The Système d'aide à la conduite, à l'exploitation et à la maintenance (SACEM) is an embedded, automatic speed train protection system for rapid transit railways. The name means "Driver Assistance, Operation, and Maintenance System".
It was developed in France by GEC-Alsthom, Matra (now part of Siemens Mobility) and CSEE (now part of Hitachi Rail STS) in the 1980s. It was first deployed on the RER A suburban railway in Paris in 1989.
Afterwards it was installed:
- on the Santiago Metro in Santiago, Chile;
- on some of the MTR lines in Hong Kong (Kwun Tong line, Tsuen Wan line, Island line, Tseung Kwan O line, Airport Express and Tung Chung line), all enhanced with ATO,[1]
- on Lines A, B and 8 of the Mexico City Metro lines in Mexico City;[2] and
- on Shanghai Metro Line 3.[3]
In 2017 the SACEM system in Paris was enhanced with Automatic Train Operation (ATO) and was put in full operation at the end of 2018.[4]
The SACEM system in Paris is to be enhanced to a fully fledged CBTC system named NExTEO. First to be deployed on the newly-extended line RER E in 2024, it is proposed to replace signalling and control on all RER lines.[5]
Operation
The SACEM system enables a train to receive signals from devices under the tracks.[6] A receiver in the train cabin interprets the signal, and sends data to the console so the driver can see it. A light on the console indicates the speed control setting: an orange light means slow speed, or 30 km/h (19 mph); a red light means full stop. If the driver alters the speed, a warning buzzer may sound. If the system determines that the speed might be unsafe, and the driver does not change it within a few seconds, SACEM engages the emergency brake. SACEM also allows for a reduction in potential train bunching and easier recovery from delays, therefore safely increasing operating frequencies as much as possible especially during rush hour.
References
- ^ "MTR > Tenders & Contracts". www.mtr.com.hk. Retrieved 2021-12-17.
- ^ "Mexico City (Mexico) Lines A, B and 8 - SACEM high performance Automatic Train Control for driver-based operation" (PDF; 600 kB). Siemens SAS; Infrastructure & Cities Sector; Mobility and Logistics Division. 2015-03-05. Retrieved 2017-12-23.
- ^ 张郁; 黄佩伟 (2004). "上海轨道交通3号线轨道电路分析" [An analysis of track circuits deployed on Shanghai Metro Line 3] (in Chinese). 城市轨道交通研究. Retrieved 2020-05-12.
- ^ "Alstom-developed Automatic Train Operation system successfully enters service on the RER A". ALSTOM Holdings. 2017-10-05. Retrieved 2017-12-23.
- ^ "RER E – soon one train ahead thanks to NExTEO …". SNCF Réseau. 2017-07-20. Retrieved 2017-12-23.
- ^ "Système d'Aide à la Conduite, à l'Exploitation et à la Maintenance". Institution of Railway Signal Engineers. 2003. Retrieved 2017-12-23.
External links
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This page was last edited on 26 October 2023, at 11:19