[en] The auxiliary heating at the TJ-II Stellarator consists presently of two ECRH lines with a total power of 400 kW and one Neutral Beam Injector of 32 kV H0, 400 kW port through power. During the last experimental campaign, the beam power absorption has been studied as a function of the plasma target profile in a variety of magnetic configurations. It was shown that the thermal energy content of the NBI plasmas is a factor two larger than at the ECRH plasma target, indicating a good power coupling to the plasma electrons. The density control is nevertheless difficult, the density rises rapidly from ECH typical values (1.1 x 10^-19 m^-3) up to 6.5 x 10^-19 m^-3, where a thermal collapse often terminates the discharge. A detailed knowledge of the gas and impurity sources associated with the neutral beams is desirable in order to improve the plasma density control. A well known source of gas and impurities are the beam-wall interaction areas. In TJ-II, as in other helical machines, the tangential neutral beam is partially intercepted at some points along the beam direction, typically by the toroidal field coil at the beam entrance and the beam stops at the beam exit. Knowledge of the power density distribution of the beam, as well as of its aiming direction is of the utmost importance in trying to understand the behaviour of the NBI plasmas. A retractable target calorimeter has been installed in a radial port next to the NBI port. The target consists of six CFC graphite plates mounted on a stainless steel frame, with thermocouples embedded into two copper blocks adiabatically mounted for calibration purposes. The target intercepts the beam at the duct exit, and the thermal print is observed with and infrared camera positioned below the beam duct, with a line of sight along the beam direction. Power density profiles in the vertical and horizontal directions can be obtained, as well as the aiming direction of the beam. The transmitted power can be studied as a function of the neutralizer gas, the injection direction, and the beam perveance. Therefore, optimization of the injected beams can be carried out '' in situ '', allowing even some customization according to different plasma targets and magnetic configurations. (author)