Abstract: A method for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: providing a programmable relay protection system, including a plurality of relay devices on each line, programmed to include: monitoring of acceptable preset parameter ranges of at least three pairs electric operating conditions, that include at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence instantaneous overcurrent, zero sequence instantaneous overcurrent, and change in instantaneous undercurrent (and combinations thereof); permitting closed circuit operation when all of the lines show that the operating conditions are within the preset acceptable ranges; tripping a circuit breaker on a broken line when that line shows two operating conditions outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other

Abstract: A system for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: the transmission lines, a programmable relay protection system, including a plurality of existing low sensitivity (LS) relays and a corresponding set of high sensitivity (HS) relays in parallel with the is relays.

Abstract: A method for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: providing a programmable relay protection system, including a plurality of relay devices on each line, programmed to include: monitoring of acceptable preset parameter ranges of at least three pairs electric operating conditions, that include at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence instantaneous overcurrent, zero sequence instantaneous overcurrent, and change in instantaneous undercurrent (and combinations thereof); permitting closed circuit operation when all of the lines show that the operating conditions are within the preset acceptable ranges; tripping a circuit breaker on a broken line when that line shows two operating conditions outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other

Abstract: A system for preventing ground fault in a three-phase electric distribution line system caused by a line break, includes: the transmission lines, a programmable relay protection system, including high sensitivity. The HS relays on each line are programmed to include: preset acceptable operating parameter ranges of at least two electric operating conditions, namely, high sensitivity instantaneous undercurrent and at least one high sensitivity negative sequence overcurrent; monitoring; permitting closed circuit operation when all of the lines show that the two operating conditions are within the preset acceptable operating parameter ranges; tripping a circuit breaking device on a broken line when that line shows that the two operating conditions are outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other short circuit. A third parameter monitoring: rate of change in current is preferred.

Abstract: A method for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: providing a programmable relay protection system, including a plurality of relay devices on each line, programmed to include: preset parameter ranges of at least two electric operating conditions, at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence overcurrent (and combinations thereof), the preset ranges being acceptable operating parameter ranges; monitoring; permitting closed circuit operation when all of the lines show that the two operating conditions are within the preset acceptable operating parameter ranges; tripping a circuit breaker on a broken line when that line shows that the two operating conditions are outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other short circuit.

Abstract: The present disclosure pertains to detection of abnormal, risky, or abberant conditions in a power distribution network and to corresponding trip signals being used to trip open devices such as reclosers upstream of where the abnormal condition is detected. Detection of a missing broadband over power-line signal or of an open circuit between phases of a power distribution circuit may prevent severed conductors from causing a ground fault, therefore avoiding the possibility of fire and dangerous conditions.

Abstract: A system for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: the transmission lines, a programmable relay protection system, including a plurality of relay devices on each line, programmed to include: preset parameter ranges of at least two electric operating conditions, at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence overcurrent (and combinations thereof), the preset ranges being acceptable operating parameter ranges; monitoring; permitting closed circuit operation when all of the lines show that the two operating conditions are within the preset acceptable operating parameter ranges; tripping a circuit breaker on a broken line when that line shows that the two operating conditions are outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other short circuit.

Abstract: A system for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: the transmission lines, a programmable relay protection system, including a plurality of existing low sensitivity (LS) relays and a corresponding set of high sensitivity (HS) relays in parallel with the is relays.

Abstract: A system for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: the transmission lines, a programmable relay protection system, including a plurality of relay devices on each line, programmed to include: preset parameter ranges of at least two electric operating conditions, at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence overcurrent (and combinations thereof), the preset ranges being acceptable operating parameter ranges; monitoring; permitting closed circuit operation when all of the lines show that the two operating conditions are within the preset acceptable operating parameter ranges; tripping a circuit breaker on a broken line when that line shows that the two operating conditions are outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other short circuit.

Abstract: A method for preventing ground fault in a three-phase electric transmission line system caused by a line break, includes: providing a programmable relay protection system, including a plurality of relay devices on each line, programmed to include: preset parameter ranges of at least two electric operating conditions, at least one high sensitivity instantaneous undercurrent and at least one high sensitivity condition selected from line differential overcurrent and negative sequence overcurrent (and combinations thereof), the preset ranges being acceptable operating parameter ranges; monitoring; permitting closed circuit operation when all of the lines show that the two operating conditions are within the preset acceptable operating parameter ranges; tripping a circuit breaker on a broken line when that line shows that the two operating conditions are outside the preset parameter ranges; and shutting down power to the broken line before it otherwise causes a ground fault or other short circuit.

Abstract: A dual-tire foreign-object removing apparatus includes a web which is trainable about a foreign object lodged between dual vehicle tires, a rod for applying a pulling force to the web and the foreign object and a reaction element which provides a stand-off from the tires for the rod.

Abstract: The safety strap of the invention includes a fastener which is secured to a snowboard, and a length of cable, having a loop at each end thereof. One of the loops is secured to the fastener while the other end has an attachment device secured to it. A leg strap is worn by a snowboard user. The strap is secured about the user's leg and has a connection thereon for receiving the attachment device at the other end of the cable.

Abstract: A locking device for skis or the like comprises two lengths of cable having loops formed at their remote ends and an intervening length of chain. By inserting the free ends of the cables through appropriate links in the chain and thereafter locking the free ends together, the size of the loops can be adjusted so that objects to be locked together can be snugly embraced by the opposite cable lengths.

Abstract: A silencer quiets the exhaust output from a marine engine by injecting a spray of cooling water into the exhaust passageway to mix with and cool the exhaust gases before output from the passageway. The exhaust passageway preferably enlarges substantially in cross-sectional area in the region where the mixing occurs between the injected water and the exhaust gases for enhancing the cooling effect. An inlet scoop receives water as the boat moves forward, and the water is forced through a line and into the exhaust passageway in a way that breaks the water into drops for contacting and cooling the exhaust gases. A mute that is preferably conical in shape and centered in the exhaust outlet also cooperates to reduce the exhaust noise.

Abstract: A deep-V tunnel stern boat has the forward portion of the tunnel shaped for uniformly distributing the resurgent flow across the width of the tunnel and for smoothly forming the entrance curve to the tunnel to optimize a suction tending to lift the water into the tunnel. This is done by recessing port and starboard halves of the tunnel into the sides of the hull bottom so the tops of the tunnel halves are approximately parallel with the sides of the hull bottom at the deep-V angle and meet at an obtuse angle above the keel line. The tops of the tunnel halves are gradually shaped into a semi-cylinder around the upper half of the propeller, the tunnel sides are flared outward aft of the propeller, and exhaust ports are located in the flared tunnel sides. Such tunnels are also adapted for twin tunnel stern boats.