Upgrading hydrogen unit panel at the Temelín NPP

In the planned outage of the Temelín NPP Unit 2, we carried out a complete upgrade of 2HP08 hydrogen unit panel within the project “E077 – improvement of 1(2)HP08 gas panel”. It consisted in replacing the hydrogen purity analyzers in the generator with a new type of CALDOS 27 thermal conductivity analyzers produced by ABB and adding new hydrogen concentration measurements on a catalytic principle.

When upgrading the hydrogen unit panel, we also completely replaced the original copper routes for hydrogen supply from the generator with nine new stainless steel routes, including a completely new instrumentation inside the 2HP08 panel, all in EX (explosive atmospheres). Furthermore, in the existing 2JQ02 cabinet we replaced the control panel for measuring hydrogen concentration in the engine room with a new type of Touchpoint Plus control panel by Honeywell, including the addition of brand new measurements of hydrogen concentration. At the same time, the links to the PCS superordinate control system were modified. The entire upgrade could only be carried out in a limited period of the 2GO19 outage.