What is the maximum ON/OFF frequency of a solid-state relay (SSR) for DC loads?

The maximum ON/OFF frequency of a solid-state relay (SSR) for DC loads is often determined by the internal characteristics of the relay, including the switching speed and the heating generated during operation. Solid-state relays are designed to switch faster than electromechanical relays because they do not have moving parts, which allows for higher frequency operation.

In many typical applications, a maximum frequency of around 100 Hz is feasible for SSRs handling DC loads. This allows the relay to operate effectively while managing thermal constraints and ensuring reliable switching without excessive wear or failure. The choice of 100 Hz represents a practical upper limit for effective performance in common SSR configurations, making it the correct answer in this context.

The other frequency options provided do not align with the typical capabilities of solid-state relays. Frequencies such as 50 Hz, 10 Hz, and 90 Hz do not reflect the maximum operational limits of these devices, especially for DC applications where faster switching is advantageous. Thus, focusing on the capabilities of SSR technology, 100 Hz stands out as the most appropriate maximum frequency for DC loads.