Chernobyl Nuclear Power Plant I: Control Room

Picture 4 of 14

On June 10 we had the rare experience of touring some facilities at the Chernobyl Nuclear Power Plant.  We’re deeply indebted to Irina Kovbich and other power plant personnel for making this visit possible.  I hope Mike, Chad, and Edward chime in and add a fuller accounting of this tour, but I will get started by posting this modest gallery of photos from the Unit 1 Control Room–certainly a highlight for me.  Click the “Next” button to advance the slide show, and please see the list below for descriptions of the individual photos.

Phase I of the Chernobyl plant consists of Units 1 and 2, two first-generation RBMK-1000  reactors whose design and layout is somewhat different from the later-generation Units 3-4. (click station map at left).   The most obvious difference is the orientation of the nuclear block (the reactor, steam separators, main circulation pumps, etc.) relative to the turbines and ventilation equipment, but other important differences include the lack of pressure suppression pools like those under Units 3-4. Unit 1 began operation in May 1978 and shut down in November 1996.  It was the second-last reactor to close at ChNPP.  Its operational history includes a severe accident that caused fuel damage and released radiation in 1982.  Today, fuel remains in the core and the spent fuel pools.

  1. Here we are (left to right: Edward, Chad, Carl, Mike) behind the reactor control desk.  It’s astonishing they let us take photos in here!  Behind us is a very prominent feature of RBMK control rooms, a servo dial display showing the positions (0-7 meters insertion) of various types of control rods and in-core instrumentation.
  2. East-to-west view of control room.  In the foreground is “A” desk, with operator interfaces for the old “SKALA” process computer, for moving control rods, for reading the signals from various detectors, for measuring reactivity, and so forth.  Next is “P” desk, with controls for condensate and circulation pumps, valves, and other components of the main plant hydraulics.  Finally, in the background, is “T” desk, where the turbogenerators are controlled.
  3. Chad in front of “A” desk, Edward at “P” desk, Carl talking to the engineer at his desk.
  4. The senior engineer for Unit 1, a 24-year employee of ChNPP who began his career in Unit 3.  He shared opinions on diverse subjects, ranging from the challenges of medical care for ChNPP workers, the relative ease of operating RBMKs versus VVERS (where operators are kept as busy as “pianists”), the differences in operator training between the US and the former USSR.  He explained many of the control room features.
  5. Mike in front of the computerized reactor control system and its display in the background.  I don’t have a good understanding of how the operator uses this system or what its display indicates.  The original SKALA computer (a slow machine with core memory and tape drives) was evidently replaced with something better during Unit 1’s later career.   The compartments east of the control room still bear its name, however.  Please comment if you know how this thing works.
  6. Lamp covers for the computerized control system display, labeled according to the channel number in the reactor and color-coded to correspond with the channel contents (CPS channels, pressure tubes, detectors).
  7. Closeup of servo dials on CPS and instrumentation status display, color-coded to correspond with channel contents.  I believe the blue dials, with 0 meters insertion at the six-o’-clock position, are  for the axial shaping rods entering below the core, and dials of other colors correspond to various groups of manual and emergency protection rods entering from above the core.  I was told the black boxes, e.g. Channel 24-22, are axial flux monitors.  I’m thinking the control channels without dials, e.g. Channel 30-27, correspond to automatic regulating rods.  I’m not sure though.
  8. View of “A” desk prominently featuring a reactivity monitor, ash tray, stopwatch mounted to desk with key attached (?), communications microphone, etc.
  9. Closeup of reactivity meter and SCRAM buttons on “A” desk.  The meter computes reactivity in terms of the effective delayed neutron precursor fraction (βeff) using the signals from ion or fission chambers.  The SCRAM buttons are sealed with wax seals.  The level-5 protection system, AZ-5, is triggered by the top center button and sends all withdrawn rods into the core.  The BAZ system, buttons at right, is a special set of control rods that is capable of entering the core faster than the others.
  10. Manual reactor operating controls on “A” desk.  The meters seem to indicate reactor period (infinity – 20 seconds) and detector current (proxy for power).  The buttons in front are used to select CPS channels in order to move the rods therein.
  11. Clock, water level gauges, parameter display systems
  12. Pump and valve switches on “P” desk
  13. Turbine power meter (0-600MW) on “T” desk.  Each of the two turbogenerators is rated at 500 MWe.
  14. Electrical controls at the west end of “T” desk
 
