nanog mailing list archives
Re: Why choose 120 volts?
From: Steve Bertrand <steve () ibctech ca>
Date: Tue, 26 May 2009 18:43:36 -0400
Barney Wolff wrote:
Getting back to reality, I've watched more than one electrician do a two-finger liveness test on a 120v circuit, and done it myself. 240v HURTS, and I've not seen a pro finger it deliberately. But I haven't actually asked.
During my residential electrical apprenticeship, one of the tricks of the trade I learnt was a quick two finger test on 120, but never anything higher than that. That was years ago. I would never do anything of the sort intentionally ever again, even on low voltage systems (my girlfriend is an Occupational Health and Safety Officer, and she frowns on that sort of thing ;) It really depends on your conductivity to ground ie what you are standing on and the shoes you are wearing whether you will remain safe by 'testing' for hotness on a circuit by touching it. @120V, 1.2 mA is enough to tell you that the line is live. 15mA is the let-go threshold, and 100mA can kill within a second. 200mA will pretty much kill instantly. Even at 120V on non-conductive ground, if you ever accidentally touched the grounded box while touching the live wire, you will likely be dead before the breaker trips. Steve
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Current thread:
- RE: Why choose 120 volts?, (continued)
- RE: Why choose 120 volts? Alex Rubenstein (May 26)
- RE: Why choose 120 volts? telmnstr (May 26)
- RE: Why choose 120 volts? Kurt Anderson (May 26)
- Re: Why choose 120 volts? Barney Wolff (May 26)
- Re: Why choose 120 volts? Andy Ringsmuth (May 26)
- Re: Why choose 120 volts? Ray Sanders (May 26)
- Re: Why choose 120 volts? Owen DeLong (May 26)
- Re: Why choose 120 volts? Ray Sanders (May 26)
- Re: Why choose 120 volts? Alex H. Ryu (May 26)
- Re: Why choose 120 volts? Barney Wolff (May 26)
- Re: Why choose 120 volts? Steve Bertrand (May 26)
- RE: Why choose 120 volts? Dave Larter (May 26)
- Re: Why choose 120 volts? Joe Greco (May 26)
- Re: Why choose 120 volts? Jared Mauch (May 26)
- RE: Why choose 120 volts? Dave Larter (May 26)
- Re: Why choose 120 volts? Alex H. Ryu (May 26)
- Re: Why choose 120 volts? Owen DeLong (May 26)
- Re: Why choose 120 volts? Brian Raaen (May 27)
- Re: Why choose 120 volts? Dorn Hetzel (May 27)
- Re: Why choose 120 volts? Peter Dambier (May 27)