How to calculate the groundness

  • Thread starter Thread starter pixel01
  • Start date Start date
Click For Summary

Discussion Overview

The discussion revolves around the concept of "groundness" as specified for the installation of an instrument, particularly focusing on the unit of measurement (<0.5V/ms) and how to measure it. Participants explore the implications of this specification in the context of electrical installations.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • One participant expresses confusion about the term "groundness" and its measurement unit, seeking clarification.
  • Another participant suggests that the specification might relate to GFCI (Ground Fault Circuit Interrupter) standards due to the time component involved.
  • A later reply indicates that the specification might actually refer to <0.5 volt rms, questioning the original interpretation of the unit.
  • Participants discuss the method for measuring ground to neutral voltage, with one suggesting the use of a voltmeter and another emphasizing the importance of safety and possibly involving an electrician.
  • There is a suggestion that the measurement should be taken at the instrument's location rather than at the distribution panel.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct interpretation of "groundness" or the appropriate measurement method, indicating multiple competing views and ongoing uncertainty.

Contextual Notes

There are limitations regarding the clarity of the specification and the assumptions about measurement locations, which remain unresolved in the discussion.

pixel01
Messages
688
Reaction score
1
Dear all,

I am going to install an instrument. As usual, it needs ground wire and I have it installed.
However in the specs they require that the groundness is <0.5V/ms. I really do not understand that unit and how do they measure the goundness.

Thanks for any ideas.

Regards
 
Engineering news on Phys.org
pixel01 said:
Dear all,

I am going to install an instrument. As usual, it needs ground wire and I have it installed.
However in the specs they require that the groundness is <0.5V/ms. I really do not understand that unit and how do they measure the goundness.

Thanks for any ideas.

Regards

Yeah, that's a new word for me as well. Maybe related to some GFCI spec, since there's a time component to the spec. Can you post a link to the product and datasheet?
 
berkeman said:
Yeah, that's a new word for me as well. Maybe related to some GFCI spec, since there's a time component to the spec. Can you post a link to the product and datasheet?

Sorry for the late reply. Our lab is going to install an ICP instrument and the customer engineer asks us to prepare some conditions for the installation. About the electricity he wrote: "All the powerlines must have groundness (Ground to Neutral <0.5V ms)"
 
Sounds like it's just a language translation thing. Thanks for the clarification, pixel.
 
Don't you mean <0.5 volt rms? Root Mean Square voltage value of AC on the neutral?
 
dlgoff said:
Don't you mean <0.5 volt rms? Root Mean Square voltage value of AC on the neutral?

Oh, thank you. That's correct, the fax is dim and the 'r' is almost gone.
Anyway, how can I check the 'gound to neutral' smaller than 0.5V ?
 
pixel01 said:
Oh, thank you. That's correct, the fax is dim and the 'r' is almost gone.
Anyway, how can I check the 'gound to neutral' smaller than 0.5V ?
Just set your volt meter to measure ac rms volts and connect it between ground and neutral wire at the distribution panel.
You might want to get electrician to do the measurement if you are uncomfortable with the getting into the panels however. Safety first.

Edit: On second thought, maybe the measurement should be made at the instrument location. Maybe someone else here knows where the appropriate place to make it.
 
Last edited:

Similar threads

Question about bonding ground and neutral
  • · Replies 7 ·
Replies
7
Views
3K
Resistance, capacitance, inductance of a real wire
  • · Replies 2 ·
Replies
2
Views
2K
Overvoltage Protection
  • · Replies 5 ·
Replies
5
Views
2K
Earth ground meter Vs Multimeter
  • · Replies 1 ·
Replies
1
Views
2K
Considering Earth ground vs floating ground in off grid solar
  • · Replies 13 ·
Replies
13
Views
7K
Help with proper grounding with oscilloscope tracings
  • · Replies 21 ·
Replies
21
Views
3K
"Ground" and "Center Tapped" Power Transformer Secondary in guitar amp
  • · Replies 6 ·
Replies
6
Views
4K
Generator tripping on ground fault during load test
  • · Replies 38 ·
2
Replies
38
Views
8K
Residual voltage on a ground wire
  • · Replies 18 ·
Replies
18
Views
5K
Recessed Lighting: Wiring Puzzle--How is this Possible
  • · Replies 18 ·
Replies
18
Views
2K