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Electrical matters: Regarding the use of loads, there is a significant difference in the operating capacity of push-button switches between AC and DC circuits; please check the rated values. In DC applications, the control capacity is very low. This is mainly because direct current does not have a zero point (a point where the current crosses zero) like alternating current; as a result, once an arc is formed, it is difficult to eliminate, and the arc persists for a long time. Moreover, since the direction of the current remains unchanged, contact migration occurs; the contacts cannot be disconnected due to their uneven surface, which may lead to malfunction. For some types of loads, the constant current and the inrush current differ significantly. Please use it within the allowable surge current range. The greater the inrush current during shutdown, the more wear and migration occur at the contacts, which can lead to failures where the contacts cannot be switched on or off due to welding and migration of the contacts. In the presence of electric induction, a reverse induction voltage is generated; the higher this voltage, the greater the energy, and as a result, the wear and migration of the contacts increase. Therefore, please verify the rated conditions – the control capacity is indicated in those ratings – but this alone is not sufficient. In special load circuits such as those with voltage/current waveforms during switching on and off, as well as different types of loads, actual equipment testing must be carried out to confirm the performance. ?For applications involving small voltages and currents, please use products designed for light loads. Using general-purpose silver contacts may lead to reduced contact reliability. For miniature and high-load button switches that exceed the normal range of button switches, connect a relay suitable for that load. The conditions for determining the rated values of each model are as follows. Inductive load: Power factor of 0.4 or higher (AC), time constant of 7 ms or less (DC). Lamp load: A load that has a inrush current equal to 10 times the constant current. Motor load: A load with a surge current equivalent to 6 times the constant current. Note. Inductive loads are particularly important in DC circuits; therefore, it is essential to fully understand the value of the load’s time constant (L/R).