Reliability Analysis of the Trigger Synchronisation and Distribution System of the LHC Beam Dumping System

The Trigger Synchronisation and Distribution System (TSDS) is one of the core components of the LHC Beam Dumping System and an essential element to guarantee that operation with the beam is always safe. The most critical failure of the TSDS is the missed trigger and re-trigger of at least 2 MKD magnets. This report presents the modelling and analysis of the likelihood of the TSDS to develop such a failure scenario during operation. The analysis returns the Safety Integrity Level (SIL) for the TSDS, and the list of the most important contributors. Sensitivity analysis is performed with respect to the failure parameters and with respect to failure dependencies among components that are in the redundant sets. This includes a study of the common cause failures that are in the TSDS architecture. The results in terms of SIL for the TSDS will be compared to the SIL for the previous architecture which was operational until the Long Shutdown 1. Recommendations in order to obtain higher safety by design will also be given.