Field ground fault detector and field ground fault relay for det

Electricity: electrical systems and devices – Safety and protection of systems and devices – Ground fault protection

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

361 20, 361 23, H02H 300

Patent

active

056754655

ABSTRACT:
According to a field ground fault detector, a predetermined resistor is connected in series to a predetermined DC voltage. A DC voltage is applied between an N electrode side field circuit of a generator and a ground through the resistor. A voltage applied between terminals of the resistor is input to a low-pass filter. A voltage applied between the N electrode side field circuit and the ground is input to another low-pass filter. Output voltages of the low-pass filters are input to a level ratio determining circuit. The level ratio determining circuit outputs the determined result of the ground fault to the outside of the field ground fault detector corresponding to these voltages. Thus, even if the DC voltage varies or a higher harmonic voltage takes place in a generator of a thyristor exciting type, it does not affect the detecting sensitivity of the ground fault.

REFERENCES:
patent: 4187525 (1980-02-01), Nagura
patent: 4410925 (1983-10-01), Tucker et al.
patent: 4679111 (1987-07-01), Koch et al.
patent: 4864242 (1989-09-01), Hurley
Patent Abstracts of Japan, vol. 8, No. 229 (E-273), Oct. 20, 1984, JP59110395.
Patent Abstracts of Japan, vol. 5, No. 42 (P-053), Mar. 20, 1981, JP55164378.
Patent Abstracts of Japan, vol. 15, No. 486 (E-1143), Dec. 10, 1991, JP03212117.
Elektrotechnik, "Erkennt Effektivwerte, Leistungsschalter Mit RMS-Messystem," vol. 71, No. 4, Jun. 1989, p. 40.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Field ground fault detector and field ground fault relay for det does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Field ground fault detector and field ground fault relay for det, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Field ground fault detector and field ground fault relay for det will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2361944

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.