Innovative timer relay delayed on drop-out without auxiliary supply

The relay, developed by Arteche, has been designed according to the requirements of Thales Transportation Solutions in Canada, who includes it in their onboard railway signalling and control systems CBTC (communications-based train control).

The range of time delay relays from Arteche offers multiple timing functions in one single device. With regards to the delay on drop-out function, normally two different signals are available (command and supply) to operate the relay.

Following the client´s requisite, who for security reasons needed to provide only one signal to their design, Arteche has developed the TDF-4DO delayed on drop-out timer relay. This relay, unlike the conventional ones, is able to hold its four output contacts in the working position (relay energized) without any help from an auxiliary supply, as it feeds itself by means of a capacitor system located inside the relay. Thus, it is possible to set a delay from 0 to 1.000 ms with a single signal that acts as command and supply at the same time.

Additionally there is the possibility to choose between a fixed and an adjustable (through a potentiometer) timing variant. This way during the testing phase the client can manually adjust the timing according to the specific requirements of each project. Once the particular delay is set, the client selects a factory-configured fixed timing model, avoiding therefore unwanted manipulations due to the relevance of the relay within the system and saving field configuration time and costs.

Among others, the relay will be installed in the onboard CBTC system of the trains belonging to the “Doha Metro” project in Qatar, one of the world’s largest metro systems, whose completion is expected by October 2019.