Ground integrity monitor for electrical apparatus

Details Ground integrity monitor for electrical apparatus Ground integrity monitor for electrical apparatus

1974-11-25

1976-12-07

Skudy, R.

Communications: electrical

Land vehicle alarms or indicators

Internal alarm or indicator responsive to a condition of the...

317 18A, 317 18C, 317 10, 340256, 324 51, H02H 300

Patent

active

039964965

ABSTRACT:
The ground and neutral terminals of a three-wire grounded AC power source for electrical apparatus, such as the control system of a motor operated hospital bed, are both normally connected to earth ground. The integrity or continuity of the ground connection is constantly monitored by applying, between the neutral and ground terminals, sharp narrow pulses periodically recurring at a relatively low pulse repetition frequency. When the resistance in the neutral/ground circuit is less than a predetermined threshold level, the pulsing causes an LED photo coupler to flash and this in turn produces a control signal for maintaining the electrical apparatus coupled to the AC power source. When the resistance between the neutral and ground terminals exceeds the threshold level, the AC power supplied to the apparatus is interrupted.

REFERENCES:
patent: 2999189 (1961-09-01), Gerrard
patent: 3176219 (1965-03-01), Behr
patent: 3402326 (1968-09-01), Guasco et al.
patent: 3496416 (1970-02-01), Agnew
patent: 3641547 (1972-02-01), Reiss et al.
patent: 3697808 (1972-10-01), Lee
patent: 3708721 (1973-01-01), Marcade et al.
patent: 3766434 (1973-10-01), Sherman
patent: 3810003 (1974-05-01), Portoulas
patent: 3840782 (1974-10-01), Monaghan

Affiliated with

Also associated with

Rating

Ground integrity monitor for electrical apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Ground integrity monitor for electrical apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ground integrity monitor for electrical apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-381397