Phantom Voltage

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brian john said:
Details please?
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Your extension cord test in Post #5 describes an open ground wire, doesn't it? The Ideal 61-501 shows an open ground. Using a high impedance meter this will show up as stray voltage.

In your field problem, it "appears" that all wires are properly connected. Three wire conductor is used because half of the duplex is switched, your picking up stray voltage from the extra wire.

A Fluke VoltAlert 1AC-A-II will also detect that stray voltage on a open ground too. It wil react the same way on a open neutral also. Stray voltage isn't always a bad thing in some ways.
 
Contacted a very helpful applications engineer at Ideal today. He said they are aware of this issue, but have not put out any application notices on this issue. He offered to contact the inspector and explain the situation if necessary.
 
new test 10-3 NM

10-3 NM Megger Test
CONDUCTOR CONDUCTOR READINGS IN GIGAOHMS
Black Bare 11.0 *1
Red Bare 11.0 *1
White Bare 11.0 *1
Black Red 11.0 *1
Black White 11.0 *1
Red White 11.0 *1
*1 - 11.0 Gigaohms is full scale reading of the calibrated Fluke Model 1507 Insulation Tester, megohmmeter utilized for this test


Voltage Test Black, Red Energized, White connected to Grounded Conductor termination bar and Bare connected to grounding termination bar
CONDUCTOR CONDUCTOR READINGS IN GIGAOHMS
Black Bare 121.24 VAC
Red Bare 121.44 VAC
White Bare 75.8 millivolts AC
Black Red 211.1 VAC
Black White 121.24 VAC
Red White 121.48 VAC


Voltage Test Black Energized, Red De-energized White connected to Grounded Conductor termination bar and Bare connected to grounding termination bar

CONDUCTOR CONDUCTOR READINGS IN GIGAOHMS
Black Bare 121.15 VAC
Red Bare 43.49 VAC
White Bare 75.30 millivolts AC
Black Red 211.1 VAC
Black White 121.15 VAC
Red White 43.63 VAC

Short Rec to Neutral oe EGC and voltage drops to less that 48.0 millivolts AC
 
new test utilizing 10-3 NM

Neutral/grounded conductor terminated in panel on neutral termination bar, bare. EGC connecteed to EGC termination bar Balck connected to CB, Red connected to CB.'

When the Ideal 61-501 is connected with proper polarity it lights CORRECT. When connected with the proper polarity to the red conductor and then the red conductor is disconnected from the CB the center light is illuminated dimly. Ground the red conductor (with power off) the Ideal illuminated dimly light goes out.



IDEAL.jpg
 
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Sorry for the double post I thought I had deleted the first of the last two post...

Oh and I just purchased the Fluke SV225 Stray Voltage Eliminator.
 
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Don I proofread this 5 times that should be 68.03 VAC...AGGGGGGGGGGGGGGG.

I AM glad someone caught that of 3 people in my office no one say it including me....Thank goodness this had not been sent to the AHJ .
 
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090210-1702 EST

brian:

What is the length of the cable? Is there any load connected to the end of the cable? Are RED and BLACK connected to opposite ends of a center tapped secondary? What meter did you use?

It is strange that BLACK to RED read 211 V and not 2*121 = 242 V. Or is this 3 phase Y.

Then in your last test it is strange that BLACK to RED still read 211 V with red supposedly floating, while RED to WHITE is 43 V. Something is inconsistent.

.
 
I see this thread is still floating. For those of you who DON'T know, Fluke's 114,116, 117, and the new 289 are dual impedance meters. No need for the solenoid testers or the adapters such as the SV225:wink:
 
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76nemo said:
I see this thread is still floating. For those of you who DON'T know, Fluke's 114,116, 117, and the new 289 are dual impedance meters. No need for the solenoid testers or the adapters such as the SV225:wink:
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I am actually looking for a new meter and was looking at the fluke's you mentioned. I was leaning toward the 289 but the 117 looks okay to. what are your opinions on these models. I was not impressed with the .09% on the dc voltage.
 
cschmid said:
I am actually looking for a new meter and was looking at the fluke's you mentioned. I was leaning toward the 289 but the 117 looks okay to. what are your opinions on these models. I was not impressed with the .09% on the dc voltage.
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The 289 looks nice, which I have not touched yet, hate the size and bulk of it though. I don't like the 117 for different reasons. I went with the 116. They're small and comfortable and they accept the TPAK tool hanger which is far better than sliced bread. The 116 is an everyday meter beyond what I need past the T5-1000, and it's the 87V past that:wink:
 
cschmid, the 289 and the 117 are apples and oranges as you know. You want a logger in your new meter? I don't have any opinions on the 289, but there have been a few negatives, backstand for one. I forget thee other one.

I NEVER liked the 189 either because of it's size/bulk. The 289 looks slightly larger overall. If I am going to carry anything that big, it'd be a scope or PQA, not an everyday DMM.

Check out the 116 or look more at the 289. I know Ken, (480sparky) received a 289 for Christmas and seems to really like it. Anyone else have the new 289 here and have more opinion on it??????


Chris, (electricalperson), has the 117 and seems to really like it, it's just all to each their own:wink:
 
the only info I have is what little I have read but I would hate to by it just to find the quirks are what I am working on. So all input is appreciated..So in the right of not high jacking this thread I will start a new one.
 
I should have posted this on Friday but it slipped my mind. The inspector read my report/letter and is now passing all the condo units he is called in to final.
 
Phamton Voltage

Phamton Voltage

There is a possibility that you are reading an actual voltage when you use a Fluke DDM or a newer model Simpson. Is you Simpson an older style 260? If it is, then you may indeed have a problem.

The input impedance of the Fluke DDM can range from about 8 to 10 megga-Ohms. On DC circuits this may be user selected to 25 megga-ohms by the user. What this means to a user is that the meter samples a very small amount of current to measure the circuit voltage. Thus induced or capacitively coupled circuits will cause a Fluke meter to read a voltage. As to it being a phamton voltage, well, it is real enough, but the internal impedance of the circuit very high, thus when you try to draw currents at a level above a few micro-amps, all the voltage is dropped on accross internal impedance.

As far as the Ideal 61-501, I am very surprised this would detect such a high impedance voltage source. I have teh Ideal 61-501 and have never noticed this concern.

I hope this helps.
 
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