Neutral-to-ground fault sensing circuit

Details Neutral-to-ground fault sensing circuit Neutral-to-ground fault sensing circuit

1993-09-24

1995-07-11

Hoff, Marc S.

Electricity: electrical systems and devices

Safety and protection of systems and devices

High voltage dissipation

361 56, 361 91, 361127, H02H 900

Patent

active

054326672

ABSTRACT:
A transient voltage surge suppressor (10) is used in a single or poly-phase power distribution network (P). The surge suppressor connects in parallel between each phase (A, B, C) and neutral (N), each phase and electrical ground (G), and between neutral and ground. An improvement comprises an electrical circuit (30) for monitoring the loss of surge protection due to the occurrence of a current surge or voltage transient in a neutral-to-ground path (32). An MOV-type semiconductor (VR1) is connected in the ground-to-neutral path. The semiconductor is normally non-conducting, but switches into conduction when its voltage threshold is exceeded by a surge current or voltage transient. An excessive surge or transient causes the semiconductor to fail. Respective fuses (F1A, F2B) are connected in series with the semiconductor. These fuses clear (blow) upon a semiconductor failure to create an open circuit neutral-to-ground path. An indicator lamp (20) provides an indication of loss of surge protection due to an excessive surge or transient. A semiconductor switch (42) controls lamp operation. The switch normally maintains the lamp in an ON state, but the switch is responsive to the fuses clearing to switch the lamp OFF. This is indicative of a loss of surge protection on the neutral-to-ground mode. An isolation element (44) is connected in the neutral-to-ground path and responds to clearing of the fuses to switch the semiconductor switch from ON to OFF.

REFERENCES:
patent: 4587588 (1986-05-01), Goldstein

Affiliated with

Also associated with

Rating

Neutral-to-ground fault sensing circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Neutral-to-ground fault sensing circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Neutral-to-ground fault sensing circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-507860