] [ 34 ] This restricted any further rise of reactor power, and made it necessary to extract additional control rods from the reactor core in order to counteract the poisoning. The operation of the reactor at the low power level and high poisoning level was accompanied by unstable core temperature and coolant flow, and possibly by instability of neutron flux. Various alarms started going off at this point. The control room received repeated emergency signals regarding the levels in the steam/water separator drums, and large excursions or variations in the flow rate of feed water, as well as from relief valves opened to relieve excess steam into a turbine condenser , and from the neutron power controller. In the period between 00:35 and 00:45, emergency alarm signals concerning thermal-hydraulic parameters were ignored, apparently to preserve the reactor power level. [ 35 ] After a while, [ vague ] a more or less stable state at a power level of 200 MW was achieved, and preparation for the experiment continued. As part of the test plan, extra water pumps were activated at 01:05 on 26 April, increasing the water flow. The increased coolant flow rate through the reactor produced an increase in the inlet coolant temperature of the reactor core (the coolant no longer having sufficient time to release its heat in the turbine and cooling towers), which now more closely approached the nucleate boiling temperature of water, reducing the safety margin . The flow exceeded the allowed limit at