190 vac from hot leg to switch leg

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cowboy1966 said:
Check for broken neutrals, and recheck all your grounding and bonding jumpers. You are getting what is called an objectionable current[/QUOTE
The thing that gets me is the odd readings at the panel. Come Monday I will shut all circuits off in the 277 panel and take some more readings and let ya'll know.
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Ohms law said:
I have 190 vac from constant hot to switch leg when my meter is set to high impedance setting. I have 0 vac when set to low impedence setting. This is a 277vac lighting circuit. There are many florescent and LED fixtures as well. I used a Klein MM2000 DMM. Any advice would be appreciated.
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I would agree with most, it is a phantom voltage when you read 190 volts on the high impedance scale
or input.

That is one of the new features of some of the new solid state testers they are competing with
the old selenoid testers by adding this low impedance input or scale.

Please watch the video

http://www.homedepot.com/p/Klein-Tools-True-RMS-Digital-Multimeter-MM2000/202521275
 
ronaldrc said:
I would agree with most, it is a phantom voltage when you read 190 volts on the high impedance scale
or input.


That is one of the new features of some of the new solid state testers they are competing with
the old selenoid testers by adding this low impedance input or scale.

Please watch the video

http://www.homedepot.com/p/Klein-Tools-True-RMS-Digital-Multimeter-MM2000/202521275
Click to expand...

Have you read post #12? I reposted my voltage readings with high impedence and low impedence setting.
Thank you for the video, im not sure why you wanted me to watch it though. I know how to use the two different settings.
The fact I had 60vac on low impedence setting is why I am questioning my predicament. I want make sure there are no safety issues that may come up, for instance any grounding/bonding issues.
 
Ohms law said:
Have you read post #12? I reposted my voltage readings with high impedence and low impedence setting.
Thank you for the video, im not sure why you wanted me to watch it though. I know how to use the two different settings.
The fact I had 60vac on low impedence setting is why I am questioning my predicament. I want make sure there are no safety issues that may come up, for instance any grounding/bonding issues.
Click to expand...


Very,Very Sorry I caused you to waste your Time
 
141130-1632 EST

Ohms law:

I think the 60 V reading is what everyone is concerned about, and it is always the same value.

My suggestion:
1. Disconnect all hot wires in a bundle, cable, or conduit. In other words in close proximity to each other.
2. Leave the EGC, and neutral (if there is one) connected.
3. Using high impedance meter measure voltage between EGC and neutral. This should be virtually zero. If wires are in conduit the reading might be a few millivolts. If not, then why? Voltage might be somewhat higher without the shielding of the conduit. If EGC and netural are not bonded at the panel, then expect a few volts.
4. If there is a neutral that travels with the hot wires, then use it as a reference. Otherwise use the EGC as the reference.
5. Relative to your reference measure the voltage (high impedance) of each hot wire. Should be near zero.
6. If the above are OK, then energize one hot line, and proceed with all of the above measurements. You should see the capacitively coupled voltage in high impedance, and near zero volts in the low impedance mode.
&. Describe your meter for both high impedance and low imp[edance.

.
 
The instructions for you meter put the low-impedance setting at >3k ohm minimum. If you could guarantee a 3000 ohm meter impedance, I would agree that there is very likely a high-resistance circuit on those conductors in order to maintain 43mA of constant current flow.

That said, my understanding is that many of these electronic low-impedance settings have variable resistance that are voltage dependent, so when measuring anything less than the maximum input voltage, you may have a much impedance than that.

I still think this is capacitive coupling. I would write to Klein and ask what the Z/V ratio was for the meter impedance.
 
Ohms law said:
I am assuming that because of the sarcasm you must have taken my response in a negative way, I apologize. That was not my intention.
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And I apologize in return. I did not mean to belittle you with that video. I'm sure we all
feel like that at times I know I do.

Ronald :)
 
If you question the 60 volts on the low impedance meter - put a load across the two points being checked incandescent lamp of most any wattage should work great. If there is real power behind that 60 volts it will not change much with the load connected to it. If it is capacitive coupled voltage it will likely go completely away.

If it has some real power behind it the next challenge since you are measuring something is supposed to be "off", is to find out just what the source really is.
 
I suspect it's a limitation in the LowZ circuit of that DMM. I'm not seeing any warning in the instructions to limit the amount of time you have it connected, so I don't think it's actually using a resistor to achieve the low impedance reading. Any of the DMMs with LowZ that I've used have been very specific about not leaving them connected to a live circuit for more than a few minutes without a cool-down period afterwards.
 
kwired said:
If you question the 60 volts on the low impedance meter - put a load across the two points being checked incandescent lamp of most any wattage should work great. If there is real power behind that 60 volts it will not change much with the load connected to it. If it is capacitive coupled voltage it will likely go completely away.

If it has some real power behind it the next challenge since you are measuring something is supposed to be "off", is to find out just what the source really is.
Click to expand...
I put a resistive load (72watt halogen 120vac) on it today and then measured with lowZ setting. The result was 0vac. I also measured from a the switch leg (off positon) to the neutral with my meter to check capacitance. The result was 4.96nF. That's all I had time for today.
 
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