True enough, unless it's TT supply, even then it's probably not a
*legal* requirement just a Very Good Idea.Pretty sure the latest regs require that any circuit that isn't buried > 50 mm from any surface or mechanically protected (earthed steel conduit or similar) has to be RCD protected. Be that RCBO's on each circuit or an RCD protecting several circuits.
No, but an unlucky few did.
As has been pointed out before, keeping you alive is only one of many reasons that RCDs are a good idea. The death rate from electric shock directly is low enough that you can probably discount it as highly unlikely. The 200,000 admissions to hospital each year treating the effect of electric shock however should make even stupid/brave people such as yourself, take notice. Projections of a reduction of 4000 house fires per year have also been put forward as a likely result should those properties currently without RCD protection be upgraded. (in 2011 there were 8,900 non fatal house fire casualties, and 306 fatal ones)
Indeed, although unless its a property with TT earthing, there is no need for the type S upstream RCD.
Which I why I just gave one (and there are several options)
in 16th edition days that was mostly true...
On Thursday 22 August 2013 00:21 Dave Liquorice wrote in uk.d-i-y:
They do.
Wiring to the 17th needs 30mA/40mS RCD protection of all circuits with only special case exceptions - the sort of exceptions you will almost never see in a house.
Not much you're not...
8900/65000000=0.01%.
Another option, don't forget, is to use a double-wound isolating transformer, followed by a local RCD on the secondary side. Earth one side of the secondary (or a centre tap) before the RCD. Earth leakage is then confined to the secondary side and there can be no residual current in the primary circuit (other than a small amount due to stray capacitance) to trip the upstream RCD.
Of course if the machines concerned require more than a kVA or two this will get impracticably expensive and heavy, and with a big transformer there's the risk that its primary inrush current at switch-on will trip an upstream MCB...
+1. Anyway Darwin Awards may get him soon.
Not at all.
But you have ever been to a house where a customer could feel an electric "tingle" from a fish pond and then announced "the deeper you stick your arms into the water the bigger the shock"?
Why would that concern you? If it's mild enough that they are fine with pushing their arm in further, then it's not a large amount of electricity.
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