ATSman
ATSman
- Location
- San Francisco Bay Area
- Occupation
- Electrical Engineer/ Electrical Testing & Controls
Interesting article about net currents: currents that do not return back to the source on a neutral conductor but rather on building steel or water pipe. Our Master describes this with water pipes first hand at the end of the article:
http://www.mikeholt.com/technical.p...ed/EMIKarl&type=u&title=Power Quality Article
We ran into a similar situation at an office building where the employees were complaining about screen jitter on their work station monitors. The high Gauss readings (around 80mG) in the work area confirmed the cause of jitter and clamp-on readings of the ground wires terminated on the main switchboard (1600A) ground bus showed extremely high ground current readings. The utility transformer was located outside across the parking lot of this underground service. Turns out the neutral bus connection bolts were found finger tight in the transition section next to the transformer. Instead of the neutral current returning on the neutral bus, it was flowing through the building grounding system, building steel, earth and back to where the XO of the transformer was grounded. The building became an antenna for the EMF radiation. The neutral bolts were torqued: problem solved. The building operated like this for 4 years.
http://www.mikeholt.com/technical.p...ed/EMIKarl&type=u&title=Power Quality Article
We ran into a similar situation at an office building where the employees were complaining about screen jitter on their work station monitors. The high Gauss readings (around 80mG) in the work area confirmed the cause of jitter and clamp-on readings of the ground wires terminated on the main switchboard (1600A) ground bus showed extremely high ground current readings. The utility transformer was located outside across the parking lot of this underground service. Turns out the neutral bus connection bolts were found finger tight in the transition section next to the transformer. Instead of the neutral current returning on the neutral bus, it was flowing through the building grounding system, building steel, earth and back to where the XO of the transformer was grounded. The building became an antenna for the EMF radiation. The neutral bolts were torqued: problem solved. The building operated like this for 4 years.