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Proximity Detectors

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Cam83

Electrical
Jun 26, 2003
3
I am after a non-contact voltage detector(proximity detector) that has the following capabilities:
1)Ability to detect as low as 10V and high as 500V.
2)Self Test function.
3)No sensitivity adjustment.
Does anyone know of such a device?

Also, does anyone know if such devices will operate reliably whilst in close proximity to HV Power Lines ie. 11kV to 66kV?

 
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Could you not out a coil around the conductor you are measuring. There would then be a current induced in the coil proportional to the current going through the conductor. I dont think that the HV lines around it will have an effect either.
 
proximity devices typically employ a hall effect element. These devices sense the presence of a magnetic field. In practical application, currents (not voltage) can be measured by sensing there associative magnetic fields. Voltage calculations may then be performed. The elements are stable and not injured by overexposure to magnetic fields. Calibration is not required after initial setup. Self test would be a function of the resolving circuit, which would likely include verifying it's communicative ability to the outside world.
 
The posting was to detect voltage not current. Coils and hall effect sensors are not usually used to detect voltage.

CAM83, are you interest in detecting DC, or AC? if AC what frequency?
Why can't you connect to the 10 to 500 volts using a high resistance resistor?
More details on what you are trying to do would be helpful for the best solution.
 
You might be able to use an ESD monitor to detect DC electric fields, particularly at close range

TTFN
 
I dont know how you would detect voltage without physically intervening in the circuit. There is no field associated with voltage on its own. There must be current flow (magnetic field). I am not familiar, too much, with these personal detecting devices but can't imagine how they would detect a voltage (especially with no current flow). Anyone real familiar with these personal protective devices?
 
To detect HV 60Hz is easy -- use a FET input 60Hz amp-- with input protection. You could pick up sufficient electric field from considerable distance.



<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032
 
Buzzp,
you say there is no field associated with a voltage. Remember the electric field? Voltages give rise to electric fields. Currents give rise to magnetic fields.

In order to sense an electric field, an earth reference would be needed. Either that or the probe would only be able to sense a local gradient in the field.

Cam83
if the probe is detecting voltage, then the closer it gets to the source, the larger the reading will be. Also the shape of the source will affect the reading. Calibration would be meaningless. But then you say you want to detect 10V in the presence of 66kV power lines. Unless the voltage you are sensing is a different frequency (such as DC) to the high voltage power cables, the high voltage power cables will almost certainly "swamp" any readings of the small voltage.
 
Logbook, My bad. Thanks for pointing that out.
 
Indeed, sorry I didnt read the post properly.

I do agree with logbook. I cannot see that any sensing of such a small voltage will not be affected by the HV lines.

 
Isn't this what a Tic Tracer does? They have been around for years.

&quot;Venditori de oleum-vipera non vigere excordis populi&quot;


 
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