I have a Client that will not provide a Risk Assessment to omit an RCD Commando Socket for a Data Cabinet. He wishes to employ a local isolator for the Cabinet, however he is concerned that the PDU Strip that arrived on site from the factory and pre-fitted within the data cabinet would still need an RCD. It is my opinion that the Factory built Data Rack is classed as a piece of equipment and as such does not form part of the Contractor's installation. If the Rack had arrived on site without the PDU strip fitted and it was installed by the Contractor then this would form part of the installation and therefore would require an RCD. Any advice/assistance would be appreciated.
This does bring out a point from BS7671, which is the blanket requirement for RCDs for sockets up to 32A. In an installation such as this with supplementary bonding to earth, the RCD has exactly zero use! There is no shock risk unless the equipment is opened and live terminals accessed, whatever earth fault occurs. This point needs revision, because it simply doesn't make any kind of safety sense. From your point of view I suggest fitting 63A BS4343 connectors to the installation. If they choose an RA, it is fairly straightforward, the environment is controlled and nothing else may be plugged into the socket, and the supplementary bonding must be in place and tested (notice) before the equipment is energised.
This does bring out a point from BS7671, which is the blanket requirement for RCDs for sockets up to 32A. In an installation such as this with supplementary bonding to earth, the RCD has exactly zero use! There is no shock risk unless the equipment is opened and live terminals accessed, whatever earth fault occurs. This point needs revision, because it simply doesn't make any kind of safety sense. From your point of view I suggest fitting 63A BS4343 connectors to the installation. If they choose an RA, it is fairly straightforward, the environment is controlled and nothing else may be plugged into the socket, and the supplementary bonding must be in place and tested (notice) before the equipment is energised.
