Why....

Nov 20, 2019 Last reply: 6 years ago 80 Replies

No which brings us to lamp holder safety, both bc and es devices present the live terminal to within easy reach of a finger or two.

It is a very weird sensation getting a shock this way, lets just say you are left in no doubt about it being low frequency AC!

Brian

Pretty certain there was some convention for switches in equipment subject to vibration that the position a switch was most likely to fail in was down - so the "down" position became the failsafe. Aircraft and cars being the first things that spring to mind.

All circuits are live until proven otherwise.

Many years ago, I found a switched mains socket, which seemed to be two pin but had a circular area with earthed metal top and bottom. It meant that you could mount it either way up and it was still the same, Admittedly the live was on the other side, unless you wired it to suit of course, in which case the switch was merely on the other side. Interesting design, but do not know from what part of the world it hailed. It had some embossed writing inside that looked French to me at the time. Brian

I think you mean they all show red on /Standby/, not "off".

Actually the standby colour is orange, matching the display (which is a white VFD behind an orange filter).

I've never had a problem distinguishing the orange from the red.

Yeah and Japanese switches go side to side because of earthquakes or something.

The model HDR-2000T 1TB has no other display, and no orange mode, at least as I perceive it.

Chris

But eartthquakes also go side to side

American fail safe so switches don't get knocked down and on by accident......very unusual to knock a switch up by mistake.....

A grand designs program of 15 years ago showed an art-deco timber framed hoouse in Surrey (self-built decades previously and now with advanced timber rot) demolished and replaced by one of theose german Huf houses. The sockets fitted to the kitchen had their rocker switches above the socket and operated from side to side.

My fathers house which was built in 1956 on land to the side of the bungalow where we lived, still has all its original black bakelite toggle switches.

My Amptastic amplifier has one of those nasty blue leds, but the instructions show you how to open the casing and remove the plugin connector to isolate it.

BT Smart hubs allow you to set the brightness level and set a daily time window when the blue light will be extinguished.

Also the era when people arrived in A&E after a head on RTA with classic injuries caused by projecting switches and keys.

Many. A&E staff could guess quite accurately what make of car the victim was driving before seat belts became mandatory.

Perhaps logic is the reason.

But what about the switches on sockets.

Here in my lab we have centre off rocker switches, press them down and the light comes on, press them up and hold the light dims, a brief press up and the lights go off.

I noticed that a lot of the wall sockets for 3 pin plus in the local hopstital don't have switches, I was told it;s because switches are easy to accidetnly switch off, so why have something plugged in and switched off, perhaps isn't logical.

Up for on is normal in many other countries.

So is driving on the wrong side of the road ;-)

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