Mobility and Transport

Rail

ERTMS - Levels and Modes

ERTMS - Levels and Modes

The levels and operation modes are basic concepts of the ETCS system. A short definition can be given as follows:  

  • Level 1 involves continuous supervision of train movement while a non-continuous communication between train and trackside (normally by means of Euro-balises). Lineside signals are necessary and train detection is performed by the trackside equipment out of the scope of ERTMS.
  • Level 2 involves continuous supervision of train movement with continuous communication, which is provided by GSM-R, between both the train and trackside. Lineside signals are optional in this case, and train detection is performed by the trackside equipment out of the scope of ERTMS. 
  • Level 3 is also a signalling system that provides continuous train supervision with continuous communication between the train and trackside. The main difference with level 2 is that the train location and integrity is managed within the scope of the ERTMS system, i.e. there is no need for lineside signals or train detection systems on the trackside other than Euro-balises. Train integrity is supervised by the train, i.e. the train supervises being complete and not having been accidentally split.
  • In addition, there are two more levels defined: Level 0, which is meant for trains equipped with ETCS running along non-equipped lines; and Level STM, which is meant for trains equipped with ETCS running on lines where the class B system needs to be operated. Regarding the STM level, the ETCS acts as an interface between the driver and the national ATP.

Operation modes can be defined as different conditions required for managing different situations regarding the status of the trackside and the train itself. Unlike the ETCS levels (associated with train-trackside communication), ETCS modes are related to the operational circumstances of the line or the onboard equipment status.

The main ETCS mode is Full supervision. The ERTMS/ETCS on-board equipment will be in Full Supervision mode when all train and track data, which is required for complete supervision of the train, is available on board. In this mode, the on-board ERTMS/ETCS equipment is responsible for train protection.

There are also other modes for different operational situations, the following are some examples: there is a shunting movement mode, i.e. shunting mode, a mode that allows the train to enter an occupied section, i.e. on-sight mode or a mode that allows train movement under driver responsibility, i.e. staff responsible mode. There are also modes related to specific information that the trackside ERTMS subsystem is able to send, for example the Limited Supervision mode enables the train to be operated in areas where trackside information can be supplied to carry out background supervision of the train.