Resif’s broadband seismological station control cabinet
Consisting of a Low Voltage board and a Very Low Voltage board, it aims at minimizing the maintenance interventions of the operators in the field thanks to :
- technical information feedback that enables the anticipation of failures and the schedule of field interventions
- the possibility for operators to intervene remotely on the power supplies of the various devices of the station
- the ability of the cabinet to handle certain situations on its own, such as loss of communication with the observatory, or loss of mains power.
It was developed in the framework of an innovation partnership, a public contract during which several companies worked in parallel on the specific needs of our permanent stations. Each study produced a prototype that was put into a field situation for several weeks. At the end, the contract for mass production was awarded to the company ABAC  whose cabinet proved to be the most efficient.
The design of this cabinet is based on a commercially available Tbox PLC and on an Energy Management Card (CGE in french) developed specifically to meet our needs: capable of managing up to 5 independent lines of 24V batteries, it allows, in the event of loss of mains power, to put the station in an “energy saving” mode where only scientific acquisition works. From time to time, it puts the whole station back into operation in order to exchange service information with the observatory.
For the isolated stations that we have not been able to connect to the electrical grid, the same 220V alternating current is supplied by a device on solar panels . In addition to the interest of having the same cabinets on all our sites, recreating 220V eliminates the constraint of distance between the solar panels and the cabinet, a constraint inherent to the direct current supplied as standard by the solar panels. In this configuration, thanks to the CGE, it is possible to program a maximum charging current and a specific time slot to ensure optimal charging of the station’s batteries, regardless of the amount of sunshine.
In order to adapt to a maximum number of situations, the RESIF cabinet can manage Low Voltage and Extra Low Voltage lighting. It also has two 220V terminal blocks that can be controlled remotely or triggered by a contactor (initially designed to operate a lifting pump in the presence of water). Depending on the site configuration, the two boards can be several dozen metres apart.
The control panel’s PLC offers a Web interface normally intended for an operator on site but which, depending on the quality of the telecommunication link, can be used remotely. Otherwise, all information and actions can be managed by web service, which makes it possible to integrate the dialogue with the cabinet with supervision tools already present in the observatories.
Olivier Charade, CNRS-INSU, Division technique – olivier.charade[at]cnrs.fr
 ABAC, groupe CFH, 15 rue de Vaux, 77710 VILLEBEON – Tel. +33 1 60 96 55 66
 Mechanical design and parametrization according to the site by the company Ciel Energie, Rue des Alpes, ZA Les Bastides Blanches, 04220 SAINTE TULLE – Tel. +33 6 03 73 22 90
Outdoor cabinet of the Résif-RLBP REYF station at the Montagne du Rey, on the commune of Castet (Pyrénées-Atlantiques) © Hélène Pauchet, OMP Toulouse. To know more about it.
Inside the outdoor cabinet of the station SDOF in Saint-Denis-d’Oléron (Charente-Maritime), with the control/command cabinet on top. The low-voltage board, on the left, fits into a 19″ rack; the low-voltage board, on the right, forms an L shape to adapt to narrower technical rooms (seen from the perpendicular part in the right frame) © Pierrick Gernigon and Damien Fligiel (Osuna), and Olivier Charade (CNRS-Insu, Technical Division) for the legends – To know more about it