Switched neutral

Harry Macdonald:

This makes sense except that the electronics still sees the 230V when the device is switched off.

Also anyone who uses the light switch as a means of isolation before working on the contactor will find out the hard way why it is a bad idea. I would have thought that the regs should mandate a warning notice whenever this is the design.

If you are using a contactor, rather than a light switch, because either inrush currents or load currents are too high for the switch to handle, or you have alternative means of control such as SMART devices, then using the switch as a means of isolation for working on the contactor is at best a folly ... there will still be a live line conductor at the contactor ! I'd want to use an alternative point of isolation, such as the circuit protective device.

Harry Macdonald:

This makes sense except that the electronics still sees the 230V when the device is switched off.

Also anyone who uses the light switch as a means of isolation before working on the contactor will find out the hard way why it is a bad idea. I would have thought that the regs should mandate a warning notice whenever this is the design.

If you are using a contactor, rather than a light switch, because either inrush currents or load currents are too high for the switch to handle, or you have alternative means of control such as SMART devices, then using the switch as a means of isolation for working on the contactor is at best a folly ... there will still be a live line conductor at the contactor ! I'd want to use an alternative point of isolation, such as the circuit protective device.