Sensitivity Study on Availability of I&C Components Using Bayesian Network

Table 2

Failure data for I&C components [17, 23, 24].

	ID	Failure modes	Mean (𝜆)	Reference
𝑋𝑖1	TR	Pressure sensor failure	1.7𝐸−06/h	IAEA-TECDOC-930
𝑋𝑖2	PT	Sensor/transmitter fail to operate (FTOP)	1.17𝐸−04/d	NUREG-6928
𝑋𝑖3	AI	Analog input failure	1.0𝐸−04/d
𝑋𝑖4	DI	Digital input module failure	2.88𝐸−04/d
𝑋𝑖5	BP	Bi-stable fail to operate (FTOP)	5.0𝐸−04/d	NUREG-6928
𝑋𝑖6	CP	Analog (pressure) processor logic module fails	1.57𝐸−04/d	NUREG-5500, V.2
𝑋𝑖7	DO	Channel (pressure/temp) relay fails	3.94𝐸−05/d	NUREG-5500, V.2
𝑋𝑖8	ST	Breaker shunt failure	5.81𝐸−04/d	NUREG-5500, V.2
𝑋𝑖9	UV	Breaker under voltage failure	2.54𝐸−04/d	NUREG-5500, V.2
𝑋i 10	CB	Circuit breaker fail to open/close	2.5𝐸−03/d	NUREG-6928
𝑋	CRDM	CRDM failure	1.5𝐸−05/d