Electronic – Switched neutral option in switch datasheet

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Looking at this datasheet for a mains switch, the 'preferred option' (5503 on the sheet) is called 'switched neutral'. I cannot see how both the live and the neutral can be switched with only 3 pins, as surely you need four (two for input live/neutral and two for output live/neutral) which leads me to believe that only the neutral is switched in this arrangement.

I also don't see how the circuit diagram makes sense, as if the mains plug is connected to pins 2 and 3 then this should just give a short across them when the switch is closed. If instead the mains plug is connected to pins 1 and 2 then only one of the live/neutral can be switched (depending on which one is connected to pin 2).

As only switching the neutral sounds like a terrible idea, combined with the lack of understanding of the circuit diagram, this leads me to assume I have misunderstood something quite badly. Any help you could give me in this matter would be greatly appreciated.

EDIT: The only way I can see the switch working properly is if we have the following setup:

      Pin 1          Pin 2         Pin 3
       (*)            (*)           (*)
       / \             |             |
      /   \            |             |
     /     \           |             |
    /       \         live          live
   /         \        mains         circuit
  /           \
neutral    neutral
mains      circuit

as when the switch is closed pins 2 and 3 become continuous. This seems to disagree with the answers below, where pin 2 is the common neutral pin. Have I misunderstood the answers as well as the datasheet?

Best Answer

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Left goes to mains, middle to your appliance, right goes to ground (maybe via a resistor??). The difference between 5503 and 5508 is that 5503 disconnects both sides of the lamp when off, while 5508 keeps the ground side connected. So the '(un)switched neutral' refers to the neutral of the lamp only.

I don't see the purpose of the 'disconnect the lamp's neutral': the other side of the lamp is still connected to the neutral via the load, so for safety purposes it is still connected.

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