Abstract <p>The paper discusses some features of direct measurements of the magnetocaloric effect in alternating magnetic fields. Various regimes of the magnetocaloric effect manifestation in alternating magnetic fields under different external conditions are simulated. The models account for the degree of deviation of the system from adiabatic conditions, different thermal response time of the sample–thermocouple system to an alternating magnetic field, as well as combinations of these conditions. The limitations of measuring methods of the magnetocaloric effect in alternating magnetic fields due to their peculiarities are considered in detail.</p>