One safety attribute here in the US, which I frankly find annoying, is the ubiquitous twin blade plug, with the one "widened" blade, that assures neutral is neutral, hot is hot.
Even on my "double insulated" hand-held plastic bodied machine tool; kitchen or workshop. What, does the blade/bit have a greater probability of getting AC line energized in a fault if one particular wire isnt "neutral"? Only adds to the "180 deg out" difficulty I find plugging in, when you dont have a direct eye shot at the socket.
Leave that feature to the three wire plugs - or make everything a 3 wire plug by law.
I had some fun at work... The building I work in is roughly WW2 vintage, late 40's. We recently had an issue with steam pipes and transformer vaults, took the building power down. For some reason, 2400 to 480 volt transformers do not like being immersed in steam..go figure.
In the interim, I asked about building grounding to protect against faults.. As time rolls on, electrical service marches on, such that attached buildings can have service provide from another building. I was worried about the integrity of the fault return paths should one occur. One concern is, should a fault to ground occur with a 30 kiloamp supply, what grounding ampacity is required??
Granted, most of the issue is with 480 volt service, 600 amp being typical. But over the years, did anybody consider the fault return path? Obviously, the answer is..if so, they are dead now..
As a result of my question regarding this, I googled the national electric code. It started in 1896 (IIRC), and was established in 1910 (IIRC) by insurance guys, firemen, and electricians to prevent fires.
The wide neutral blade is a good thing. But, I trust nothing.
Double insulated is a good thing, batteries are better in my view.
John
In the interim, I asked about building grounding to protect against faults.. As time rolls on, electrical service marches on, such that attached buildings can have service provide from another building. I was worried about the integrity of the fault return paths should one occur. One concern is, should a fault to ground occur with a 30 kiloamp supply, what grounding ampacity is required??
Granted, most of the issue is with 480 volt service, 600 amp being typical. But over the years, did anybody consider the fault return path? Obviously, the answer is..if so, they are dead now..
As a result of my question regarding this, I googled the national electric code. It started in 1896 (IIRC), and was established in 1910 (IIRC) by insurance guys, firemen, and electricians to prevent fires.
The wide neutral blade is a good thing. But, I trust nothing.
Double insulated is a good thing, batteries are better in my view.
John
When I worked at AMZN, all the conveyor control cabinets ran off 480. The rule was, if you opened the cabinet doors or any enclosure with 480 in there, you had to wear the full arc flash protection suit with the double gloves. Attach a serial cable to the PLC? Full suit. Vacuum the dust out of the control cabinet bottom once a month? Full suit. Work on anything > 48V? Full suit.
Lots of internal stories, lots of NEC training videos to watch. Like the one where this guy - unprotected - plugs in one of the glass housed watt hour meters and you see the whole video frame just turn bright white. Or the story of what happens when someone tries to measure 4kV direct from the pole with their DMM. Or a similar fatality when someone tried to measure 12kV also with a DMM...
I measured 480 VAC power with a DMM probe once. The double gloves are so cumbersome, they actually increase the risk of a slip of the probe tip. Glad to never have to touch such a thing ever again in this lifetime.
The turning point came in the late 1960s/early 1970s when bosses became legally responsible for workplace deaths.
That's one difference between the Netherlands and other countries I have visited: except for the real high-voltage lines (like 150 kV and 380 kV) and the lines used for trains and trams, there are almost no overhead power lines here.
Yes. At least in Germany, there was a huge push in the mid 80s to remove those. My parents had one large concrete pole right in their front garden, surrounded by Nordmann first, which raise to a couple of dozen meters in height. Every couple of years, local energy company sent some guys to cut them down a bit, to keep a safe distance to the lines. Those were like 30kV I guess.
In the 80s, they went "all cable" for the mid voltages and removed the poles, including the huge blocks of concrete. In the 90s they removed the even larger ones (110kV?) in our area, leaving only the really ones.
The newly built intra-country-connects are now even partly earth-bound, therefor quite expensive. But some folks in southern Germany insisted on it, by delaying the construction for a good decade. Northern folks (probably the same for the Netherlands) are getting used to all those wind turbines and high voltage lines 🙂
With respect to the Bush DAC90 being "safe": it is possible that the bakelite enclosure provided what we would now call reinforced insulation. I'm thinking that Bakelite could withstand the 4kV test. Not sure if the IEC pin wouldn't touch the chassis in some places however. And then there would be the "impact" tests that the bakelite might have failed as well. What I'm thinking is that the "hot" chassis wouldn't necessarily violate safety requirements if the case really provided proper insulation. Also, it doesn't sound like there was a set of safety standards that the radio would have been subjected to. When those standards did come about, engineers would have decided that the "hot" chassis had too many drawbacks to overcome.
