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T

tom262

hello all I've got to carry out some work at a ladys house who is suppoisidly sensitive to electricity, (just like the guy off "better call saul") anyway I'm planning to spilt the two ring mains to four radials and fit four "demand switches" which are meant to isolate the cables when there not needed, has anyone had any dealings with these switches as I'm about to order them online and at £160 each i don't want to buy them to find there is something better or cheaper that could be used. thank you.
 
I'm not doubting you or your client at all but a quick word of caution for anyone who reads this. There is a huge amount of hype and pseudoscience in the media about human sensitivity to electric fields, designed to play on peoples' fears of the unknown. It runs the gamut from guesswork and muddled thinking to outright charlatanism and fraud. Treat every piece of information and suggested method of protection against exposure with extreme scepticism, and make no claims for whatever you install other than that it meets electrical safety and functional requirements. Clearly, turning off a circuit when not in use is a much sounder approach than tying funny coloured stones to the cables, but this does not automatically mean there will be a beneficial effect on the person (other than as a placebo).
 
They would, but on the other hand these are almost user-transparent. A small sensing voltage is present on the circuit until load is detected, then this is removed and the circuit is energised with mains. The supply stays on until the load falls to zero again, at which point it is de-energised and the sense condition begins again. Like a load-seeking inverter or generator, the user theoretically doesn't have to do anything (unless tricky loads are connected which the controller can't sense.)

Light switches and contactors require the user to turn the circuit on before use and off afterwards, and they might not know when power is required or be available at the time to switch it on, e.g. appliances on thermostats and timers will require power at all times of the day and night.
 
Well regarding the human body and sensitivity to electric fields when I worked in the mines the favourate place to get warm/sleep if you could was on top of the transformer. If you listened carefully you could tell which machines started and stopped by the buzz it made.
Thats where the old joke about not been able to sleep at home without a bee in a matchbox at the side of your bed came from.

All studys seem to agree the higher the frequency the greater the risk( if indeed you believe in this) so its radio waves and microwaves etc. Oh and just googled to find out if the human body has a natural frequency some say 10 hertz some say 70hertz so consistant dribble.
 
...I think you all have a point,my grandad was told,as a boy,about the dangers of sitting in a house,with electrical energy fields surrounding him...and over the next 94 years...he lost nearly all his teeth...:conehead:
 
I have also heard stories about how electricity can harm the body etc..in fact I pulled out of a house sale after the buyers report showed that the property was surrounded by a few pylons (my wife was pregnant at the time) My personal view is that as an adult its not necessarily an issue, but im sure its not a good environment for young children developing. I wonder if in years to come they realise that wi-fi is terrible for us, similar to how we look back at the Victorians using radioactive face cream!
 

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