The HL-LHC magnets and cold powering systems are planned to be tested individually on dedicated test benches in the SM18 test facility at CERN or at the collaborators test facility (e.g. at Fermilab in the USA). The HL-LHC IT STRING will reproduce on the surface the configuration of the left side of Point 5 with the goal of the final testing of the IT zone in a complete and combined configuration where several magnets will be connected in a common circuit both electrically as for the cryogenic cooling.

The powering will be done through the SC link system and the standard HL-LHC power converters, as well as the quench detection and protection will follow the baseline design of the project. Although the cryogenic cooling will target the 1.9 K temperature, the system insuring the cooling and the total capacity for pumping will not be the one of the HL-LHC.

Another major difference between the configuration of the IT zone on P5L and the HL-LHC IT STRING will be the absence of the beam screen in the HL-LHC IT STRING; apart from the fact that the slope of the tunnel will not be reproduced. This decision was taken in 2019 following an internal review of the configuration and budget of the HL-LHC IT STRING. This change of configuration allowed reducing the total budget of the IT STRING. The qualification of the new concept of the beam screen will be done off line, individually and on model magnets. A recent review of the schedules of the main components led us to set up a new baseline schedule of the IT STRING, which is also delayed by approximately 6 months, while the operation period is optimised and reduced to a total duration less than 1.5 years, including also the yearly shut down periods.