Interesting that this confusion actually continued through the early mini computer control panels. Mini computers designed in the UK (Elliot/Ferranti/ICT/Marconi etc etc) had address/data switches that represented logic '0' when up, and logic '1' when down. In the good old US of A of course this is reversed (DEC PDP11 etc etc).
With the hacked firmware on that, the 'redring' package allows some adjustment of the relative red and blue brightnewss, so that the (supposedly) purple when recording is more distinctive.
When Cable & Wireless outsourced the regional business IT support group to Sema Group in Kings Cross, the building had all telecom services supplied by Colt.
In the basement of the office block where we were located was a Colt fibre optic termnation box fed by a 3-pin plug and socket.
One Friday someone unplugged this box at about 2PM to use the socket for some other purpose. The box had an 8-hour battery backup and the Colt engineers at the nearby BT exchange (where they had an office) watched the power fail messages for 8 hours until the battery died but never phoned up to ask if there was a problem !!.
later that weekend a couple of the Caribbean business units suffered software failures on their local Vax/Alpha systems and couldn't run vital backups, batch jobs and billing runs. The person on call in the UK couldn't dial in to the VMS system in this building to fix the problems, and all the phones were dead, so no managers could be contacted. Lots of very angry users and 'managers' the following week.
I could barely resist the tempation to ask one particular bullshitter why this vital bit of kit wasn't connected to a fused spur with no on/off switch.
Minis and 1100's tended to leave their ignition key in the drivers left kneecap
But these are mostly used for monotering a persons condition or giving a life saving drip or some other medical treatment, you don;t wan tthat switching off because a cleaner hit the swtich with their elbow or anything else.
I noticed that on the opollo misions many of teh switches had guards over them but didn;t notice whether this was to protect them from being switched off or on up or down.
I doubt that is a main reason as most the the equipemtn has a means of doing something with the plug end.
Either. It was hardly graceful trying to move in a sodding big suit ...
The ones I have fitted don't energise the pins until you rotate the bulb into place. This means that even pushing with a finger is safe. For example, MK 1150WHI.
It's not just me, then. And they're half behind the steering wheel as I have it set quite high.
That's a Schuko socket as used in large parts of Europe. It was unlikely to be French writing though, because the sockets used in France and Belgium have an easrth pin centered above the live and neutral sockets.
Can be a bit of a pain with old unearthed plugs because they didn't have a hole for the earth pin to enter!
Appliances these days come with moulded modified Schuko plug.
As well as the side eathing contacts, they also have an earth socket to fit French sockets.
I would guess it was what the original manufacturers in each country decided to do.
If you take the UK, by the time many people started visiting foreign parts, virtually everyone had switches following that countries convention.
I visited Northern France and Belgium with a friend in 1972. He asked me why he couldn't plug his electric razor in, so I went to his room as he demonstrated that the pins only went into the holes about a mm or so.
When I looked at the round surface mounting socket on the wall, the pins of his UK 5A 2-pin plug neatly fitted the screw fixing holes but not, of course, the other two holes for the live and neutral pins of a French 6A plug!
MK is usually good stuff. I've not seen those, but, there again, I haven't bought any lampholders for some years.
SteveW
I was talking about switched sockets generally, rather than just in hospitals, but anything that needs to keep running in a hospital has its own battery - monitors, syringe drivers, etc. and they'll start to alarm well before the battery gets too low.
Possibly different for different switches? Some you might not want to accidentally knock on and some might need to be kept on?
Again, I was referring to plugs and sockets in general.
SteveW
Yes they should be left plugged in so they fully charge just in case anything does go wrong. They only have a limied backup time, so they should be plugged in all the time, similar to a UPS for a computer.
Yes, but it had little to do with up or down as in space there's no real up or down or gravity. And didn't one break on Apollo 11 and they had to use a pen as a temporary fix.
Would this be on the missions that came after the disaster that nearly befell Apollo 11?
One of the astronauts' bulky back packs smashed a contact breaker on the LEM that provided power to the ascent engine.
If they hadn't managed to fix it, they would have been stranded on the moon.
Fortunately, Aldrin had a felt tipped pen with him and was able to jam it in the breaker and operate it.
At installation time, you should check if they are all in the off position, the circuit is off. Doesn't everyone do this? ;-)
When the GPO (as it was then) engineers were commissioning the trunk network for a 22 channel cable network for The Stock Exchange in 1969, they kept visiting buildings to find no incoming signals.
As the system wasn't live there were no helpful phone calls to help identify the source of the problem so they had no choice but to trudge round the City's streets with their kit - which included a particularly heavy LMS (I know - we had one as well!) - visiting each building along the trunk until they found the problem.
The power was fed on unmetered feeds via switched fused spurs.
What would happen was the the housekeeper, who lived in a flat in the building, would make a routine inspection when the building was empty and spot the neon on the spur. Obviously nobody could be using it, so they simply switched it off!
Stock Exchange electricians had to visit every building and swap out the switched spur for an unswitched one to stop it happening?
Concorde cockpit had loads and loads of them. Didn't think to ask if down was on.
Down is for landing, up is for take-off obviously. :-)
Probably not when just replacing a bulb...
Good thinking, Batman.
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