I found this, which uses Health and Safety Executive (HSE) statistics relating to the workplace:
"On average (using HSE figures 2008-2018) just less than 5 people die as a result of electrocution each year."
However, I'm not sure whether those figures are incidences of actual 'electrocution', or include death due to 'electrical injuries'.
More interesting facts are in the link: https://elecsafety.co.uk/the-risks-in-underestimating-the-danger-electricity-poses-in-the-workplace/
Yes, the meaning of 'electrocuted' has been degraded.
Even Wikipedia talks of death or severe injury so the proper English meaning is being, or has been, lost.
Hot chassis were used for television until well in the 1980's. The advent of SCART connectors ended that.
There are two types of wall socket in Europe.
Yours will be the dual side contact earth type and will be reversible.
There is also a round pin earth type that is non reversible.
Appliance cables have both earth contacts on them so that they will work in all of Europe.
https://www.plugsocketmuseum.nl/Schuko1.html
https://www.plugsocketmuseum.nl/French1.html
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I was unfortunate to be present when a fatality due to electrocution occurred. I was installing a main frame computer and some
Post Office engineers were installing a computerised telephone exchange in the same room. In those days anything to do with the
telephone system had to be done by The Post Office. This could well have saved my life.
I cant totally remember what happened but it was to do with the 3 phase supply being incorrectly wired. What I do still remember
is the sound of someone being electrocuted, I'm grateful though that I didnt actually see it happening.
Needless to say I've been very very safety conscious since.
Post Office engineers were installing a computerised telephone exchange in the same room. In those days anything to do with the
telephone system had to be done by The Post Office. This could well have saved my life.
I cant totally remember what happened but it was to do with the 3 phase supply being incorrectly wired. What I do still remember
is the sound of someone being electrocuted, I'm grateful though that I didnt actually see it happening.
Needless to say I've been very very safety conscious since.
Came close one time in a reliability test lab. Large, overhead rectangular conduits hung every 6' or so; you'd clip on a metal box with the breaker and wiring for whatever service was needed. There literally was this random box; I think it was painted red, no one knew how it was wired, but it seemed to have the sockets needed.
One coworker plugged it into the bus, upon which a shower of sparks ensued. He went to the nurse directly, as it appeared a small chunk of his thumb got blown off. The lead engineer of the project (a Q-Bus to ethernet adapter) said he'd never seen an arc as big like that.
I think it was arcing between the box metal retaining screw and the metal housing of the conduit; luckily the guys hand didnt make contact before the metal did, or current didnt travel across his arms. Sometimes you could just push the box in place with one hand, sometimes you had to put your other hand on the back side of the conduit, depending on how stiff it was hung where you happened to be along its length.
I'll guess that happened sometime in the mid 80s. These days there'd be a lot more paperwork to fill out over such an incident. I think the fellow got his hand cleaned up and bandaged by the nurse and that was it. Today if they fired him over it, he could sue the company, claim no training was given for the work to be performed - and win.
Back in the days when I was a very keen flyfisherman rods were made from baked bamboo strips glued together. The more modern carbon fibre
rod came along and was seen as a preferable material by many. However it was not long before serious electrical burns and even deaths were
reported, The trouble came when in damp conditions electrical current would arc between these (high conductivity) carbon rods and nearby power lines. Some of these arcs resulted in very severe burning and even death whereas to accidentally touch an exposed mains wire with a CF rod was usually fatal. [Many rod makers applied vivid warnings near the cork handle of these rods, but that seems to have ceased some years ago]
I usually fished rivers in the NW Highlands or Outer Hebrides. Though there is a paucity of overhead power lines there are a few...but the other danger is a Lightening Strike. Of course the CF rod in your hand is an invitation to the lightening to come and get you! The only sensible thing to do is to drop your rod and get back to your car / lodge as fast as you can...leaving your rod behind to be collected later. This has often happened for me and there is the added benefit of a comfortable chair and a whisky to pass the time until the storm has passed.
rod came along and was seen as a preferable material by many. However it was not long before serious electrical burns and even deaths were
reported, The trouble came when in damp conditions electrical current would arc between these (high conductivity) carbon rods and nearby power lines. Some of these arcs resulted in very severe burning and even death whereas to accidentally touch an exposed mains wire with a CF rod was usually fatal. [Many rod makers applied vivid warnings near the cork handle of these rods, but that seems to have ceased some years ago]
I usually fished rivers in the NW Highlands or Outer Hebrides. Though there is a paucity of overhead power lines there are a few...but the other danger is a Lightening Strike. Of course the CF rod in your hand is an invitation to the lightening to come and get you! The only sensible thing to do is to drop your rod and get back to your car / lodge as fast as you can...leaving your rod behind to be collected later. This has often happened for me and there is the added benefit of a comfortable chair and a whisky to pass the time until the storm has passed.