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skywalker

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> belt from between 80 and 150 ac can be unpleasant but is not as dangerous.

Depends entirely on circumstances. A person has been killed by 32V and another person survived 220kV. I wouldn't like to generalise, but it would be interesting to see how many Americans are killed by 110VAC. Electrocution depends on current much more than it does voltage. It also depends on skin resistance, humidity and especially frequency. Heart muscle response time is about 3mS, so get near the resonant frequency of that and I would a few volts would see you in trouble. It's a much more complicated subject than meets the eye. I've had phase to phase hand to hand and walked away without a flinch. I've also had single phase hand to foot/earth and jumped about and swore loudly.

> if so, the neon because it will indicate from below to 500 volts, is highly reliable at warning of a possible

> (i.e. higher) dangerous voltage potential?

Can I assume we are talking about a neon indicator which has just the spike probe, no other wires?. That's how they were when I last saw one. In that case, to answer your question, you'd have to ask "where does the return current go". The only way I can see it working is by cacpacitive coupling to you, ie the return current goes through you to earth. So at the instant of peak voltage on the AC cycle I lift the probe and very quickly touch it on earth. The capacitance must hold that peak voltage for a while, and we just earthed the bit that was charged to +400V, so what part of the probe or you gets to see the -400V spike?

I dunno, some people like them, but I wouldn't recommend anybody use a probe to measure 400+ volts when they form part of the current path.

bee

come on b, be serious, you can kill yourself by gulping down salted peanuts!

i bet their is a vulnerability that will kill at 32 volts, ill health or supercharging grannies pace maker to get at the will for instance.

but you gonna need 2 points of contact very close together near direct on an organ to achieve it, the prior access wound would likely kill first.

as for 415, i do have an socket & see make 'easy phase finder' EPF10 to identify phase's, bought it as seemed a 'good idea' at the tie, just so i can find if a baby alarm type mains intercom will work between buildings, interference checks on PSU for cameras etc. - but never used it as yet.

If you think education is difficult, try being stupid!!!!

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my 3 yellow trannie's and when on site i'v only ever been offered 110, never yet ever seen 25 or 55 options, and have nothing that works off it either., so never looked hard. i won't go anywhere near 415 - even with my gold laminated neon thank you.

.

I suspect I'm wasting my breath here, but you misunderstand the concept of a 110 site transformer with a centre tap to earth. If you were to make contact with one side of the output from a 110v CTE transformer and then make contact with earth, the maximum voltage between those two points is 55v (due to the centre tap) hence it is much safer to use on a building site where leads and extensions can be easily damaged and frayed. Of course, if you put yourself across both sides of the output, you'll get 110 volts.

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phone range

i am talking about the basic neon driver as bought anywhere, not the led version.

this device requires you stick the blade to the supposed conductor to test for potential, then touch the other end of the handle with a finger for it to glow.

your going into theory but seems without the components involved. the neon indicator itself has an extremely high ressitance value, it is the presence of 90 vac that causes the inert gas to strike glow, passing inline with that is a very high value resistor that is required to reduces the voltage at the neon and allows the neon to work upto 500 volts without damage, then there is a low value fuse inline also

even if the neon is damaged by an impact and presented a short via electrodes, the inline resistor is more than high enough to prevent more than a few micro amps flowing at stated maximum voltage.

not advisable in daylight because it is not a powerful light source, but inside a home or inside a cupboard not an issue for diy.

If you think education is difficult, try being stupid!!!!

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Arfwit, you have yet again show your complete ignorance on the subject.

Do yourself and everyone else a favour and stop lecturing on the subject.

You are dangerous . End of.

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Arfwit, you have yet again show your complete ignorance on the subject.

Do yourself and everyone else a favour and stop lecturing on the subject.

You are dangerous . End of.

perhaps instead of hiding behind generalisations especially while stating i'm dangerous yet again, do you care to point and prove what i don't get instead? - show everyone you superior knowledge.

as for being dangerous, your the man based on a one day course, that supports not double checking because its a wast of time - yee gods and you have the balls to dare to keep posting in here?

If you think education is difficult, try being stupid!!!!

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I suspect I'm wasting my breath here, but you misunderstand the concept of a 110 site transformer with a centre tap to earth. If you were to make contact with one side of the output from a 110v CTE transformer and then make contact with earth, the maximum voltage between those two points is 55v (due to the centre tap) hence it is much safer to use on a building site where leads and extensions can be easily damaged and frayed. Of course, if you put yourself across both sides of the output, you'll get 110 volts.

your not wasting your time,

i do fully understand the concept of 110. but it gets desperate when members having been reamed earlier throw this what is in general an uncommon voltage into a conversation, then toss in others even lower.

if common sense testing for 'live', conceived as a serious potential to kill, and the area where i'm talking about.

tbf it is a built in safety feature of 110 site supplies, if i grab the live in one hand and the neutral in the other NOT the earth i will still get a decent wallop for my stupidity, still not a good idea but less likely to be a fatal shock as long as i have decent health.

compare that to 240 in a house, grab both sides path through the heart 3 ma often kills, or causes heart attack even stroke, but not always due to ill health, length of exposure and lmb rcd tripping time.

Far safer today than old fuse wires, but still need to be treated with greatest respect, to do that you need to understand the frailties of meter leads, and to test the properly, thats not just by using a simple loop test.

If you think education is difficult, try being stupid!!!!

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perhaps instead of hiding behind generalisations especially while stating i'm dangerous yet again, do you care to point and prove what i don't get instead? - show everyone you superior knowledge.

as for being dangerous, your the man based on a one day course, that supports not double checking because its a wast of time - yee gods and you have the balls to dare to keep posting in here?

Yet again the imbicile shows his inability to read and comprehend even basic information.

Care to point out where i said i have only done a one way course?

Thought not.

As for qualifications and training, don't embarass yourself further.

Now back to the village, they're missing you

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Have to say as the number of older installations with RCDs increases, and some are now 15-20 years old, I am constantly

finding ones that do not trip when I'm doing my minor works certs.

Can't believe some people don't understand the basic concept of Centre Tapped 110V though.

When you ramp test them do they eventually trip or not at all.

Had a few 30's go at 33 :(

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