The powering systems of the CMS tracker for HL-LHC

The upgraded CMS tracker for HL-LHC is going to require more than 200 kW power. Two different powering strategies are being adopted for the Inner Tracker and the Outer Tracker. The talk describes the two powering schemes and discusses their intrinsic constrains. Specifications for the powering units and for the cables of the two systems are outlined in combination to preliminary results with prototypes.