Recent content by ghostbuster7

Similar--- 2 mva. tx. core overheated and varnish/paint bled onto all the core laminations Problem: transformer exposed to incoming single phase fault situation for 91 minutes before H.V. breaker...

I.E.E.E. has hundreds of tutorials and papers on this subject over the last 50 years.Also keywords such as spacer dampers may help.

You may want to watch this recent grounding video that displays the different readings obtained using different instumentation. http://forums.mikeholt.com/showthread.php?t=159914

If there are VFD's or solid state rectifier's or U.P.S. systems in the area on this feed they will generate lots of voltage spikes.

I have reposted this in as suggested the corrosion group. Answers etc. The DC current is stray current from a city transportation system.They freely admit they are generating stray current and it is up to any new building designs to "accomodate" this stray current situation. Rebar inside this...

DCNew site to be designed. Measured 10 to 20 amps dc ground current at site.(Source of DC current will never go away and is generated by some other group). What is the best way to protect the rebar in the concrete from electrolysis? Epoxy coatings? Galvanizing? Sacrificial anodes? Thanks

New site to be designed. Measured 10 to 20 amps dc ground current at site.(Source of DC current will never go away and is generated by some other group). What is the best way to protect the rebar in the concrete from electrolysis? Epoxy coatings? Galvanizing? Sacrificial anodes? Thanks

Note: the ferrous loop will still carry current even if the loop formed does not encircle this conductor

Farmers have been placing large steel coils of fencing on the ground under the powerlines for years and dragging them into the barns at night to keep their livestock warm.

Also be aware placing the larger cap value on one side will lower the natural electrical system harmonic resonant point and could now line up with a harmonic generated by your loads.

Check with the geny rental groups.They are always supplying cam lock fittings with their stranded cable.

Our group also had image distortion problems with the High Frequency cotterizer that was used in the nearby operating rooms. As a test we got a slab of meat and a cotterizer and observed the 1 to 1 correspodence on the image distortions, as this test set-up was moved up and down the...

Yes,we have used this technique many times to detect failing SCR control circuitry within large mfg. plants.The last one I recall was failing scr circuitry for a 800 amp electric furnace used for baking black paint onto metal parts.Even current harmonics appeared at the main switchboard...

Maybe this will give you a different perspective: I just finished correcting a problem with 750 MCM. 1 single conductor per phase laid out in a flat configuration(not triangular). The ground cable was located beside the outer phase only for approx.200' run. Phase currents were 400 amps and...

You do not understand.There is no real answer until the exact specifics are all known. I can make this string break into corona at 200 kv. with the insulator string located close to the ground or at 400 kv. with the insulator string at 40-50 feet above ground. It all depends on the electrical...