MAGNET

Maintenance work and consolidation activities on the magnet cryogenics and its power distribution are progressing according to the schedules.

The manufacturing of the two new helium compressor frame units has started. The frame units support the valves, all the sensors and the compressors with their motors. This activity is subcontracted. The final installation and the commissioning at CERN are scheduled for March–April 2014.

The overhauls of existing cryogenics equipment (compressors, motors) are in progress. The reassembly of the components shall start in early 2014.

The helium drier, to be installed on the high-pressure helium piping, has been ordered and will be delivered in the first trimester of 2014.

The power distribution for the helium compressors in SH5 on the 3.3kV network is progressing. The 3.3kV switches, between each compressor and its hot spare compressor, are being installed, together with the power cables for the new compressors. The 3.3kV electrical switchboards in SE5 will be consolidated. The consolidation will take place during the cooling and ventilation maintenance scheduled for the beginning of May 2014, to avoid any impact outside this period on the detector operations. The modifications include the connection of the compressor switch cells on the LHC machine power network, the change of the switch control coils to 48 V, and the reconfiguration and commissioning of the three PLCs for the auto transfer from the LHC machine power network to the LHC loop power network.

As part of the general consolidation of the uninterruptible power supplies (UPS) at Point 5, the UPS for the cryogenics and the magnet control system in the USC5 and SHL5 will be replaced, by March 2013. The existing safe room for cryogenics in SHL5 will be moved, and the cryogenics control racks and the UPS will be installed in SH5.


by Benoit Curé