The years 2011 and 2012 were excellent for the LHC in terms of performance, and also availability of power converters. However, the experience shows that warm magnet power converters are particularly sensitive to network perturbations, specially the RPTG types [810A/950V] which supply RD1 and RD34 circuits. Indeed several beam dumps have been triggered by these converters (see presentation Change In Powering Interlocks at MPP workshop in March 2013). In April 2012, the TE management has decided to replace the RPTG power converters by new switch mode power converters (TE-TM46 of 03-April-2012).
There are 4 warm magnetic circuits associated with the RPTG power converters. Two of those are placed at the sides of the experiences, while the other two are placed at the sides of the beam cleaning zones.
The following circuits of the LHC are concerned by this consolidation:
Project Management: .gdpm
Technical documentation: .edms
Functional Specification: .edms
Converter pre-studies: .edms
Protection Coordination Study, RD1 and RD34 converters: .edms
Engineering Change Request - RPTG Power Converters Consolidation .edms