Abstract: A duplex receptacle has a housing base with insulating wall elements to which a insulating circuit board supporting a surge suppressor circuit is fit. The surge suppressor can be preassembled and located as a compact unit in the housing with connective connections to each of the power conductors and ground. The device also has an insulated ground feature with each ground contact extending into housing base projections which have openings accommodating an isolated ground strap to which the internal ground contacts are joined. The features of the invention are well suited for shallow receptacles as may be fit within outlet boxes of a depth of no more than about 11/2 inches. In addition, a back insulating cover is provided that fits over the isolated ground strap and base projections. The back cover shields the ground strap.

Abstract: A duplex receptacle has a housing base with insulating wall elements to which an insulating circuit board supporting a surge supressor circuit is fit. The surge suppressor can be preassembled and located as a compact unit in the housing with connective connections to each of the power conductors and ground. The device also has an insulated ground feature with each ground contact extending into housing base projections which have openings accommodating an insolated ground strap to which the internal ground contacts are joined. The features of the invention are well suited for shallow receptacles as may be fit within outlet boxes of a depth of no more than about 11/2 inches.

Abstract: A whole house surge protector is provided in a single unit in association with a 4-wire wiring system with surge suppression between each of two hot conductors and respective neutral and ground conductors and also between the two hot conductors. The unit is in an insulating housing securable merely by a threaded nipple directly with a load center for protection on a multiplicity of circuit branches.

Abstract: A multiple outlet receptacle, such as one having four outlets in respective quadrants, is provided with a surge suppression circuit including a metal oxide varistor edgewise between the front and back of the device, other electronic elements, including dual status indicators, connected with an outer ring like contact plate and secured within portions of the insulating housings. Features for compactness and ease of assembly are provided. A pilot light indicator may alternatively be provided in receptacles without a surge suppressor utilizing some of the same components and assembly features.

Abstract: Surge suppression is provided by varistors connected between, respectively, hot and neutral conductors and hot and ground conductors, each through a common fuse that avoids hazardous overvoltages on the varistors. A first indicator circuit portion provides an indication that the power is on and surge protection is present and includes a first indicator device such as a green light-emitting diode that is energized when the fuse is intact, and a second indicator circuit portion is provided for indicating power is on and surge protection is lacking that includes a second indicator device such as a red light-emitting diode that is energized by the line conductors when the fuse has been interrupted. The surge suppressor and dual indicator apparatus can be contained within a wiring device such as a receptacle. A single varistor unit containing two varistor disks with three leads, including a center tap, allows three effective surge suppressor circuit branches in a compact configuration.

Abstract: Surge suppression is provided by varistors connected between, respectively, hot and neutral conductors and hot and ground conductors, each through a common fuse that avoids hazardous overvoltages on the varistors. A first indicator circuit portion provides an indication that the power is on and surge protection is present and includes a first indicator device such as a green light-emitting diode that is energized when the fuse is intact, and a second indicator circuit portion is provided for indicating power is on and surge protection is lacking that includes a second indicator device such as a red light-emitting diode that is energized by the line conductors when the fuse has been interrupted. The surge suppressor and dual indicator apparatus can be contained within a wiring device such as a receptacle. A single varistor unit containing two varistor disks with three leads, including a center tap, allows three effective surge suppressor circuit branches in a compact configuration.

Abstract: A receptacle with a ground fault circuit interrupter has a load contact and housing configuration in which a varistor for electronics protection is disposed with pressure contact to adjacent spring fingers of the load contacts. Also, a pre-assembly of molded plastic carrier elements supporting a sensing transformer, grounded neutral transformer, trip solenoid, and hybrid electronic circuit as a unit is disposed within the housing.

Abstract: A third pair of contacts, in addition to main power contacts, is provided that includes a conductive path through the latch member holding the power contacts in closed position and the latch member, being responsive to movement of the solenoid plunger operated from the trip coil, is the first of the three pairs of contacts to open upon a trip of the unit and is the first to be closed upon a resetting by manual force on the reset button.

Abstract: The mechanism is operable by a single test/reset push button whose initial travel from a normal operating position causes closing of test circuit contacts while power contacts are engaged. Upon an actual or test trip actuating the trip solenoid of the interrupter, a latch member releases a member holding movable power contacts and also extends the push button out due to spring action to indicate the occurrence of the trip. For resetting, the same button is again pushed to reengage the power contacts in a closed position after which release of the button returns it to its normal operating position in which the mechanism is latched.

