Quote from INSAG-7 https://www-pub.iaea.org/MTCD/Publications/PDF/Pub913e_web.p...
reply> neither the reactor power nor the other parameters (pressure and water level in the steam separator drums, coolant and feedwater flow rates, etc.) required any intervention by the personnel or by the engineered safety features from the beginning of the tests until the EPS-5 button was pressed. The Commission did not detect any events or dynamic processes, such as hidden reactor runaway, which could have been the event which initiated the accident. “
Sure, I'm just saying the power increase did happen, according to both INSAG-1 and INSAG-7. Neither INSAG-1, INSAG-7 nor Legasovs report claims there is a rapid increase in power before AZ-5 is pushed. The claim in INSAG-1 is that this power increase was the start of a positive-feedback loop that caused the explosion. The claim in INSAG-7 was that the power increase was not a safety problem, except to the extent it caused the operator to push AZ-5.
replyThe AZ-5 button was pushed as normal shutdown procedure as the test had been completed, not as a reaction to some event.
replyI can't find any description of the test across the three reports mentioning that that emergency stop button is supposed to be pressed as part of the test. AFAICT the test wasn't even completed when the button was pressed as the purpose of the test was to demonstrate that the emergency core cooling system could run for at least 40 s (INSAG-1 page 17) after closing the turbine emergency stop valve. That valve was closed at 01:23:04 and AZ-5 was pressed at 01:23:40.
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