For the rundown test, after the valve cut-off, it is irrelevant whether the reactor was shut down or not. The working plan for the test only specified that it was supposed to run before a planned maintenance period, so the shutdown was implied. During previous tests, the AZ-5 signal was wired to the valve cut-off signal and was sent automatically at the same moment. It is not clear why this changed in 1986, but the outcome would have been the same if AZ-5 had been pressed 35 seconds earlier.
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