Derek asks this question about the procedure for isolating a solar photovoltaic (PV) system in a house, and whether it should be protected by a 32mA RCD. It has been answered by the ECA (Theme – Regulations and Legislation):
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Question: Could you please advise on the procedure for the isolation of a solar photovoltaic (PV) system in a house for which I have been asked to provide a quote?
The solar PV system installers have used an old shower circuit to feed the new consumer unit from the other side of the house, which - in turn - is controlled by a 32A MCB in a consumer unit having a 100mA RCD as the main switch and connected to a protective multiple earth (PME) system.
Should this circuit have an RCD protecting it?
Also, when installing the solar PV system, should the installers have upgraded the main protective bonding conductors from 6mm to 10mm (at the time of installation), or would their installation circumvent BS7671 when modifying the circuit?
What warning notices are they obliged to fit on the main supply consumer unit?
Answer: Subject to when the work was carried out, and what the consumer unit is serving, an RCD may have been required.
And yes, the main protective bonding conductor should have been upgraded at the same time.
Notices are required as detailed in BS 7671:2008 (2011).
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