Solid-state instantaneous trip device for a current limiting cir

Details Solid-state instantaneous trip device for a current limiting cir Solid-state instantaneous trip device for a current limiting cir

1987-04-13

1988-03-22

Pellinen, A. D.

Electricity: electrical systems and devices

Safety and protection of systems and devices

With specific current responsive fault sensor

361 97, H02H 3093

Patent

active

047333219

ABSTRACT:
An instantaneous solid-state trip device has two threshold values providing an upper and a lower tripping threshold. A current increase rate detector determines, when a short-circuit occurs, the prospective peak current value and, if the peak value corresponding to the electrodynamic withstand of the circuit breaker is liable to be exceeded, causes a change of threshold to bring about tripping, as soon as the lower threshold is exceeded. This high-speed tripping favours short-circuit current limiting. When a short-circuit of a lesser importance occurs, the current variation is lower and the instantaneous trip release only trips when the upper threshold is exceeded. In most cases, this upper threshold is not reached and tripping selectivity can be easily achieved in the usual way. A break in the circuit connecting the sensor to the trip unit also causes the circuit breaker to trip.

REFERENCES:
patent: 3654516 (1972-04-01), Tracursi
patent: 4012669 (1977-03-01), Gelfand et al.
patent: 4266259 (1981-05-01), Howell
patent: 4297741 (1981-10-01), Howell
patent: 4347541 (1982-08-01), Chen et al.
patent: 4442472 (1984-04-01), Pang et al.
patent: 4550360 (1985-10-01), Dougherty
patent: 4605982 (1986-08-01), Harner et al.
patent: 4642724 (1987-02-01), Ruta

Affiliated with

Also associated with

Rating

Solid-state instantaneous trip device for a current limiting cir does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Solid-state instantaneous trip device for a current limiting cir, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solid-state instantaneous trip device for a current limiting cir will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-445672