Page - 1091 - in Book of Full Papers - Symposium Hydro Engineering

In addition, the weather station has been integrated into the automated data collection system by communicating the automation server with the station logger. As a complementary system, a high precision Global Navigation Satellite System (GNSS) has been installed. It allows the displacements measurements of 3 points located at the dam crest, both horizontally and vertically, using an external pillar as reference, allowing to obtain post-process results working every hour, 4 hours and 24 hours. In this last case, a sub-millimeter precision is obtained. For real-time monitoring and for the analysis of all the information, ADAS auscultation software has been installed, with customised developments for this project. This software allows real-time monitoring of the system, generation of graphs and reports and alarm management, among other functionalities, operating on a multiuser Web environment, allowing several technicians to work on the system at the same time. The structure of the ADAS is based on industrial decentralised periphery automation, in this case composed of a main box that houses the PLC (Programmable Logic Controller) provided with a touch panel with remote connection, and four secondary boxes, racks, all connected in a ring via optical fibre and secure power supply via batteries. Equipment with galvanic isolation and surge arresters has been placed at strategic points to make the system more robust. The GNSS communicates via optical fibre with the main box, which is connected to the server installed in the control and emergency room where the GNSS and ADAS software is installed. The touch panel of the main box enables the parameterisation and supervision work on the dam, as well as stopping logs for maintenance work and alarm management. As all the equipment is in the same network, the panel can be remotely accessed from any box, thus allowing the monitoring and parameterisation of the instrumentation from other galleries where there are automation boxes, making these tasks much easier. The communication between the instrumentation and automation box is performed with multi-wire shielded sheaths from each device to the box, thus avoiding interconnection boxes, all channelled in separate trays of the power supply sheaths, avoiding electromagnetic noise and guaranteeing the quality of the signals. All the instrumentation is adapted to be able to make a parallel manual reading, allowing data contrast and validation of both systems. The equipment is all standard, allowing easy maintenance and rapid device replacement times. The system is already equipped for an expansion of about 20%. 2.3. MEASURING RANGE OF UPLIFT PRESSURE, MEASURED THROUGH PIEZOMETERS The automated measurement of uplift pressure is performed through 25 piezometers as presented in Fig. 2. 1091