753MTE
Member
- Location
- Highland, Indiana, USA
Has anyone come across a non-contact tester for DC up to 250vdc?
Non-Contact DC tester
- Thread starter 753MTE
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- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
You can easily have a non-contact current sensor for DC, but there is no practical way to sense actual voltage that way that will not be vulnerable to zero drift and false readings. (I suppose you could dangle a static-charged ball from a string, but it would not be practical.)
SG-1
Senior Member
- Location
- Ware Shoals, South Carolina
Do you mean something like this ?
They have another one that is more sensitive, down to one gauss.
http://www.mitchellinstrument.com/e...detection-pens/mag-probe-magnetic-tester.html
They have another one that is more sensitive, down to one gauss.
http://www.mitchellinstrument.com/e...detection-pens/mag-probe-magnetic-tester.html
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
The gauss is a measure of magnetic field. That is just fine for detecting current, regardless of the voltage or frequency, but will do nothing to detect an energized wire which is not carrying current.
SG-1
Senior Member
- Location
- Ware Shoals, South Carolina
The Mag-Probe primary purpose is to determine if relay coils are energized.
This is the only non-contact DC tester that I know of.
gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
130501-2256 EDT
With a 9 v battery, an MPF103 (FET), some resistors and a diode for reverse protection on the gate I can sense fields from a 20 VDC or less source. Also great for static charge sensing on a rubbed glass or plastic rod. For high fields an LED is a useful indicator.
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With a 9 v battery, an MPF103 (FET), some resistors and a diode for reverse protection on the gate I can sense fields from a 20 VDC or less source. Also great for static charge sensing on a rubbed glass or plastic rod. For high fields an LED is a useful indicator.
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broadgage
Senior Member
- Location
- London, England
I do not believe that a useful non contact DC voltage detector can be made.
Although ways exist of detecting a DC electrostatic field this would not reliably determine if a conductor was energised or not.
Electric fields from static/friction would be far greater and give rise to so many false readings as to render such a device useless.
Although ways exist of detecting a DC electrostatic field this would not reliably determine if a conductor was energised or not.
Electric fields from static/friction would be far greater and give rise to so many false readings as to render such a device useless.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Would you consider a clamp-on ammeter to be a non-contact tester? They are available for DC too.
SG-1
Senior Member
- Location
- Ware Shoals, South Carolina
Good point, I have a Fluke 90i610s & 337. Wonderful use of the hall effect.
I would really like to have the non-contact voltmeter that uses the laser beam.
I would really like to have the non-contact voltmeter that uses the laser beam.
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I regularly use a Hall-effect clamp on for current but I think the OP is asking about voltage.
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