Beneficiary Organisation Details
- Ignalina NPP
http://www.iae.lt
Project Aims
The main purpose of this project was to provide for development of design, design substantiation, manufacuring, supply, delivery, works testing and commissioning of second Diverse Shutdown System (DSS) for Ignalina NPP Unit 2. The development and installation of such a system was requested as a result of the plant safety analyses performed. This system had to be independent from the existing Control & Protection System and had to employ diverse equipment. This was essential to provide the necessary two Strong Lines of Defense against the most severe accidents. According to the requirements of VATESI, the DSS had to be implemented at INPP Unit 2 not later than by the end of 2004. The new DSS had to provide fast shutdown for all accident sequences and cover all accidents within design basis domain for INPP.
Project Results
The Second Diverse Shutdown System has been developed and installed successfully and Unit 2 at Ignalina NPP. The system design and operational aspects have been reviewed by the Regulatory Authority (VATESI) Technical Support Organization. Two additional modifications to the system have been proposed for consideration and implementation in future:

• implementation of a rector scram signal on low flow in the Group Distribution Header (GDH); and
• separation of the wiring in the vicinity of the Fortress bypass switches in each of the three Reactor Scram Output Relay Device (ORD) cubicles.

The Second DSS was licensed and put into operation at Ignalina NPP unit 2 as planned by the end of 2004.
The budget for this project was 13 400 000 euro.
Further Project Results
Further information on the project results could be sought from the beneficiary organisation.