If you know the number of turns and approximate dimensions of the cut and secondary tails you can calculate the figure using the standard resistivity value of copper.
Sm2000 - I was recently involved with such measurements. The measurements use machine speed , current and voltage signal to derive the natural frequencies of torsional oscillations of the combined system (generator& turbines). That information can then be used or compared with the sub...
Rasevskii, my interest is not the relay but the CT. We changed a transformer from 3 x single phase gen trans bank. The new transformer came with it's own cts(coz the originals could not fit) . we've done mag currents on the cts on their own. Like i said in my first post - i ain't really sure...
It is proposed to carry out secondary injection with the relay still connected to the CTs (not using test terminals but injecting directly onto the loop). Has anyone done such a test before, i doubt it is meanful?
Oil temperature and winding temperature indication won't show you true hot spot temperature. oil temperature will always be less than any hot spot temperature because of it's mass and effect of the cooling system. Winding temperature is based on a combination of oil temperature and a derivative...
I recently had a contractor doing ratio tests on our transformers but they were using the reference capacitor method instead of the conventional voltage method. They basically used a capacitor of known size in series with one winding while applying high voltage (11KV) on the other winding (HV)...
