| Technology Research Corporation Patent applications |
| Patent application number | Title | Published |
|---|
| 20100039090 | Voltage compensation circuit - A voltage compensation circuit is disclosed for proving an elevated output AC voltage upon an under voltage input AC voltage condition. The voltage compensation circuit comprises an autotransformer having a first and a second autotransformer winding. A first position of a switch connects the first autotransformer winding to the input AC voltage for providing an elevated output AC voltage at the second autotransformer winding. The second position of the switch shorting the first autotransformer winding for providing a non-elevated output AC voltage. | 02-18-2010 |
| 20100020452 | Leakage current detection and interruption circuit powered by leakage current - A circuit is disclosed for disconnecting a power source upon the detection of a leakage current from one of a first and a second wire connected to the power source. A sensing conductor is located adjacent to one of the first and second wires for sensing a leakage current from one of the first and second wires. A disconnect switch is interposed within the first and second wires connected to the power source. A disconnect switch control circuit is connected to the sensing conductor for opening the disconnect switch upon the presence of a leakage current from the sensing conductor. The disconnect switch control circuit operates solely from the leakage current from the sensing conductor. | 01-28-2010 |
| 20090303642 | Leakage current detection and interruption circuit with improved shield - A circuit is disclosed for disconnecting a power source upon the detection of a leakage current comprising a power cable having an insulated first and a second wire. The power cable has a conductive shield surrounding the first and second wires with a drain wire electrically contacting the conductive shield. A disconnect switch is interposed between the power source and the power cable. A primary circuit controls the disconnect switch. A secondary circuit is connected to the drain wire for sensing a leakage current between the conductive shield and one of the first and second wires. An optical switch interconnects the primary circuit and the secondary circuit for opening the disconnect switch upon the secondary circuit sensing a leakage current. | 12-10-2009 |
| 20090251832 | Over heating detection and interrupter circuit - An over heating detection circuit and an interrupter circuit are disclosed for interrupting electrical power from a power source receptacle to a load upon the detection of an over heating condition of an electrical plug. A heat sensitive device monitors the temperature of the electrical plug. The over heating detection circuit is connected to the heat sensitive device for detecting an over heated condition in the electrical plug. The interruption circuit includes a disconnect switch connected to the over heating detection circuit for disconnecting electrical power upon the detection of the over heated condition in the electrical plug. | 10-08-2009 |
