Something to add, if you happen to have a small cut or open sore of any kind on your hand (or if you cut/stab yourself with whatever is high voltage) and the power makes contact with the bloodstream, it won't take much to stop your heart if theres a path.

 

yeah. nice.

voltage in a disposable camera capacitor!
http://forum.allaboutcircuits.com/showthread.php?t=10850


i've read that standard disposable cameras can deliver 500V at 120A.



further, though i'm not really able to totally verify the story, i've read about an incident in Sendai-shi Miyagi-ken, Japan, in which a student was killed by a battery-powered camera flash unit. an ACCIDENT which occurred due to lack of knowledge about the dangers. taking apart a battery-powered camera flash unit is actually pretty easy to do.

my point: that not all battery-powered circuits are safe,
still stands.

Perhaps you haven't noticed, but each and every one of what you linked to has been closed on this site. We still get them, and they still get closed.

Have you noticed that camera's using film are getting kinda scarce lately?

 

Hi all,

Thanks to all contributions in this thread. There is very much a discussion to be had on this subject and I am glad it has been opened up.

I will be having a chat with Rob later about this. In the meantime, please keep the comments coming.

Regards,

Dave

 

Perhaps you haven't noticed, but each and every one of what you linked to has been closed on this site. We still get them, and they still get closed.

i don't understand.
i posted links to one thread and it's certainly not closed.

Have you noticed that camera's using film are getting kinda scarce lately?

sure. on the new equipment shelves.
i've also noticed a wider variety of 35mm, medium, and large format gear on the used-gear shelves... + a stead dropping of prices. actually i picked up a decent flash unit for €2 a couple of weeks ago.
i'm sure not everyone has the urge to disassemble old electronics, but if they do, i'd sure hope that they observe some basic safety.

rather than issuing a blanket dismissal of the points i raised, i'd suggest the more useful (and perhaps respectful) approach of addressing specific comments and relate what you think is "bogus".

 

i don't understand.
i posted links to one thread and it's certainly not closed.

Do you mean the ones in this post: http://forum.allaboutcircuits.com/showpost.php?p=344554&postcount=20

Those are relatively ancient, dead threads. When new policies are adopted at AAC, it is rare that the moderators apply them retroactively to dead threads.

rather than issuing a blanket dismissal of the points i raised, i'd suggest the more useful (and perhaps respectful) approach of addressing specific comments and relate what you think is "bogus".

Given the rambling comments in your earlier threads, it is impossible to know which of them were not addressed. As I read comments related to them, I believe they have all been addressed.

John

 

Heres my plasma speaker in operation,
http://www.youtube.com/watch?v=vCI5RozQdTY
Which brings me back to my point of getting students interested in electronics. This little thing (along with my other stuff [nixie tubes]) got at least one of my friends interested in electronics. But, that being said, he's off ripping apart microwaves (which I warned him against) and trying to build a railgun. Fortunately he can't get anywhere on it without reading up, and is finding plenty of material on safety (along with all the links I gave him on the safety, including the one in the E-book). So I guess you could say that that door swings both ways.

Since he doesn't really have the know-how to build any one thing hes just jumping around taking about one step before meeting a wall, and jumping to another project. Plasma speaker to coilgun to railgun and etcetera.

 

Which is more lethal, AC or DC? Or they are just the same?

I think, I can only use the mains voltage after I mastered electricity or mastered its basics...

This has been discussed pretty thoroughly on other threads. Both at high voltage can be deadly. DC tends to make you clench, if you have your hands around a wire the electricity may make your hands grab and you can't let go. AC tends to make the heart defibrillate. So while there is minor differences it isn't really that important. You treat high voltages, when you have to mess with them, like fire. It can hurt you, but not if you are safe.

Beginners start with safer voltages and currents and work up.

Technology has changed at lot since I was a kid. Wall warts are a big improvement, when I wanted to build a DC power supply I had to buy an AC power transformer and work from there. Now I can buy a wall wart and go from there instead, so I advocate them for all beginners needing steady CD power.

AAC is a living site, it is evolving and changing. As technology changes so will the site in response. Now we have laser diodes that are in excess of 1W. This is a major blinding hazard as well as a burning one. Some of our members will eventually use them to make NC tables with, but you can bet questions about them will be closed, and casual experimentation discouraged.

If something like the eestor comes out we'll have even more rail gun threads that will get closed.

All this really means is people who want to do it will have to go to other threads. If something really bad happens they will be the ones being sued and shut down, not AAC.

 

All this really means is people who want to do it will have to go to other threads. If something really bad happens they will be the ones being sued and shut down, not AAC.

