Laser powder bed fusion (PBF-LB/M) is a potent technology for manufacturing demanding geometriesusing innovative materials. The complex thermal conditions during the process are nontrivial to describeand have a significant impact on final material properties. Therefore, these conditions are analyzed usingan experimental setup based on thermocouples embedded into the substrate plate close to the substrate-part interface of the respective sample. The in situ data allows for an in-depth investigation of correla-tions between core process parameters (laser power, scan velocity, exposed area) and the temperatureprogression at the base of the part. The alternative view on the conditions during the process enablesa novel analytical description of the thermal history. Additionally, a macroscopic FEM-model is pre-sented. It is calibrated and validated through the empirical data of geometric primitives to emphasizethe added value of the setup as a calibration tool for thermal simulations.