Why are power duty switches not suitable for use with pilot duty loads?

Power duty switches are designed to handle heavy electrical loads, which generally involve high current and substantial mechanical pressure in their contacts. When it comes to pilot duty loads, which are usually lower current devices such as control circuits or relays, the contact pressure generated by power duty switches may not be adequate for reliable operation. This lower pressure can cause issues, especially in conditions where surfaces might be dusty or oxidized, leading to poor electrical connectivity. As a result, the insufficient contact pressure can prevent the effective operation of the pilot duty loads, making them unsuitable for these applications.

In contrast, the other options, while they may touch upon other aspects of electrical equipment, do not accurately reflect why power duty switches are specifically incompatible with pilot duty loads. For instance, heat generation, compatibility with DC or high-voltage systems, while important considerations in electrical engineering, are not the core reasons for this particular incompatibility related to pilot duty applications.