Abstract: A ground fault circuit breaker including ground fault interruption means and overload interruption means that are independently responsive to open a common set of breaker contacts upon respective ground fault and overload conditions with a trip indicator visible external to the breaker that operates on actuation of the ground fault interruption means but not upon operation of the overload interruption means with means for electrically actuating the trip indicator upon occurrence of a ground fault condition that actuates the ground fault interruption means.

Abstract: Multipole ground fault circuit interrupter apparatus with a compensation network for maintaining a constant trip level despite less than all power poles being energized. The compensation network has matched resistors respectively connected to each power pole and an additional resistor connected to the common point of the matched resistors in a branch passing through the differential current transformer core from the load side to the supply side and connected to the neutral conductor, producing a desensitizing current when less than all poles are energized.

Abstract: Ground fault circuit breaker structure characterized by an insulating integral housing having a pair of side-by-side compartments that are separated by a partition wall. A circuit breaker is located in one compartment and a ground fault detector is located in the other compartment and isolated from the circuit breaker. The ground fault detector comprises a differential transformer comprising a current monitoring core, a plurality of primary windings on the core, each being one of a line and a neutral conductor of an A.C. electrical distribution system, a secondary winding sensing current unbalance between the primary windings, means responsive to a predetermined sensing signal to open the line conductor; and the line conductor extending between the circuit breaker trip means and through aperture means in the partition wall and through the magnetic core and back through the aperture means to the load terminal.

Abstract: A sensing amplifier of half wave sensitivity has its trip level effectively changed without internal adjustment in the sensing amplifier by a circuit branch connected between respective points on the hot line conductor and the neutral conductor across the differential transformer core and containing a resistance for causing additional current flow vectorially added to differential current otherwise occurring between the primary windings.

Abstract: An electric receptacle with ground fault protection characterized by an insulating housing of rectangular configuration adapted for mounting in a wall outlet box. The housing comprises opposite end and edge walls with front and rear sides open and with a transverse partition dividing a chamber formed by the ends and side walls into a pair of side-by-side compartments. Partition aperture means between the compartments and the first compartment communicating with the open front side and the second compartment communicating with the open rear side. At least one portion of the partition being nearer the front side than the remaining portions. Receptacle components are disposed in the first compartment and electronic components are disposed in the second compartment, and the components in each compartment are so disposed as to minimize the space requirements for the receptacle.

Abstract: The sensing and trip circuit electronics of a ground fault interrupter of the differential current transformer type is, in a two pole system, supplied with power from each of the line conductors through separate solenoid trip coils and zener diodes that together provide good transient suppression while the zener diodes together provide full wave rectification for the voltage supplied to the electronics.

Abstract: An electric receptacle with ground fault protection characterized by an insulating rectangular housing adapted for mounting in a wall outlet box. The housing comprises opposite end and edge walls with front and rear sides open and with a transverse partition dividing a chamber formed by the ends and side walls into a pair of side-by-side compartments. Partition aperture means between the compartments and the first compartment communicating with the open front side and the second compartment communicating with the open rear side. Receptacle components are disposed in the first compartment and electronic components are disposed in the second compartment, and the components in each compartment are so disposed as to minimize the space requirements for the receptacle.

Abstract: Ground fault circuit breaker structure characterized by an insulating integral housing having side-by-side compartments that are separated by partition walls. A circuit breaker is located in each of two compartments and a ground fault detector is located in a compartment between the circuit breakers and isolated from the circuit breakers by the partition walls.

Abstract: Ground fault interrupter apparatus of the differential transformer type is provided with an additional output transformer, the primary of which is connected between a line conductor and the neutral conductor of an A.C. system with a current limiting resistor adjacent the primary winding. The secondary of the output transformer is the neutral conductor. THe saturation properties of the core of the output transformer are such that during each half cycle a voltage pulse is induced in the secondary. The voltage pulse is of no consequence in the system during normal conditions but if a grounded neutral condition exists a current is produced in the neutral conductor unbalancing the differential transformer and interrupting operation.