On of my receptacles which is the last one in the series showes to have
an open ground as detected by my plug in test set. When i test with
my non contact voltage pen and move it near the neutral on the
receptacle it beeps showing the presence of current. None of my other
receptacles do that.
The receptacle prior to this one test just fine. I removed the last
bad receptacle and verfiied that the ground wire is secured on. Also
the hot and neutral wires are inserted at the back of the receptacle
instead of being screwed on.
Before i go about replacing the receptacle is there anything else to
the device you are using is not as reliable as a meter.
next tools to buy:
digital multimeter. and a gfi tester [like an outlet polarity tester
with a test button].
basic wiring info at:
Note that these testers will indicate a bad ground but don't necessarily
indicate a good ground. If the ground is high resistance they will still
indicate the ground as being good. You have to draw significant current
to test for a good ground.
Also a digital meter may give less accurate results. Digital meters have
a very high resistance. With 2 wires run together, one hot and the other
not connected to anything, a digital meter may measure voltage on the
disconnected wire through capacitive coupling. A low resistance analog
meter is likely more accurate. Or a meter in parallel with a 100W lite bulb.
I think there is a lot of hip hopping around about
First, you should believe your plug in circuit
tester, but realize that if you have more than one
problem, the reading may be a bit quirky. OTOH,
I'm not sure I would believe the voltage pen.
The first step is to replace the receptacle with
screw type wire connectors because you should do
that anyway. Make sure that you wire it correctly
and don't reverse the polarity. Then plug in your
circuit tester and see what it reads. Chances are
it will be fixed.
If you really want to test the ground with a load,
and understand that almost no one does (they just
test for continuity), then test with a 100 watt
bulb. Unplug any type of small lamp (table or work
lamp), attach flexible leads tightly to the
neutral and the hot plug points. I would look for
a plug with holes in the plugs and use small bolts
to attach the wires. Do what you feel necessary
for safety, e.g., wrap the plug in tape. Touch one
lead to the hot slot of the receptacle and one to
the grounding hole. You probably shouldn't do such
a test except on a circuit with a regular breaker.
"open" means not connected. The ground to that receptacle is not
connected. You may measure 0 volts (with nothing connected), but it
will not act as a safety ground. This is not a grounded outlet.
Also, according to another poster, this could be a symptom of a
hot-neutral reversal. This should be fixed. Then check the ground
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