OPGW - optical ground wire - for transmission lines 1

[power2020]

Hi Folks,
overhead line OPGW is meant for both earthing and communication..
My doubts
1) how is it constructed fot both?
2) how is optical signal transfer takes place and how many signals.
3) how do we differentiate signals for protection & communication.

experts edvice please..
thanks,

 

[dede61]

Hi power2020,

The OPGW is constructed in two parts, one metalic (electrical conductive + mechanical strenght releive) and secondly an optical fiber bundle, there are different type's with more or less optical pairs. I recently did an application with pilot wire differentials (87L) using optical fibers from the OPGW for the communication between the relays.

regards,

Danny

 

[cuky2000]

Here is a supplemental generic information:

1) How is it constructed for both? There are several OPGW design available in the market. See the enclose picture and link for typical design.

http://www.m-tec.co.za/secondary/opgw/images/blt_cross.gif

2) How is optical signal transfer takes place and how many signals. The number of FO in an OPGW cable varies typically from six to 48 fibers depending of the cable design. Fiber optic cables (OPGW in particular) can carry many teleprotection, voice, data and video communications signal. Bandwidth and other optical limiting factor diminish the performance of the signal. This condition is reached when the signal becomes distorted, principally by dispersion, beyond specified limits.
For reliability and other reasons, some protection schemes are designed with dedicated channels with redundant path.

3) How do we differentiate signals for protection & communication. By multiplexing process. The incoming two or more signals are somehow compressed to be transmitted over a single transmission medium such as FO. Ex. Of this process could be by Time Division Multiplexing (TDM) and Wavelength Division Multiplexing (WDM).

 

[amps21]

Power2020,
Cuky deserves a star for this.

 

[power2020]

thanka cuky.
a star for you.

 

[power2020]

i am sorry Cuky, typing error.
thank you very much for your valuable post.