A. Colinet, R. Murillo Garcia, D. Nisbet, J. Ridewood, I. Romera Ramirez, F. Maria Velotti
Certain PCs will be fully renovated (power part + FGC3). Others will only have renovated controls (FGC3).
In the draft ECR, only around half of the bumpers will be renovated (the horizontal ones, and not the vertical).
Ok to have no LSA settings for non-SX cycles.
Ok to have a fixed non-PPM tolerance for these PCs as they don't need sub-percent regulation.
Only 4 extraction sextupoles are used for operation: LSE.10602, LSE.22402, LSE.40602, LSE.52402. The others are only used for specific MDs, and are not planned to be used in the near future. Only the operational ones will be connected to the BIS, and the spares will be routed to the racks hosting the concentrators, but left disconnected.
Conclusion:
These devices require a much finer regulation in the order of 0.1%-0.2% (i.e. 1000ppm - 2000ppm). Action Francesco: Confirm the requirements for the LSS2/4/6 bumpers with absolute values in Amps.
Not following the function will certainly lead to high losses + can very quickly become hazardous to the machine.
As they are ramping with the beam, i.e. reasonably slowly, David thinks that the PCs should be able to follow the programmed functions during ramp up within the requested tolerance. This should at least be the case with the latest PCs (Polaris), planned to be installed in LS3. Not all extraction bumpers will be renovated though.
Action David + Raul: Confirm the point above once the tolerances are available from Francesco.
Note: when using a PPM threshold without LSA settings, there is no regulation evaluation for this user, and in this case the User Permit is True.
There are really only two options for the settings:
Following circulation of EDMS 3253361, EPC (Ivan) will give feedback next week to see if windowed tolerances are indeed required based on the performance of the new PCs.