Power tests of single and twin aperture superconducting dipole models for LHC

High field superconducting magnets working at superfluid helium temperature are requested for the 7 TeV LHC accelerator. Several single and twin aperture 1 m long dipole models were measured to compare the differences in behaviour due to design and fabrication. They are shown to be valid models to predict the behaviour of full length magnets. The analysis of the numerous data collected during the performance tests of these magnets allows the proposal of some guidelines to understand the causes of the training quenches. Short sample measurements of both single strands and cables are compared with ultimate field values obtained on the magnets.