Development of the Safety System for the Inner Tracking System of the ALICE Experiment

Pascal Herve Blanc,Xavier Pons,Patricia Mendez Lorenzo,C Biscarat,C.I Rovelli,B Hegner,S Campana,G.A Stewart,S Roiser

doi:10.1051/epjconf/202125104004

Pascal Herve Blanc, Xavier Pons + Show 7 more

Open Access

https://doi.org/10.1051/epjconf/202125104004

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Abstract

During the LHC Long Shutdown 2, the ALICE experiment has undergone numerous upgrades to cope with the large amount of data expected. Among all new elements integrated into ALICE, the experiment counts with a new Inner Tracking System (ITS), with innovative pixel sensors that will substantially improve the performance of the system. The new detector is powered up through a complex Low Voltage (LV) distribution, increasing the power dissipated by the detector and requiring the installation of a large number of temperature measurement points. In 2020, a new safety system has been developed to distribute the ITS LV interlock system and to monitor the new temperature values. The safety system is based on a Siemens S7-1500 PLC device. The control application governing the PLC has been configured through the UNICOS-CPC infrastructure made at CERN for the standardisation of industrial applications. UNICOS-CPC enables both the automatisation of control tasks governing the PLC and the interface to the WinCC OA based SCADA system. This paper provides a complete description of the setup of this safety system.

Highlights

During the LHC Long Shutdown (LS2), the ALICE [1] experiment has undertaken a major upgrade of its tracking detector [2]
Among all new elements integrated into ALICE, the experiment counts with a new Inner Tracking System (ITS), with innovative pixel sensors that will substantially improve the performance of the system
The ITS2S safety conditions provided by ALICE are distributed in code blocks involving temperature threshold conditions for the Analogue Input (AI), status of the DIs and associated interlock values set through the DOs

Summary

INTRODUCTION

During the LHC Long Shutdown (LS2), the ALICE [1] experiment has undertaken a major upgrade of its tracking detector [2]. The project has used the UNICOS-CPC (Continuous Project Control) [6] interface, in particular the UAB (UNICOS Application Builder v1.2.10) toolkit included in UNICOS-CPC. Both hardware setup of the safety system and its control software structures have been completed and validated

The hardware architecture of the ITS2S

The software structure of the ITS2S

FORMALISATION OF THE ITS2S PROJECT

The logic specifications of the ITS2S project

THE SUPERVISION OF ITS2S FROM WINCC OA

SUMMARY