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Wireless Mains Voltage Indication System/Alarm

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May 1, 2010
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Anyone know where can i get the Wireless Mains Voltage Indication System/Alarm schematic? It is very usefull for the field workers who worked in Electricity Field........

I want your valuable suggetion for the above......sorry for my poor English

and thanks in advance......

Is this what you are looking for? **broken link removed**

By wire less if you mean contactless then there are devices based on Rogowski coil, Kerr effect, Pockels effect etc. However the later two suit for higher voltages and require additional sophisticated techniques.
Else the problem boils down to remote monitoring.

I mean what I need....I need to detect power in the transmission line when the line is active...Is it possible? I get more Idea from internet. I try to build one..But nothing happen.

I need just like Metal Detector...and i want to detect Power in the line.

i think you understand my question...

Sorry for my poor English........

Thanks for your Replay...ark5230

Would a commercial current clamp meter do the job?

The kind that has wide jaws that you clamp around a wire and you read how much current it's carrying.

Current clamp - Wikipedia, the free encyclopedia

The wire must be easy to reach. And it must be a single wire.
What if there is no load connected and there is no current flowing? The clamp meter will read 0 amps but the cable still has potential to kill someone.

What if there is no load connected and there is no current flowing? The clamp meter will read 0 amps but the cable still has potential to kill someone.

Then he can't use a current clamp meter for that.

There are commercially made instruments that will detect a live mains wire several inches away, even when it's not carrying current. Don't know how I would make a detector that does that.

Voltage detector - Wikipedia, the free encyclopedia

"AC detectors"

"A very different kind, also called an AC detector, detects the electrical field present around any wire which is connected to an AC source of 50 or 60 hertz. It never touches the wire, and typically has both an LED that glows and an audible noise. These get brighter and louder as the field increases closer to the wire. AC detectors can be used even if no current is flowing through the wire in question."

---------- Post added at 14:44 ---------- Previous post was at 14:34 ----------

Now I get it. The OP wants to make such a device himself.

I would start by experimenting with an FET. These can detect static charge from several feet away.

If a mains wire is nearby, an FET will respond with square waves. Because it is greatly amplifying nearby sine waves transmitted from mains wiring.

It needs an antenna connected to the input terminal.

Many IC devices have sensitive enough inputs to do the same thing. (Although they're not as sensitive as an FET, unless they have FET input.) That's the reason for advice to connect unused inputs to supply + or ground.

Just by touching one finger to the oscilloscope lead, I see sine waves which are several mV amplitude.
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