Effects of the induction field on the ionospheric currents generated by the Sq dynamo were studied using current function. It was shown that the induction field significantly affects the ionospheric currents only if the field is artificially enhanced by 100 times. Existence of the spherical inner conductor reduces the effects because currents induced in the sphere partly cancel vertical component of the variation field. On the other hand, it is probable that the induction field should be considered for the simulation of the ionospheric current with the period of less than 10 min. because the induction field affects the ionospheric Sq currents if the field is enhanced by 100 times.