FPU01

The main function of the fiber protection unit (FPU) is to protect against optical fiber line failures. The unit has a 50:50 (3dB) power splitter in the transmit direction and a 1x2 optical switch in the receive direction. The unit will switch to the protection path when it detects the loss of optical power or when the optical power is decreased below the set threshold. The main control interface to this module is I2C from the backplane. The protection switch can be configured as revertive, non-revertive and forced switching by the user.

This module is connected to the optical adaptor having 1/3rd slot capability. The optical adaptor card in turn provides the control interface from the backplane. The FPU01 is supported in the 1/3rd and 2/3rd slots as well but for 2/3rd slot with mechanical adaptor card FPUADP01.

Front panel

The following figure shows the front panel of FPU01 card:

Power specifications

Power specifications – FPU01 card

Functional description

The following are schematics of the FPU01 card:

The Tx and Rx ports are connected to any optical interface which needs to be protected for optical fiber cut in the network side. The Tx-W and Tx-P are the work and protect transmit ports, respectively which need to be connected to the work and protect optical fibers. Similarly, Rx-W and Rx-P are the work and protect receive ports, respectively which need to be connected to the work and protect optical fibers.

Typical specifications

Typical specifications and functionalities of the FPU01 card are as follows:

• Supports C-band.
• Supports alarm monitoring.

The following table summarizes the different parameter and typical values:

Typical Specifications – FPU01 Card