During October, November and December 2018, some students of the “Primo Levi” institute, Quartu Sant’Elena (CA) contributed to the EEE Project, within the ASL Project, with the assembly of 60 DC-DC converters. They will be used to supply HV to the MRPC chambers in several telescopes.
The students, specialized in electronics, Marco Canneva and Riccardo Onnis, cooperated with the INFN of Cagliari for 30 hours. During this time, with the help of Stefano Boi, Mattia Taccori and dr. Corrado Cicalò, 30 positive modules and 30 negative modules were assembled.
Every converter was assembled by hand following the same procedure:
• Welding of the 10MΩ protection resistor inside the high voltage connector;
• Insulation of the aluminum box by means of plastic sheath on the whole inner surface;
• Fixing of the input, output and monitoring connectors;
• Electrical connection between Lemo monitoring connectors and the high voltage connector through the common reference;
• Connection between converter’s input and low voltage connectors of the box;
• Connection of the converter’s output wire to the high voltage connector and to the voltage divider made of the 1GΩ and 10MΩ resistors for the voltage monitoring through the appropriate Lemo connector;
• Connection of the current return wire to a voltage divider made of two 10MΩ resistors, linked to the appropriate Lemo connector for the current monitoring;
• Test of the individual boxes powering them on with different voltages and verifying the right functioning by means of the monitoring of the output values.
The ASL Project has then been presented to the 10th Conference of the Centro Fermi at the Cavallerizza Reale, University of Turin, in which the students Marco Canneva and Riccardo Onnis, during the time dedicated to the contest “La Parola alle Scuole”, won the second award.