Case and point, 4HV

 

I hope AAC does not become like 4HV. There is some good stuff there, maybe depending on your perspective, but based on the first page of chemistry threads, there is even more wierdo/wrong stuff.

John

 

I hope AAC does not become like 4HV. There is some good stuff there, maybe depending on your perspective, but based on the first page of chemistry threads, there is even more wierdo/wrong stuff.

John

Me too, they are much less helpful/beginner friendly.

 

Heres my plasma speaker in operation,
http://www.youtube.com/watch?v=vCI5RozQdTY

like : )

Do you mean the ones in this post: http://forum.allaboutcircuits.com/showpost.php?p=344554&postcount=20

being the only thread i linked, of course.

Those are relatively ancient, dead threads. When new policies are adopted at AAC, it is rare that the moderators apply them retroactively to dead threads.

well closed or unclosed, the safety information is still valid.

Given the rambling comments in your earlier threads, it is impossible to know which of them were not addressed.

that's just argumentum ad hominem. and for Bill to say, "most of the comments here are bogus", does little to address specific points.

As I read comments related to them, I believe they have all been addressed.

or rather, waved aside as supposedly irrelevant.

to reiterate, i'm advocating the idea that general safety information should include notes on the potential dangers of SOME battery powered circuits... to make claims to a level of relative obscurity for such circuits does little to improve general safety and awareness.

 

Please, list the specific points you have raised that have been ignored or dismissed.

John

 

Again, you don't like the way it is done, you can always find somewhere else. This is not what this site is about. There are other places that cater to what you want.

We have had some very strange posts dealing with high voltages, scary ones, and some of those were young kids. I was especially impressed by the doorbell switch rigged for high voltage as a practical joke.

If you discuss how not to do something then there will be people who take that as a lead to do it, so we don't discuss it. I am advocating a set of rules on the subject.

Here are some past threads on the subject...

Things that close your thread

Safety Things That Will Get Your Thread Closed List

OK, where are we with automotive lighting and similar?

This is a subject where a lot of thought has already been put into.

 

Please, list the specific points you have raised that have been ignored or dismissed.

well, the quote "most of the comments here are bogus" serves to essentially dismiss most everything wrote here.

Most battery circuits do not involve high voltage. It is not something you do accidentally, and it isn't easy.

this is a specific dismissal. of course it's true that most battery circuits do not involve high-voltage... beginner projects would be naturally excluded from high-voltage. so yeah, experimenting with beginner kit-project, pretty safe... my concerns are generally directed towards people who may find tinkering with found electronics to be fun and educational.

it's one thing to adopt a policy of just saying "don't" and then leave it at that... at least you can always fall back on "i told you so".
however, a general, sober, and educational coverage of what the actual dangers are is just a safer route in my opinion.

 

well, the quote "most of the comments here are bogus" serves to essentially dismiss most everything wrote here.

At least we agree on something.

John

 

Perhaps I so fundamentally disagree with what you are stating that I feel it is an appropriate response. It is OK to disagree with someone, but when a casual statement about batteries and high voltage is made, knowing that they are closed as soon as they are opened, shows a serious lack of understanding of this site. I intensely dislike arguing for the sake of arguing. When this happens no amount of facts matter, I posted another thread about this not to long ago.

There is an exception made to these rules, when a level of understanding is present by the user, and usually the subject comes up with specific repairs. Occasionally we allow for hypothetical discussions, usually someone will post the appropriate warnings. In the end, however, it is up to the moderator. When I see a subject come up I feel is questionable I will flag it. Sometime the flag is ignored (which is to say, rejected). I may have a problem with that, but at that point it is over and not up for discussion. Most times I don't have a problem though, I just wanted a review of the thread.

This was brought up in my old thread, Things that close your thread. That thread brought out a lot of hostility, and a few people managed to get banned from over reacting. It goes back to it being the moderators call, which is a policy I support.

This site is unique in many ways. The ability to modify a post a year after it was made is unheard of anywhere else. I use the dickens out of it to write articles for the book, but it has been abused by people in the homework section to hide their questions after they have been answered. This has resulted in some minor rules changes. Like I said, this site evolves when it has to.

 

At least we agree on something.

oh good.
and since we agree on that, i'm sure you would also agree that such 'wave-of-the-hand' attempts to discredit a commentary are sloppy and condescending at best.

 

Well, that's enough of this thread. The original question was essentially answered in post #3 - the issue has been passed up to administration for clarification.

The subsequent posts have become more rancorous, and are not going to produce any useful outcome.

 

Just a quick feedback: there are a few things going on in the background which should be finalised in the next couple of days. As these things go public we will let let you all know and where necessary solicit feedback.

Once again I would like to thank everyone for their comments and suggestions. It is threads like these that allow AAC to change as the community changes.

Dave