The FLEXtra® FO is primarily a normal PROFIBUS 
repeater with the capability of expansion by 2 (with 
FO-2) or 5 (with FO-5) additional optical MPI/PROFIBUS 
segments.
It translates an electrical MPI/PROFBUS interface into an 
optical MPI/PROFIBUS interface and vice-versa.
It regenerates the edge steepness, level and duty cycle 
of signals. In addition it brings the advantages of 
optical signal transfer to the MPI/PROFIBUS network.

The Flextra FO are available in 3 different variants:
(Suitable for POF resp. PCF

2)

)

FLEXtra® FO 650-2:

Connector type BFOC

1)

 resp. ST, 650 nm 

700-996-2AA01

Connector type SMA, 650 nm 

 

700-996-2BA01

Connector type Versatile Link

3)

 resp. HP, 650 nm  700-996-2CA01

FLEXtra® FO 650-5:

Connector type BFOC

1)

 resp. ST, 650 nm 

700-996-5AA01

Connector type SMA, 650 nm 

 

700-996-5BA01

Connector type Versatile Link

3) 

resp. HP, 650 nm

 

700-996-5CA01

1. 

The FLEXtra® FO is suitable for mounting on a DIN 

rail. It is engaged as shown in the picture.

2. 

A DIP switch is installed for deactivating the repeat 

function on the individual ports. 
Furthermore, the DIP switch DIP 4 (FO-2) or DIP 7 
(FO-5), can be used as the ON / OFF switch for all 
segments.

With optical ports, switching off a port does not mean 
that the send diode (Tx) is switched off, rather that the 
port can no longer receive data at the Rx input. Hence 
the repeater function of the port is deactivated.

Brief instruction FLEXtra® FO 650

3. 

If port X1 of the FLEXtra® FO is at the start or end of 

a segment then termination on the POFIBUS connector 
must be switched on (ON).

If port X1 of the FLEXtra® FO is in the middle of a 
segment then termination on the PROFIBUS connector 
must be switched off (OFF). 

The PROFIBUS is connected to the FLEXtra® FO via the 
SUB-D female connector. Connection of the optical seg-
ment is, dependent on type, via BFOC

1)

 resp. ST, SMA 

or Versatile Link

3)

 resp. HP connectors. 

Termination is not required for the optical ports.

ON
OFF

4. 

Connect the optical fi bre cables to ports X2 – X5 of 

the device. The following fi bres can be used:

• 

Polymeric Optical Fibre (POF):

• 

980/1000 μm

• 

Wavelength: 650 mm

• Loss approx 160 db/km

• 

Polymer Cladded Fibre (PCF

2)

 resp. HCS):

• 

200/230 μm

• 

Wavelength: 650 mm

• Loss approx 10 db/km

Note: 

For the assembly are separate connectors, and 

special assembly tools according to the required plug 
connection technology required.
The information on installation to a POF type please refer 
the steps A to C (see reverse side).
You may obtain the necessary fi ber cable completely pre-
assembled from your FO supplier.

Connect the optical ports via a CROSS-OVER connec-

tion i.e. TxD fi bre of the other end to the RxD connector 

of the FLEXtra® FO.

Connect RxD fi bre of the other end to the TxD connec-

tor of the FLEXtra® FO.

Opt

opus

650

PLC

subnetwork 1 up to 32 stations

subnetwork 2 up to 32 stations

PROFIBUS slave

PROFIBUS slave

“R” ON

“R” OFF

“R” ON

“R” ON

“R” OFF

“R” ON

PC

Note: 

PROFIBUS connectors are not included. See also: www.profi busstecker.de

Connector plugs for the optical connection are not included. These are available from your FO supplier.

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