Talk:High-voltage hazards
Administrative note: I deleted the original version of this page, which was just a redirect, and then renamed High-voltage differential to become this page. I doing so, I destroyed the history for this page. Just for the record, the lost history contained only two entries: the first was the creation of the article by Reddi, and the second was a minor edit by me. -- Heron 12:29, 2 Aug 2004 (UTC)
Arc welding
[edit]The article says that voltages below 500 volts can't produce an arc. However, electric arc welding sets typically have an open circuit voltage less than 50 volts, and anyone who's seen one in operation can testify to the very bright sparks produced. This needs a re-write, I think. --Wtshymanski 23:16, 6 May 2005 (UTC)
The key word is "produce." Take two wires from a 500V supply and move them together. No spark appears until they're a fraction of a millimeter apart. A 500V supply doesn't produce significant sparks. Now try a 20,000V supply and a spark appears even when the wires are separated by many millimeters. But if you separate the wires once a spark has appeared, all bets are off. In that case the spark length is more determined by wattage and by the metal of the wire tips rather than voltage. --Wjbeaty 09:56, May 7, 2005 (UTC)
- It wasn't apparent to me that the article was talking about breakdown of air as opposed to all the other ways electrical sparks get initiated. I guess I know how to fix that...--Wtshymanski 15:58, 7 May 2005 (UTC)
Buried Cables
[edit]Several types of cable are approved for direct earth burial in the Canadian electrical code that are not armoured or metal-sheathed. Neither metal sheathing nor armour provides complete protection from electric shock hazards to unwary diggers - for that matter, even a concrete duct bank can be penetrated by a determined jackhammer operator. Yes, the excavator operator may survive the inital contact because he's usually sitting in a machine isolated by rubber tires from the ground; the previous language in the article was baffling to me and so I've revised it. --Wtshymanski 16:44, 11 July 2005 (UTC)
Spam
[edit]I removed the link to SafetySmart as it is not an informative site. It is a company selling HV saftey services.
Lightbulb
[edit]It is stated that 500J can power a 100W lightbulb for 2 months. That's way off: 500J can power a 100W lightbulb for 5 seconds... changing to 500MJ which is about right (it actually takes about 518MJ, but...)
Choice of standard voltages?
[edit]Why choose odd voltages like 11kV, 33kV and 66kV rather than round voltages like say 10kV, 20kV, 30kV, or 60kV?
Tabletop 02:17, 29 September 2006 (UTC)
GA
[edit]This is a very good article and I would like to thank all who have contributed. It is very very interseting to read. Penubag 03:52, 1 May 2007 (UTC)
Definition
[edit]The definition here is confusing. There is a bit of waffle about how you define the definition but at the end of the day high voltage is 1000V (AC) as defined by the various standards agencies. I am not so sure about DC though and will investigate a bit further. The entire definition section should be only a couple of sentences. I would like to change this and ask for any comment first. Lumberjack Steve 12:33, 7 July 2007 (UTC)
Can anyone here provide even a single authoritative reference that describes normal household mains voltage (100–240 V AC) as "high voltage"? This currently claimed usage seems rather naive and unusual to me and I would have thought that even most lay people would associate with the term "high voltage" something that one would normally express in kilovolts. Markus Kuhn (talk) 18:51, 9 February 2008 (UTC)