Normal switch ratings on a switch include the values of the maximum current and the maximum what?

Normal switch ratings on a switch include the values of the maximum current and the maximum what?

• A. Load
• B. Power
• C. Resistance
• D. Voltage

Answer: (D)

The key idea is that a switch has to be safe both in how much current it can carry and in how much voltage it can withstand across its terminals. The maximum current rating limits the current the contacts can carry without overheating or deteriorating. The corresponding maximum voltage rating defines the highest voltage difference the switch can safely interrupt and insulate against arcing or insulation failure. Power, which is P = V × I, depends on both voltage and current, but it isn’t a separate rating you’ll typically see on a switch. Also, “load” refers to the device being controlled, not a switch rating, and resistance can vary with temperature and isn’t a fixed rating either. So the maximum value described for safety and proper operation is the voltage.

The key idea is that a switch has to be safe both in how much current it can carry and in how much voltage it can withstand across its terminals. The maximum current rating limits the current the contacts can carry without overheating or deteriorating. The corresponding maximum voltage rating defines the highest voltage difference the switch can safely interrupt and insulate against arcing or insulation failure.

Power, which is P = V × I, depends on both voltage and current, but it isn’t a separate rating you’ll typically see on a switch. Also, “load” refers to the device being controlled, not a switch rating, and resistance can vary with temperature and isn’t a fixed rating either.

So the maximum value described for safety and proper operation is the voltage.