Unit general de-energization system equipment

Unit general de-energization system equipment (UGDSE) is intended for:

  • monitoring of state of power Unit electrical part and generation of relevant commands at general de-energization of power Unit according to the assigned algorithm;
  • receipt of discrete signals from power Unit electric equipment, turbine board, from equipment of initiating and actuation part of the engineered safety feature actuation system ESFAS;
  • logical processing of discrete signals;
  • generation of control signals for actuators, power Unit electric equipment and to alarm signaling circuits.

UGDSE  consists of two independent identical sets of equipment, located in different rooms of NPP.

Each UGDSE set consists of two devices:

      1. Data acquisition and processing device (DAPD).

DAPD performs the following functions:

  • receipt of discrete signals from process equipment system and power networks;
  • logical processing of received signals;
  • generation of signals “Unit transfer for house load" and "Unit general de-energization";
  • generation of signals for disconnection of working and redundant inputs for sections of normal operation systems (NOS), of section switches of emergency electric supply system (EESS), and for actuation of diesel-generators of three EESS channels, as well as signals for prohibition of interlocks and remote control in accordance with algorithm;
  • multiplication of processed generalized signals and transfer of discrete signals to commutation device;
  • monitoring of intrinsic operability, operability of commutation device and integrity of communication lines;
  • manual check of operation logic by simulating the input signals without signals output for actuators;
  • generation of signals of good condition and sets being in modes “Check” and “Put out of operation”;

      2. Commutation device.

Commutation device is intended for receipt of signals from DAPD-01 cabinet, for galvanic separation (be means of electromagnetic relays) of signals received from external power circuits of mechanisms, and for transferring the signals in the form of “dry” contacts to actuators.

Every UGDSE set transfers information into the set of data display and logging hardware (DDLH), interfaced with it, via serial interface.