Matches 51 - 100 out of 253 < 1 2 3 4 5 6 >
Match Document Document Title
5633540 Surge-resistant relay switching circuit  
In a relay switching panel, a switching circuit operates to selectively connect and disconnect resistive, capacitive and inductive loads to an AC power source with substantially no arcing. The...
5598311 D.C. breaker arc extinguishing circuit  
A circuit for preventing ionization of air between contact points of a DC breaker switch when the breaker switch is opened includes a capacitor connected through a diode to form a shunt between the...
5576919 Spark suppressor circuit for protection of an electrical switch, and electrical thermal appliance comprising such a circuit  
A spark suppressor circuit (1) is provided for protection of an electrical switch (4) which in series with a load (2) is connected between a first supply voltage terminal (8) and a second supply...
5563541 Load current detection circuit  
A load current detection circuit restrains the generation of noise spikes with a minimum of circuitry when changing between current detection sensitivity ranges by providing a plurality of...
5548461 Arc suppressor  
Placed in electrical circuit in shunt of the electrodes that supply current to a protected device and optically coupled to the location in the protected device where an electric arc is most likely...
5536980 High voltage, high current switching apparatus  
A high voltage, high current DC switch is shown having a single pole, double throw relay and a solid state power switch such as an IGBT or MOSFET transistor. Voltage is switched by means of the...
5528443 Hybrid switch using a one-shot firing pulse  
Semiconductor switching elements (inverse-parallel connected thyristors) of each main circuit element unit are connected in parallel to a main contact of an electromagnetic contactor. An operation...
5452170 Commutation type DC breaker  
A commutation type DC breaker having a commutation circuit electrically connected in parallel to a main contact. The main contact is connected between a DC power supply and a load. The commutation...
5428195 Current limiter unit for molded case circuit breakers  
A self-contained current limiter unit allows lower short-circuit-rated circuit breakers to be utilized within industrial applications. The unit is electrically-connected in series with the circuit...
5406442 Solid state relay  
A solid state relay having circuitry incorporated therein which senses line conditions and load conditions and activates an alarm when a fault is detected.
5406128 Multicircuit control apparatus and control method therefor  
In a multicircuit control apparatus (10) including a mechanical main contact (125) and plural semiconductor switching devices such as triacs (13a, --, 13d) each connected in series to the main...
5283706 Switching circuit  
An electrical switching circuit comprising an electromagnetic relay and a bye directively controlled contactless switch. The electrical switching circuit being able to make and break a capacitive,...
5233495 Device for protecting against operational overloads, at opening, for static relays with semi-conductors  
A device for protecting a principal static relay including semi-conductors from overloads which includes an auxiliary static relay which is connected in series with a conventional parallel...
5193041 Electrical current interrupter  
An electrical circuit interrupter for connection between two conductors has a first fixed contact electrically directly connected to one of the conductors, a second fixed contact adjacent the first...
5164872 Load circuit commutation circuit  
Arrangement for arcless interruption of a-c load current in response to a current interruption command. Separable contact means serially connected with controlled impedance means, and parallel...
5151840 Switch protection circuit  
A circuit for the protection the contacts of a switch device such as a reed switch when used in a control circuit. The protection circuit isolates the switch contacts from the load it is...
5124872 High tension circuit breaker having varistors  
A high tension circuit breaker comprising at least one circuit-breaking chamber and, in parallel with the circuit-breaking chamber, firstly a varistor in series with an interrupter, and secondly a...
5083232 Fault current limiter  
A fault current limiter according to the invention comprises a contact device (K) to the contacts of which is connected a resistor/inductor combination comprising a series connection of a first...
5081558 High voltage DC relays  
A high voltage DC relay with arc suppression in which a MOSFET in parallel with the relay contacts is turned on during contact break mode by the controlled discharge of a capacitor between the...
5053907 Hybrid relay  
A hybrid relay comprising a mechanical relay provided with mechanical contact unit adapted to be actuated by an electromagnet, an electronic relay consisting of a semiconductor device, and a drive...
5006784 Thyristor on-load change-over switch  
The invention relates to an arrangement in an on-load change-over switch of an on-load tap changer for uninterrupted switch-over of the regulating winding of a transformer. On-load change-over...
4992904 Hybrid contactor for DC airframe power supply  
A contactor (12) for controlling connection of a DC power supply to an electrical load (14) in includes a series circuit (19) disposed between a nonground DC potential and a load having first (20)...
4959746 Relay contact protective circuit  
A contact protective circuit for a relay detects a transient in the relay operating coil and turns on a low resistance power MOSFET in shunt relation with the contacts before the contacts close or...
4920448 Semiconductor-assisted ultra-fast contact breaker  
An ultra-fast contact breaker is described which includes an ultra-fast cut-off mechanism provided with a repulsion disk fitted with moving contacts (7, 7'), the said mechanism also including fixed...
4885654 Device for arcless switching of electrical circuits  
A device for arcless switching of electrical circuits, wherein power leads of a controlled semiconductor device - transistor 9 are connected parallel to a movable contact (2) and a fixed make...
