Incidentally, it was because of this nuclear power plant output always try to maintain a constant. Power had lift, and then – the third step in an accident. To provoke, to extract some absorbing rods of protection. Power has stabilized at the chosen level of 200 MW. Now you can start the experiment. Current, which produces a "ramp-down of the generator," it was decided to apply for a stand-by pumps, in addition to the 6 main water feed to the reactor.
For this – the fourth step in an accident. Includes stand-by pumps, which led to increased water flow through active zone and, consequently, to its rapid cooling. Vaporization in the reactor dropped sharply, the pressure in the drum-separators fall. In order to maintain power had – The fifth step in an accident. Extract more of the rods absorber. Now, at 1:23:04 the experiment began. In preparation for it has already been done 5 Steps to a tragedy. But while this did not know.
The pumps are connected to gradually slow down, "running out" the generator is gradually reduced momentum. Flow of water through the reactor was reduced, the level of evaporation and the pressure grew. The reaction of gaining power, but until then the control system automatically cope with it when – Sixth Step to the accident. 36 seconds After the operator has included disaster protection. The reasons for this action is still completely unclear, and dwell on them we will not. We will only say that the system reacted as expected: the protection of steel rods immersed in the reactor core. But it was too late, they could not cope with the increased capacity. Then the signal was given to the inclusion of maximum protection. All safety rods were thrown down, but the six steps was enough. As said then-secretary-general, "the process has gone" – The first step of an accident. Zirconium fuel rods on the temperature of deformed and destroyed the canals, which are. Absorbing rods failed to fully immerse in their channels and prevented from entering into them a couple of meters. At this time – the second step of the accident. Hot water and steam from the broken channels went in the space of the reactor itself. Thermal reactor power rose "to the unknown values "(all control devices just any high level). And immediately – The third step of the accident. Steam began to decompose into hydrogen and oxygen to form an explosive mixture. She immediately exploded, tearing metalloblochnuyu plate, which protects the reactor from the top, and destroyed all the technological channels. The fourth step of the accident. From the beginning of the experiment up to this point in less than a minute. Depressurize the reactor explosion, unleashed nuclear fuel and have accumulated over running time waste, and threw them into the atmosphere. Further – and the heroic struggle with the consequences, and painstaking investigation, and the creation of "Shelter" – a sarcophagus, covered the 4th reactor, and the present condition of the area – The theme of an individual and a great article. But a short note about the course of the accident that ended. The 'Chernobyl Forum'