Disclosed is a system that reduces fault currents in a power grid, thereby reducing the risk of unintentionally igniting a fire when an object comes in proximity to a high voltage power line. The circuit comprises an isolation transformer, a neutral connection, a current compensating device, and an automatic recloser or other circuit interrupting type protection system. The isolation transformer may comprise a delta-delta or delta-zigzag transformer with a one-to-one ratio between the input and output voltages and phase angle. The current compensating device is connected to the neutral and configured to redirect a substantial portion of a fault current to ground through the isolation transformer neutral instead of the fault itself. The current compensating device may comprise an arc suppression coil tuned to match the capacitance of the three phase outputs, or an inverter.

An electronic barrier device includes an Isolating Barrier or a Zener Barrier with a voltage limiter or voltage shunt such as at least one zener device for voltage limitation in a circuit during a fault condition. The barrier device includes a crowbar device arranged to latch across the at least one voltage shunt device to reduce power dissipation in the at least one voltage shunt device in the circuit fault condition. The crowbar device is arranged to latch responsive to a change in a current flowing in the barrier device.

A limiter having a more ideal limiting function, a short response time, and an adjustable limiting threshold. In one embodiment, a self-activating limiter stack is coupled between circuit ground and a signal line between a source and a receiver. The limiter stack limits the power from the source when the voltage on the signal line exceeds the breakdown voltage of the limiter stack. The threshold of the limiter stack is controlled in part by a first control voltage applied to a control input. A rectifying power detector circuit connected between a node on the signal line and the control input of the limiter stack provides a second control voltage as a function of the signal power at the node. The combined first and second control voltages are applied to the control input to modulate the ON resistance of the limiter stack, thereby limiting the leakage power reaching the protected receiver.

The present invention provides for an electronic isolator device such as a universal isolator and having isolation and possible safety functionality and comprising an isolator module (550), and a base module (500), and wherein the isolator module is arranged for removable physical/electrical connection to the base module and in at least two orientations/positions relative to the base module, wherein electrical connection to the base module in each of the at least two orientations/positions serves to configure the type/functionality of the isolator device.

A laser spectrometer can be operated for analysis of one or more analytes present in a combustible gas mixture. The spectrometer can include one or more features that enable intrinsically safe operation. In other words, electrical, electronic, thermal, and/or optical energy sources can be limited within an hazardous are of the spectrometer where it is possible for an explosive gas mixture to exist. Methods, systems, articles and the like are described.

A DC and/or an AC power transmission circuit protection system is for protection of a cabling medium. The circuit protection system includes a power supply, a powered device and a circuit protection module that includes an over-current and/or over-voltage circuit module and/or a heat circuit protector. The protection system is disposed between the power supply and the powered device, and interrupts an electrical current that flows through the cabling medium when the over-current and/or over-voltage circuit module and/or the circuit protector exceeds a predetermined level. There is also provided a method to dispose the circuit protection system and the circuit protection module within the circuit and to interrupt the circuit when over-current and/or over-voltage circuit module and/or heat circuit protector exceeds a predetermined level.

A device, battery and method for spark detection based on transient currents is provided. The battery includes: a cell; an interface; a first protection circuit and a second protection circuit. The first protection circuit comprises a first switch between the cell and the interface. The second protection circuit comprises a second switch between the cell and the interface. The first protection circuit is configured to: measure a load current on the cell; and open the first switch according to a first delay time based on the measurement of the load current. The second protection circuit is configured to: measure a transient current on the cell above the load current; and open the second switch according to a second delay time, lower than the first delay time, based on the measurement of the transient current.

A wireless sensor network gateway includes safe side circuitry, hazardous side circuitry and isolation circuitry, which are supported by a housing. The safe side circuitry includes a safe side power circuit, and a safe side data input/output (I/O) circuit. The hazardous side circuitry includes a hazardous side power circuit, and a hazardous side data I/O circuit. The isolation circuitry divides the safe side circuitry from the hazardous side circuitry. The isolation circuitry includes a power isolation circuit that couples the safe side power circuit to the hazardous side power circuit and forms an intrinsic safety barrier between the safe side power circuit and the hazardous side power circuit, and a data isolation circuit that couples the safe side data I/O circuit to the hazardous side data I/O circuit and forms an intrinsic safety barrier between the safe side data I/O circuit and the hazardous side data I/O circuit.

A wireless sensor network gateway includes safe side circuitry, hazardous side circuitry and isolation circuitry, which are supported by a housing. The safe side circuitry includes a safe side power circuit, and a safe side data input/output (I/O) circuit. The hazardous side circuitry includes a hazardous side power circuit, and a hazardous side data I/O circuit. The isolation circuitry divides the safe side circuitry from the hazardous side circuitry. The isolation circuitry includes a power isolation circuit that couples the safe side power circuit to the hazardous side power circuit and forms an intrinsic safety barrier between the safe side power circuit and the hazardous side power circuit, and a data isolation circuit that couples the safe side data I/O circuit to the hazardous side data I/O circuit and forms an intrinsic safety barrier between the safe side data I/O circuit and the hazardous side data I/O circuit.

A hot swapping protection device for Power over Ethernet which has a state setting switch group, an interface circuit, a power supply device, a packet switching controller, multiple isolation coil sets, and multiple connectors. The packet switching controller receives a digital state value P2 of the interface circuit and a digital signal P1 of the state setting switch group and bitwise compares P1 and P2 so as to output a command to control the DC voltage outputs of the power supply device. The power supply device has a digital power controller and an analog power controller having multiple voltage output terminals for providing DC voltages to the multiple connectors. Before removing a cable connected to a connector, all voltage output states of the voltage output terminals corresponding to the connector are set to a cutoff state, so that sparks generation can be avoided during subsequent cable plug-in and unplugging.