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• A custom built device to directly measure Δ T was designed, and its running frequency is up to 9 Hz and temperature span between about 235 K and 313 K. • The relationship between the temperature change of Gadolinium and alternating frequency of magnetic field under the near working condition can be directly obtained. • The theoretical model was built to investigate the effects of different influencing factors on the temperature change for MCE materials. In magnetic refrigerator, the magnetic induction and its alternating frequency have great influence on the magnetocaloric effects of materials. In order to relationship between the magnetocaloric effect and alternating frequency of magnetic field, the direct measurements of temperature change for Gadolinium near working conditions in alternating magnetic fields up to 9 Hz are carried out. In this device, the magnetic field is alternately changed by rotating the magnet while sample holder keeps stationary to defend the measurement signal interference. Results shows that the temperature change of Gd decreases from 1.5 K to 0.7 K with increasing field alternating frequency from 2.2 Hz to 9 Hz under magnetic field of 0.72T. Furthermore, based on the heat transfer process between sample, thermocouple and environment, we have established a theoretical model to investigate the effects of different influencing factors on the temperature change of Gadolinium. It reveals that near work conditions, there are lots of influencing factors to affect the temperature change, such as sample mass, applied magnetic field mode, adiabatic conditions, cycle frequency, and so on. The experimental and simulation results provide the guidance for screening the best candidate of magnetocaloric materials and developing the magnetic refrigerator. [ABSTRACT FROM AUTHOR]