| Patents for H02H 7 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions (32,726) |
|---|
| 04/26/1989 | EP0313366A2 Variable speed constant frequency power system with boost converter auxiliary output |
| 04/26/1989 | CN2036725U Power supply for electric elevator controls |
| 04/26/1989 | CN2036715U Voltage-regulator of no-excitaion ac generator |
| 04/25/1989 | US4825350 Method and apparatus for detecting a reduction in the input voltage to a power supply |
| 04/25/1989 | US4825327 Negative and zero sequence directional overcurrent unit for AC power transmission line protection |
| 04/25/1989 | US4825326 Digital calculation type differential relay |
| 04/25/1989 | US4825323 For detecting power swings |
| 04/19/1989 | EP0311776A2 Protection circuit for limiting the speed of a washing machine motor |
| 04/19/1989 | CN2036326U Coal isolation mine illuminating comprehensive protecting switch |
| 04/19/1989 | CN2036325U Protection switch for electric motor lacking phase |
| 04/19/1989 | CN2036324U Metallic thermal resistance type over load and heat protector for electric motor |
| 04/18/1989 | US4823251 Controller for instantaneous output current and/or voltage of 3-phase converter |
| 04/18/1989 | US4823247 Stabilized power supply unit |
| 04/18/1989 | US4823057 Variable speed motor control |
| 04/12/1989 | EP0311355A2 Electric motor controllers |
| 04/12/1989 | CN2035939U Automatic microcomputer controller for generator load |
| 04/12/1989 | CN2035927U Automatic graond protector |
| 04/11/1989 | US4821137 Positive sequence distance relay for AC power transmission line protection |
| 04/11/1989 | US4821136 Power transistor with self-protection against direct secondary breakdown |
| 04/06/1989 | DE3831142A1 Solar pump system |
| 04/05/1989 | EP0309814A1 Electric energy generation device |
| 04/04/1989 | US4819123 Compressed air supply system |
| 04/04/1989 | US4819122 Over-current timer modulator |
| 04/04/1989 | US4819121 Security apparatus for power converter |
| 04/04/1989 | US4819118 Electromagnetic contactor tandem control system for thermal protection of a bidirectional motor drive |
| 04/04/1989 | US4819046 Integrated circuit with improved protective device |
| 03/30/1989 | DE3829955A1 Ortungsgeraet zur ortung von stoerungen eines elektrostrom-uebertragungssystems Ortungsgeraet for identification of faults of an electromagnetic flow-uebertragungssystems |
| 03/29/1989 | EP0309255A1 Apparatus and process for detecting direct current magnetic flux deflections of an electrical transformer |
| 03/29/1989 | EP0309254A1 Apparatus and process for detecting direct current magnetic flux deflections of an electrical transformer |
| 03/29/1989 | EP0308634A1 Power supplies for electroluminescent lamps or panels |
| 03/29/1989 | CN2035153U Electrostatic-induction type fault-protector for high-voltage switch |
| 03/28/1989 | US4816962 Uniform magnetic field coil |
| 03/28/1989 | CA1251843A1 Door or gate obstruction control |
| 03/23/1989 | DE3730829A1 Overload protection for the excitation circuit of a synchronous machine |
| 03/22/1989 | CN2034748U General three-safety generator with phase-failure protector |
| 03/22/1989 | CN2034747U Three-phase motor protector against phase interruption |
| 03/21/1989 | US4815052 Automatic overvoltage protection circuit |
| 03/21/1989 | US4814932 Device for protection against short circuits for AC networks and current limiting circuit breaker appropriate for such a device |
| 03/21/1989 | US4814699 Method for partial discharge detection and breaking spark measuring in dynamo-electric high-voltage machines, and an apparatus for performing the method |
| 03/21/1989 | US4814675 Device limiting the power supply current for a direct current motor equipped with such a device |
| 03/15/1989 | CN2034342U Safety button for protecting phase interruption of three-phase motor |
| 03/15/1989 | CN2034341U Protector for excessive load and phase interruption of ac motor |
| 03/15/1989 | CN2034337U Three phase electric shock protector for electric machine |
| 03/14/1989 | US4812995 Digital distance relaying on electric power transmission |
| 03/14/1989 | US4812796 Quench propagation device for a superconducting magnet |
| 03/14/1989 | US4812729 Protecting apparatus for secondary excitation type variable speed AC generator/motor |
| 03/08/1989 | CN2033956U Apparatus for the prevention of back-flow current from network to electric power generating set |
| 03/07/1989 | US4811184 Switch-mode power supply with dynamic adjustment of current sense magnitude |