June 20th, 2010 6:13 am by Carl
Chernobyl Nuclear Power Plant
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12 Responses to “Chernobyl Nuclear Power Plant I: Control Room”

  1. Susan Mills says:

    these are wonderful photos Carl- in Picture 11, on that CRT, was that a logic diagram for the electrical systems?

    Boris Stolyarchuk was one of the operators who pressed the AZ-5 annunciator that night; it was already too late~

    did you get to go in the Block 4 control room?

  2. Susan Mills says:

    So in Picture 7, each of these annunciators corresponds to a particular fuel channel in the core? the Block 4 reactor had about 1661 fuel channels I believe~

  3. Susan Mills says:

    they dismantled much of the control boards in the Block 4 control room because it was still functional instrumentation and installed them in other units-

  4. Carl says:

    Hi Susan! I think the barely-visible displays in Pic 11 relate to parameters for the steam drum separators. I can’t really tell from the photo though. I am certain it is hydraulic rather than electrical in nature. We didn’t make it to the Unit 4 control room. Workers are in the process of walling it off right now. As our guide said, “Maybe in your next life.” (I was kinda hoping for this one sometime.) Truthfully, although I would have loved to spend a few minutes there, the fact is we had other priorities on our tour. CR-4 has received a steady stream of visitors with cameras; the main circulation pump rooms and the administrative bunker are significant places that I have always been curious about but don’t get attention. I’ll be posting photos from those spots soon. Take care– Carl

  5. Natasha says:

    On photo 6 what does the lamp cover with the blue star-burst indicate? – aka number 36.40?

    Stunning photos

  6. Natasha says:

    Also, why are there no eights or nines in the sequences – the numbers on the lamp covers jump from seven up to zero – for instance, 35.37 goes to 35.40 and 47.35 goes to 50.35..

  7. Carl says:

    Hi Natasha,

    I don’t know what the blue star-burst means. It was drawn on by hand, on a white lamp cover (signifying an ordinary fuel channel). Maybe this particular fuel channel “ran hot” or leaked or was empty or had a special test assembly in it? One other channel experienced a fuel failure that I wrote about in another post, and has been hatched out in pen, in a different manner.

    You noticed that there are no #8 or #9 rows or columns. Also a good question for which I don’t have an answer. Thanks for your observations. I’ll just have to get someone at ChNPP to answer.

  8. Andre says:

    Very interesting pictures. I have one question, do you have a look into the core design, we call that paper Plant operational curves and tables – power defect, void efect…etc.

  9. Dimitris says:

    Great photos. Thanks for posting them.

    I think that there are no 8s or 9s in the sequences just because the numbers are in octal (3 bits per number).

  10. daniel vilchiz says:

    dear people and employees of the past chernobyl disaster, why did chernobyl blew up in the first place and while checking the blue prints, either reactor one or two’s energy started to rise and maybe less water to the fuel rods may be the problem of not cooling the rods and control rod had melted. the pressure from the reactor blew up and the remaining energy exerted from the reactor, radiation with the wind blowing across Priyat to greenland.

    i hope you may believe of what i said because of my research of the blueprints and past nuclear disasters Thank you.

    sincerely Daniel

  11. I will appreciate if you continue this in future. Lots of people will be benefited from your writing.

  12. Andressa says:

    I agree, some countries inculding the US and Japan have a passive policy about crating safety procedures towards natural disasters and nuclear damage. US politics have recently recognized that they have a weak protection regarding nuclear reactors. Hence, they have currently decided to reinforce or enhance its safety on behalf of the people. However, is it necessary to scream more than seven times as toni mentioned in order that politicians listen to us? because its very sad and now Japan is severely suffering the consequences.

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