Who's rewired their house for this hobby?

Pete Turnbull pete at dunnington.plus.com
Sun Nov 23 19:46:35 CST 2014


On 23/11/2014 22:12, Brent Hilpert wrote:

> The benefit of the North American split-phase system vs EU/Britain is
> you have the energy & copper-efficiency of 240V available for heavy
> appliances, but you have the safety factor throughout the house of
> never having more than 120V between you and earth.

That's not as much of a safety factor as many people think, indeed 
possibly not at all.  It's true that 230V will give you more of a jolt 
than 120V, and more so because human body resistance drops slightly at 
higher voltages.  Nevertheless, there's a strong argument that a 230V 
jolt is more likely to throw you off the conductor whereas 120V may be 
more likely to make you latch onto it.  It depends how you touch it, 
obviously, but evidence suggests that (EHT excepted) the region around 
100V-130V is about the most dangerous.  I recall reading a discussion of 
that as part of the European harmonisation of voltages, in connection 
with 110V for site equipment.  Evidently that was in part why the idea 
of one live and one neutral with a single simple MCB or RCD was rejected 
in favour of the split 55-0-55 system (proposed by the UK).

-- 
Pete

Pete Turnbull


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