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I have a very basic electric live wire tester. A simple device that otherwise looks like a screwdriver with resistor and a neon inside it. Image source WiKi

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I connect one end to the live wire and when I touch the other end the neon glows if the tester in fact was connected to the live wire.

I have gone thru this post and it’s very informative. Still it’s hard for me to understand its working! Just a question comes to my mind, what if while I touch the other end of the tester, I am completely floating in air, even my shoes not touching any ground? Will the neon glow in that case? Can circuit complete thru ground then air then human body and the tester?

rajeev
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2 Answers2

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Yes. It is your body surface area and dielectric fluids of capacitance that acts the interface to dielectric of freespace air and not the ground conduction or your feet.

Tony Stewart EE75
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If you are hanging in air, then the capacitive coupling between your body and ground will be very weak to make the neon indicator glow. If you have noticed, there is a difference in brightness of the line tester if the floor is wet or dry. The indicator glows brighter if the floor is wet, and glows dimmer if the floor is dry or if you are wearing a rubber boot.

SRK
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