Discuss 18th edition question in the UK Electrical Forum area at ElectriciansForums.net
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with a fault current of 115A, what do you think will trip i 200mS or less?
300mA , but somewhere I recall BS7671 or a GN recommending 100mA for a TT installation ( presumably to allow for variations in the Ra)
Is that actually a genuine 18th Ed question or something from online.
now that is interesting. the bit about insulated and sheathed cables meeting the requirements of double or reinforced insulation.
nope. you'd have 30mA for final circuits. if you had a 30mA for fault protection, that would contravene the division of circuits and discrimination of RCDs in series.
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