Plant Hardware

General Description

The plant hardware input files establish the linkage between the RELAP5 thermal hydraulic model and the ADS-IDAC environment, and manage hardware failure events. These files form the interface between the cognitive human reliability model and the underlying reactor plant simulation.

ADS-IDAC supports two types of hardware failure events:

• Time-dependent failures — described in Initiating_Event.txt; initiate hardware failures at a prescribed simulation time. These generate only a single failure event sequence branch.
• Conditional failures — triggered when a specified component changes its operating state. These generate two event sequence branches: a success path and a failure path. If a recovery is attempted, two additional branches are generated (successful recovery and permanent failure).

Both failure types permit the operators to attempt to recover failed equipment.

A third route, fault-tree quantified failures, takes the failure probability from a logic diagram over component failures instead of from a distribution on the input line. It covers support systems that RELAP5 does not model at all (emergency AC power, service water) and hardware whose demand failure is better described by a tree. This route is not active in the shipped builds — see Support system fault trees.

Input Files

File	Description
ControlPanel.txt	Describes all ADS-IDAC control panel elements — parameters, component state indicators, support system displays, controllers, and alarms. This is the central interface between the simulated operators and the RELAP5 plant model.
Initiating_Event.txt	Defines time-dependent hardware failure events that initiate at a prescribed simulation time.
RELAP5_channels.txt	Establishes RELAP5 communication channels that allow information exchange between RELAP5 and the ADS-IDAC environment.
SystemReliability.txt	Defines conditional hardware failure events triggered by changes in component operating state. Three sections: demand failures, running failures, and fault-tree driven failures.
*.fta	Fault trees for support systems that RELAP5 does not model (Input/SupportSystemsReliability/) and for the fault-tree section of SystemReliability.txt (Input/HardwareReliability/).

SPDS_input.txt (legacy, not read)

Reference cases also ship Input/Indicators/SPDS_input.txt (Safety Parameter Display System). The control-panel SPDS module that consumed it is disabled in the current code, so the file is not read at runtime. The active safety parameter inputs are the per-operator files KB_OAT_Safety_Parameters.txt (and the KB_ODM_ equivalent).