4885657 Thyristor with turn-off facility and overvoltage protection  
In a thyristor with turn-off facility (AT) and overvoltage protection, the voltage limitation is achieved by a parallel-connected controllable resistor, in particular in the form of a J-FET (JF)...
4860156 Overvoltage protective circuit  
A trigger circuit for a spark gap chain with at least two series-connected spark gaps, of which at least one is provided with at least one trigger electrode, includes a resistor chain which is...
4855612 Switching current and a relay device employed therein  
A switching circuit for supplying electric power to a load from a power source includes a first relay device having a first switch and a semiconductor switching element connected in series with the...
4847719 Apparatus and method for protecting the contacts of an electrical switch from current surges  
The contacts of an electrical switch, such as a magnetic contact reed switch or a magnetic contact reed relay used in a burglar alarm system, are protected from being fused together by transient...
4829457 Overload protection circuit for solid state switch  
A control device for energization of a load employs a bidirection triggerable solid state switching device connected in series with an alternating current power source and the load. In order to...
4816958 Fault current interrupter including a metal oxide varistor  
An electric protection apparatus is provided for protection against current faults of different intensities, including, in series in an internal circuit, a first switch with automatic opening,...
4811163 Automatic power bus transfer equipment  
A circuit for protecting the power contacts (18, 20) of automatic bus transfer equipment, including high speed solid state switches (30, 32) connected across the respective contacts. A timing and...
4805062 DC circuit breaker and method of commutation thereof  
A DC circuit breaker and a method of commutation during a commutation capacitor capable of being directly charged from a main DC line are disclosed. A breaker unit is inserted in a main DC line and...
4802051 Arc-free electromagnetic contactor  
An electromagnetic contactor without arc generation wherein the silver contacts are omitted by providing contact portions between the fixed terminals and the movable piece to separate the...
4788415 Dual bimetal power control switching arrangement for electronically controlled appliances  
A power control switching arrangement for controlling energization of a load in response to an external controller, in which a first semiconductor switch is connected in parallel with the series...
4780622 Apparatus for reducing stresses that initiate restrike of breakers in disconnecting capacitor banks  
Re-strike in the circuit breaker of a capacitive load applied across an AC voltage power supply is reduced or avoided by connecting across the capacitor bank a tuned discharge circuit. The tuned...
4772809 Switching circuit and a relay device employed to prevent arcing  
A switching circuit for supplying electric power to a load from a power source includes a first relay device having a first switch and a semiconductor switching element connected in series with the...
4764836 Circuit breaker  
The circuit breaker displays a commutation device (4) and a semiconductor valve arrangement (6) which is connected in parallel with the commutation device (4), an isolating switching point (5)...
4760483 Method for arc suppression in relay contacts  
In a circuit having an electro-mechanical relay, the contacts of which are subject to arcing, bridging across the electro-mechanical relay in a manner configured to begin conducting electrical...
4754360 Arc extinguishing apparatus having sensing of initial arc  
An apparatus for extinguishing the arc which occurs between a pair of electrodes separated in the switchgear when the high voltage loaded switchgear is opened. The earliest arc is detected which...
4749934 Intrinsically safe battery circuit  
An intrinsically safe battery circuit for connection between a battery and a load, such as a hand held transceiver, referred to as "HT's". The circuit includes a minor current path through a...
4745511 Means for arc suppression in relay contacts  
In a circuit having a electro-mechanical relay the contacts of which are subject to arcing, a shunt across the electro-mechanical relay configured to begin conducting electrical current across the...
4733031 Switching apparatus protected against short circuit currents  
A contactor apparatus is provided protected against short circuit currents, comprising for each phase between input and output terminals a contactor switch and a protective switch with automatic...
4723187 Current commutation circuit  
Load current is diverted from a circuit breaker, when it is opened, through a commutation circuit. The latter has a capacitor, inductance and solid state switch serially connected with the output...
4704652 Hybrid electrical power controller  
A hybrid electrical power controller is provided with a relay having a coil and a pair of mechanical contacts. A solid state switching device is electrically connected in parallel with the...
4700256 Solid state current limiting circuit interrupter  
A solid state current limiting circuit interrupter for the arcless interruption of current through a protected circuit includes a pair of mechanically switched contacts electrically connected in...
4695913 Shunt effect low voltage circuit breaker  
A circuit breaker, notably breaking the phase and neutral circuit, contains a shunt circuit, constituted by a switching electrode disposed in proximity to the phase contacts to pick up an arc drawn...
4658320 Switch contact arc suppressor  
An arc suppression circuit for a switch carrying a load current includes a MOSFET having a drain connected to a first contact of the switch and a source connected to a second contact of the switch....
4636906 Solid state circuit interruption employing a stored charge power transistor  
A solid state circuit interrupter utilizes a power transistor connected across a pair of separable contacts to eliminate contact arcing between the contacts upon circuit interruption. Stored charge...
4636907 Arcless circuit interrupter  
Arcless circuit interruption from metallic contacts is accomplished by the combination of a solid state current interrupter with a control circuit and an impedance circuit. The impedance circuit...
Matches 51 - 100 out of 253 < 1 2 3 4 5 6 >