Which switch is commonly used to switch the main electricity because it can isolate both live and neutral connections?

Which switch is commonly used to switch the main electricity because it can isolate both live and neutral connections?

• A. Two-way switch
• B. Dual on/off switch
• C. Resistor (nonvariable)
• D. Relay (relay switch)

Answer: (B)

To completely disconnect main power, you need a switch that can open both conductors: the live and the neutral. A dual on/off switch does just that by having two separate switches mechanically linked so both lines can be opened at the same time. This ensures there’s no path on either side of the supply, providing full isolation and safer maintenance or shutdown of the circuit. The other options don’t provide that full isolation. A two-way (SPDT) switch moves a connection between two outputs but doesn’t necessarily sever both live and neutral at once. A resistor isn’t a switch at all. A relay is a switch powered by a control circuit; while it can switch mains, it’s not the typical manual main-disconnect device intended to isolate both power lines in one action.

To completely disconnect main power, you need a switch that can open both conductors: the live and the neutral. A dual on/off switch does just that by having two separate switches mechanically linked so both lines can be opened at the same time. This ensures there’s no path on either side of the supply, providing full isolation and safer maintenance or shutdown of the circuit.

The other options don’t provide that full isolation. A two-way (SPDT) switch moves a connection between two outputs but doesn’t necessarily sever both live and neutral at once. A resistor isn’t a switch at all. A relay is a switch powered by a control circuit; while it can switch mains, it’s not the typical manual main-disconnect device intended to isolate both power lines in one action.