Re: How does a probe screwdriver work?
Roy
Does it conduct through your body and to the ground?
While some so use the bodies resistence, No., They sense the magnetic
flux from the wire and light up.
bud--
> Does it conduct through your body and to the ground?
You might get an intelligent answer if you describe what you are talking
about.
--
bud--
Roy
From: remove....@isp.com (bud--)
-------------------
what the fuck does that mean - are you trying to snuff my response?
You're only stated that you don't know what a screwdriver type probe
tester is...
never seen one either eh Bud?
There's an old saying: "to a good understander, a few words are enough"
Roy Q.T.
[have tools, will travel]
Tomi Holger Engdahl
> Does it conduct through your body and to the ground?
SCREWDRIVER / VOLTAGE TESTER like this
http://www.allelectronics.com/make-a-store/item/SST-4/SCREWDRIVER-/-VOLTAGE-TESTER/1.html
http://www.maplin.co.uk/Module.aspx?ModuleNo=10294&doy=22m11&C=SO&U=strat15
work using following principle:
There is a high resistance resistor (limits current
through the device to safe sub-milliamprere level maximum)
and a neon bulb (lights at very low current).
The circuit is the same as used on neon lamp indicator
lights found on switches etc.. only difference being
that the current limiting resistor has higher resistance
(lower current) and safer design (will not arc over or fail on
any normal use or overvoltages).
When the tip is connected to live wire (or is near it so that there is
enough current through capacitance) there is a small current
that flows to your body to ground and makes the neon bulb to
put out some light. If you are touching ground with
other hand, the maximum current flows through your body
(limited to safe value with the current limiting resistor).
If you are not toucvhing ground the current flows to ground
through the capacitance between your body and ground
(still enough current
This kind voltage tester can fail in case you are very well insulated
away from ground sources. In that case there is not enough
"leakage" through you that the would make the neon bulb to flow.
Information on neon bulbs:
http://en.wikipedia.org/wiki/Neon_lamp
http://www.alibaba.com/product-gs/203745149/neon_bulb_with_resistor.html
--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/
Tomi Holger Engdahl
Practically all probe screwdrivers to test if there
is power on wire sense the voltage on the wire.
The simplest ones have just neon bulb + resistor
inside and there is some current flowing through your
body when you test. There are some more advanced
models that have some electronics
(usually high resistance resistor + FET + battery + LED)
that can work with much lower currents
(the capacitance through plastic of the handle
to your hand wil pass enough current to make sensor work).
Almost all sensors on the market I know are this type of
voltage sensors.
There are some magnetic sensors on tha market, but those
magnetig sensors are typically designed to sense
stronger magnetic fields on solenoids, relay coils,
contactor coils etc..
This kind of magnetic sensors are not normally
sensitive enough to sense magnetic field on wire
that carries just low currents...
Roy
Date: Fri, Sep 26, 2008, 5:11am (EDT+4) From: je...@hotmail.com (sert)
Does it conduct through your body and to the ground?
While some so use the bodies resistence, No., They sense the magnetic
\
Practically all probe screwdrivers to test if there is power on wire
sense the voltage on the wire. The simplest ones have just neon bulb +
resistor inside and there is some current flowing through your body when
you test. There are some more advanced models that have some electronics
(usually high resistance resistor + FET + battery + LED) that can work
with much lower currents
(the capacitance through plastic of the handle to your hand wil pass
enough current to make sensor work). Almost all sensors on the market I
know are this type of voltage sensors.
There are some magnetic sensors on tha market, but those magnetig
sensors are typically designed to sense stronger magnetic fields on
solenoids, relay coils, contactor coils etc..
This kind of magnetic sensors are not normally sensitive enough to sense
magnetic field on wire that carries just low currents...
--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/
Tomi:) that was very thorough.
-Thanks for that - I've seen that type of tester in shows - it looks
like a regular screwdriver but it lights up and actually pretty bright,
it would effectively light up your panel work - I have a smaller version
LED 1.5- 250 AC/DC Continuity tester that requires touching a clip on
the handle.I was just trying to be proactive;)
Now: When you get a chance look up Greenlee mo. no. GT-11 non-physical
contact Voltage Detector 50-1000 AC Cat IV., it's what I currently use,
4 simplicity.
Roy
but they sell those at the dollar stores here., I don't like them, nor
do I recommend them.
I use Sperry Instruments button battery operated model number HST 401
{touch required} great for testing bulbs & swtitches and the Greenlee
gadget of course.
Now: The brand name of regular or lineman sized one I saw at the show
eludes me - I'm just not that big with too much simplicity & light up my
work separately };-) but, If I find it I'll post it.
bud--
> Date: Mon, Sep 29, 2008, 12:41pm
> From: remove....@isp.com (bud--)
> sert wrote:
> Does it conduct through your body and to the ground?
>
> You might get an intelligent answer if you describe what you are talking
> about.
> --bud--
> -------------------
> what the fuck does that mean - are you trying to snuff my response?
It was your usual idiotic response. As Tomi points out there are a few
probes that operate on your "magnetic flux". It is very unlikely that is
what the OP has.
>
> You're only stated that you don't know what a screwdriver type probe
> tester is...
> never seen one either eh Bud?
Poor Roy. If you study real hard you could probably be the village idiot.
I have seen many kinds. Most operate with a neon light and capacitance
to 'ground' (as explained by Tomi). That is probably what the OP has.
With a better description from the OP one could be sure.
--
bud--
Roy
some years ago [those brave men] };-)
Roy
Date: Mon, Sep 29, 2008, 12:41pm
From: remove....@isp.com (bud--)
sert wrote:
Does it conduct through your body and to the ground?
You might get an intelligent answer if you describe what you are talking
about.
--bud--
-------------------
what the fuck does that mean - are you trying to snuff my response?
It was y/ our usual idiotic response. As
Tomi points out there are a few probes that operate on your "magnetic
flux". It is very unlikely that is what the OP has.
\
You're only stated that you don't know what a screwdriver type probe
tester is...
never seen one either eh Bud?
/
Poor Roy. If you study real hard you could probably be the village
idiot. [NO WAY]
I have seen many kinds. Most operate with a neon light and capacitance
to 'ground' (as explained by Tomi). That is probably what the OP has.
With a better description from the OP one could be sure.
-- bud--
-----------
I know., those in the posted pictures are crap - that's why I pointed
out the other types [The ones i use Rock] AYS; we'd be sure if the OP
did post a better descrip of the one he is talking about.
Who Me., Study?};-)