Abstract: A test verification circuit is described herein for verifying proper operation of a tested circuit, such as a voltage hazard warning circuit, using an N-channel MOSFET configured for switching ON and OFF the test verification circuit during a power outage, and a voltage source that provides an input voltage to the N-channel MOSFET from a conserved power supply. The N-channel MOSFET provides temporary power from a conserved power supply to the test verification circuit upon activation by a user during a power outage, and the test verification circuit determines whether the tested circuit has been de-energized, remains energized, or there remains inadequate power to complete the test.

Abstract: A test verification circuit is described herein for verifying proper operation of a tested circuit, such as a voltage hazard warning circuit, using an N-channel MOSFET configured for switching ON and OFF the test verification circuit during a power outage, and a voltage source that provides an input voltage to the N-channel MOSFET from a conserved power supply. The N-channel MOSFET provides temporary power from a conserved power supply to the test verification circuit upon activation by a user during a power outage, and the test verification circuit determines whether the tested circuit has been de-energized, remains energized, or there remains inadequate power to complete the test.

Abstract: A test verification circuit is described herein for verifying proper operation of a tested circuit, such as a voltage hazard warning circuit, using an N-channel MOSFET configured for switching ON and OFF the test verification circuit during a power outage, and a voltage source that provides an input voltage to the N-channel MOSFET from a conserved power supply. The N-channel MOSFET provides temporary power from a conserved power supply to the test verification circuit upon activation by a user during a power outage, and the test verification circuit determines whether the tested circuit has been de-energized, remains energized, or there remains inadequate power to complete the test.

Abstract: A test verification circuit is described herein for verifying proper operation of a tested circuit, such as a voltage hazard warning circuit, using an N-channel MOSFET configured for switching ON and OFF the test verification circuit during a power outage, and a voltage source that provides an input voltage to the N-channel MOSFET from a conserved power supply. The N-channel MOSFET provides temporary power from a conserved power supply to the test verification circuit upon activation by a user during a power outage, and the test verification circuit determines whether the tested circuit has been de-energized, remains energized, or there remains inadequate power to complete the test.

Abstract: An electrical safety monitor for monitoring electrical energy potentials of one or more electrical power input lines of an A.C. circuit. The electrical safety monitor including one or more detector circuits, each including one or more capacitors corresponding to one or more electrical power input lines arranged to charge responsive to an electrical energy potential on the corresponding line and a discharge circuit electrically communicating with the one or more capacitors to cause a capacitor discharge at a predetermined capacitor voltage. A plurality of solid-state light-emitting devices disposed in a human-viewable arrangement, each light emitting device electrically communicating with a selected capacitor and producing a light output responsive to capacitor discharge of the corresponding capacitor. A testing circuit generates a test current through the one or more detectors circuits providing verification of the electrical safety monitor integrity.

Abstract: An electrical safety monitor (20) includes a housing (50) with a display face (70) and a securing section (54) that connects with an electrical panel (62). Electrical circuitry (30) is contained in the housing (50). The electrical circuitry (30) communicates with electrical lines (L1, L2, L3, GND) of the panel (62), and defines high impedance electrical paths between pairs of electrical lines (L1, L2, L3, GND). Each high impedance path includes a positive light emitting diode (D1, D2, D3, D4) arranged to draw current from a line carrying a positive electrical energy potential and a negative light emitting diode (D5, D6, D7, D8) arranged to draw current from a line carrying a negative electrical energy potential relative to the positive electrical energy potential. The positive and negative light emitting diodes are disposed on the display face (70) of the housing (50). Each light emitting diode produces light responsive to current flow in a high impedance path that includes the light emitting diode.

Abstract: A laser diode (22) emits laser light which is collimated into parallel rays with a collimating lens (24). The collimated beams travel about 5 to 50 cm before being reflected back to an adjustable mirror (28), to a fixed mirror (30), and then on to a photoreceiver (34). The adjustable mirror (28) is pivoted by turning an adjusting screw (40). The adjustable mirror (28) has a toothed cam (48) on its backside that mate with the threads of the adjusting screw (40). When the adjusting screw (40) is turned, it forces the cam to move with it, thus changing the angle of the adjustable mirror (28). A ball lens (32) focuses the reflected light onto the photoreceiver (34). The photoreceiver (34) and laser diode (22) are synchronized so that the receiver (34) can only receive light during appropriate windows of time corresponding to when the laser light was emitted.

Abstract: A laser diode (22) emits laser light which is collimated into parallel rays with a collimating lens (24). The collimated beams travel about 5 to 50 cm before being reflected back to an adjustable mirror (28), to a fixed mirror (30), and then on to a photoreceiver (34). The adjustable mirror (28) is pivoted by turning an adjusting screw (40). The adjustable mirror (28) has a toothed cam (48) on its backside that mate with the threads of the adjusting screw (40). When the adjusting screw (40) is turned, it forces the cam to move with it, thus changing the angle of the adjustable mirror (28). A ball lens (32) focuses the reflected light onto the photoreceiver (34). The photoreceiver (34) and laser diode (22) are synchronized so that the receiver (34) can only receive light during appropriate windows of time corresponding to when the laser light was emitted.

Abstract: A laser diode (22) emits laser light which is collimated into parallel rays with collimating lens (24). The collimated beams travels as much as 50 meters or more before being reflected back to a photoreceiver (28). A ball lens (26) focuses the reflected light onto the photoreceiver. The photoreceiver, preferably, is a synchronous detector which issues control pulses to a laser drive circuit (42) for causing the laser diode to emit intermittent bursts of laser light. The synchronous detector then compares the timing of received light with the timing of the control pulses to the laser diode to distinguish between true reflected light and stray light. An intensity adjustment (56) adjusts the intensity of the laser light in accordance with a distance between the laser diode/photoreceiver and a reflector. In this manner, distances of 1-70 meters can be accommodated with no lens modification.

Abstract: There is disclosed a multi-phase fuse status indicator having a green "good" and a red "bad" indicator LED for each line fuse of the respective phases, the current to the LED's being pulsed to cause them to provide a blinking indication. Power used for the logic circuit for the LED's and the LED's themselves and the related heat dissipation is less than 10 watts and is supplied from the power lines connected through the fuses regardless of the fuses' condition. Only two simple conductor connections are required from the fuse status indicator to each fused line of the multi-phase power system.