Can the LED on the 30PBL switch operate without a neutral at the switch?
Yes the 30PBL can be wired up so the LED will work. Unfortunately without a neutral there is only one method of wiring which will have the LED on permanently until the light is switched on then the LED will turn off. It is strongly Suggest you speak to you electrician as he will have the appropriate skills to achieve the function of the LED's. Some of the key features are:
Blue LED indicator
One way/two way switching facility with loop terminal
Retrofit option in to any 30 series aperture
Suitable for fluorescent loads Up to 16AX
Shrouded in-line Terminals provide protection during installation