| 03/07/1989 | CA1250941A1 Programmed overexcitation protective relay and method of operating the same |
| 03/07/1989 | CA1250929A1 Apparatus for controlling rotational speed of radiator fan |
| 03/02/1989 | DE3727498A1 Device for controlling the power of an electrical load |
| 03/01/1989 | CN2033557U Current-limiting, overcurrent, overvoltage protector of regulated power supply |
| 02/28/1989 | US4809122 Self-protective fuel pump driver circuit |
| 02/28/1989 | US4808905 Current-limiting circuit |
| 02/28/1989 | US4808902 Control apparatus for brush-less motor |
| 02/28/1989 | CA1250617A1 Energy economizer controlled-current start and protection for induction motors |
| 02/22/1989 | EP0304196A2 Electric motor armature current control circuit |
| 02/22/1989 | CN2033164U Loss of phase electronic protecter for three-phase nonsynchronous motor |
| 02/21/1989 | US4807084 Superconducting magnet apparatus with emergency run down unit |
| 02/21/1989 | US4806925 Infrared signalling system for detecting a predetermined state of a high voltage device |
| 02/21/1989 | US4806839 Device for energizing a hermetic motor using inverter |
| 02/15/1989 | EP0303171A2 A variable speed generator-motor apparatus |
| 02/15/1989 | CN2032774U Voltage type protector for short-phase of ac electric machine |
| 02/09/1989 | WO1989001255A1 Self-protective fuel pump driver circuit |
| 02/07/1989 | US4803635 Information data output device for electric-power systems |
| 02/07/1989 | CA1249756A1 Pump monitor for photoactivation patient treatment system |
| 02/01/1989 | EP0301055A1 Protective device for electrically driven apparatus |
| 02/01/1989 | CN1030732A Safety devices for elevator |
| 01/31/1989 | CA1249652A1 Sudden pressure relay supervisory apparatus |
| 01/31/1989 | CA1249621A1 Switching apparatus protected against short-circuit currents |
| 01/25/1989 | CN1030675A Gate signal generator for thyristor valve |
| 01/24/1989 | US4800324 Brush motor amplifier with overspeed protection |
| 01/24/1989 | CA1249338A1 Voltage detecting apparatus for variable-frequency power system |
| 01/24/1989 | CA1249337A1 Line protection |
| 01/19/1989 | DE3723067A1 Method for operating a converter |
| 01/18/1989 | EP0299325A1 Actively shielded supraconducting magnet of a nuclear spin tomographic apparatus |
| 01/18/1989 | EP0299281A1 Power supply protection circuit for the excitation or des-excitation of a superconducting magnet coil |
| 01/18/1989 | EP0087424B1 Inverter connection with bridge for transforming direct current into single phase or multiphase alternating current |
| 01/18/1989 | CN1030502A Electromagnetic sensing type protection principle for 3-phase motor |
| 01/18/1989 | CN1030501A Three-phase phase-sequence identification controller with loss-of-phase and overload protection |
| 01/11/1989 | EP0298935A1 A method and arrangement for protecting turbine generators against subsynchronous resonances occuring in power transmission systems |
| 01/11/1989 | EP0298515A1 Gate signal generator for thyristor valve |
| 01/11/1989 | CN2030773U Overhead power line wire-breakage automatic controller |
| 01/11/1989 | CN2030772U Full-automatic protective arrangement for motor |
| 01/10/1989 | US4797800 Power regulating system for an engine generator |
| 01/05/1989 | DE3719956A1 Device and method for blocking detection |
| 01/04/1989 | EP0297421A2 By-pass element for protection of battery cells |
| 01/04/1989 | CN2030390U Electricty-saving swtich with phase-failure protecting device |
| 01/04/1989 | CN2030389U Three-phase ac intelligent controller |
| 01/03/1989 | US4796146 Protection circuit for a thyristor converter |
| 01/03/1989 | CA1248179A1 Protected input/output circuitry for a programmable controller |
| 12/29/1988 | WO1988010532A1 Load control system |
| 12/29/1988 | WO1988010528A1 Shorted-coaxial-cable detector for local-area networks |
| 12/21/1988 | EP0295415A2 Circuit for protection against fault currents |
| 12/21/1988 | CN87215806U Electricity-economizing protector of electric motor |
| 12/20/1988 | US4792735 Apparatus for adjusting torque and speed of a dentist handpiece D.C. motor |
| 12/20/1988 | CA1247225A1 Protective relaying apparatus for providing fault- resistance correction |
| 12/20/1988 | CA1247172A1 Fusible link |
| 12/19/1988 | EP0205596A4 Pump control apparatus and method. |
| 12/14/1988 | EP0295234A1 Process and device for protecting and monitoring transformer-fed electrical installations and the transformer itself |