RELAP5/MOD3.3 Code Validation with Plant Abnormal Event

Table 3

Time sequence of main events during transient.

Event	Measurement	Calculation
Turbine flow reduction	0 second–5 seconds	0 second–5 seconds
Operator action (start of governor valve opening)	16 seconds	16 seconds
SI signal on low steamline pressure	17 seconds^*	16.7 seconds
SI pump injection start	21 seconds	22 seconds
SG power operated relief valve (PORV) opening	27 seconds	31 seconds
AFW flow actuation	42 seconds	42 seconds

^*based on 25 seconds delay of AFW actuation.