I've volunteered (!) to install a complete theatre lighting system in my local sports hall, so the stage can be used for theatrical productions, bands and so on. It should be fun.
Part of the deal is that the new system is to be completely independent of the existing installation.
It will be fed from a new Hager three phase board, with RCBO circuits going out to the amps, stage rack, various lighting trusses and so on. The board will be at the rear of the hall, where the stage snake and other infrastructure will terminate for the audio and lighting control desks.
A 5-core flex, either from elsewhere in the building or an external generator, will be used to energise the installation only whilst it’s in use. It’s analogous to a mobile studio with an appliance inlet on the side.
Here’s the question: there’s no easy route from the new board to the building incomer. Do I need to earth the installation separately, or can I rely on the inlet earth which of course will be present only when connected?
I’m guessing the whole thing becomes extraneous metal parts when not connected to anything?
Part of the deal is that the new system is to be completely independent of the existing installation.
It will be fed from a new Hager three phase board, with RCBO circuits going out to the amps, stage rack, various lighting trusses and so on. The board will be at the rear of the hall, where the stage snake and other infrastructure will terminate for the audio and lighting control desks.
A 5-core flex, either from elsewhere in the building or an external generator, will be used to energise the installation only whilst it’s in use. It’s analogous to a mobile studio with an appliance inlet on the side.
Here’s the question: there’s no easy route from the new board to the building incomer. Do I need to earth the installation separately, or can I rely on the inlet earth which of course will be present only when connected?
I’m guessing the whole thing becomes extraneous metal parts when not connected to anything?