Remarks on Consistent Development of Plant Nodalizations: An Example of Application to the ROSA Integral Test Facility

Table 4

Control logic of Test 6-2 [9].

Event	Condition
Break	Time zero
Generation of scram signal	Primary pressure 84% of initial value
PZR heater off	Generation of scram signal or PZR liquid level below 2.3 m
Initiation of core power decay curve simulation
Initiation of primary coolant pump coastdown
Turbine trip (closure of stop valve)	Generation of scram signal
Closure of main steam isolation valve
Termination of main feedwater
Generation of SI signal	Primary pressure below 79% of initial value
Opening and closing of the SG relief valves	SG pressures 110%/103%
Initiation of auxiliary feedwater	Generation of SI signal
Initiation of asymmetrical SG secondary-side depressurization as AM action to achieve a depressurization rate of 55 K/h in the primary system	30 minutes after generation of SI signal
Initiation of accumulator system	Primary pressure below 29% of initial value
Initiation of LPSI	LP pressure below 8% of initial value