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12
Consumer Unit Arrangements
Not Permitted
A consumer unit with a 30mA RCD main switch would not be suitable
for 3 main reasons:
• The Fire detection circuit and the socket outlet circuits share a
common RCD. This could reduce the reliability of the mains supply
to the Fire detection circuit as appliances and portable equipment
are likely causes of RCD tripping.
• The cumulative effects of electronic equipment in the modern
home, is such that some current is likely to flow in the protective
conductor. A 30mA RCD will trip between 15-30mA. This could
cause unwanted tripping, regulation 314.1 (iv) refers.
• Any fault would result in the loss of all the lighting, this could in
itself cause a hazard and the lack of power to the fridge/freezer
circuit for example would be very inconvenient. Regulation 314.1 (i)
asks the designer to consider this eventuality.
An example is shown over page.
A consumer unit with a
30mA RCD main switch
should not be used to
protect all the circuits
“
”