An electrical feedback barrier is configured to safely interconnect an intrinsically safe power supply to a non-intrinsically safe electrical load device in a hazardous environment. Electrical feedback from the non-intrinsically electrical load device is blocked by the electrical feedback barrier to protect the intrinsically safe power supply from adverse operating conditions. The electrical feedback barrier and the electrical load device are enclosed in an explosion-proof or flameproof enclosure for compliance with electrical equipment safety standards in the hazardous environment.

Apparatus and associated methods relate to providing safe electrical power to electrical equipment operating in a hazardous location. Safe electrical power is power that is both current limited and voltage limited so as to provide insufficient energy to ignite flammable gas or dust of a hazardous location. Safe electrical power is provided by first limiting voltage of operating power provided by a power source. Then the voltage-limited operating power is current limited by a current-limiting device. The current and voltage limited operating power is then converted to a step-down power via a current-limiting network. The step-down power is then voltage limited by a second voltage-limiting device. In some embodiments, the current-limiting network is a current mode step-down regulator.

A package has a package body formed by stacked insulating layers and having a front surface including a mounting area, a back surface and a side surface; a plurality of hollow portions arranged so as to be adjacent to each other on the front surface of the package body; a plurality of electrode pads individually placed on respective bottom surfaces of the hollow portions; and a partition wall formed by at least one insulating layer that forms the package body and having protruding banks at its both edge sides. Surfaces of the electrode pads are located at a lower position with respect to the front surface of the package body. The hollow portions are arranged at opposite sides of the partition wall. The electrode pads are electrically connected to respective conductor layers that are formed on the back surface and/or the side surface of the package body.

Compliant electrical circuit protection devices are described for use in hazardous environments without presenting ignition risks for potentially explosive environmental conditions. Sensing features and systems may evaluate wiring limits and user selected settings for compatibility, detect loose connections and operating parameters to ensure safe operation of the device, and to intelligently diagnose and manage issues of concern for the circuit protection devices as well as the larger electrical power system.

Hazardous location compliant solid state circuit protection devices include safety lockout components ensuring disconnection as a safeguard in the completion of power system maintenance and service tasks by responsible personnel. The safety lockout components may include a mechanical lockout interfacing with a physical lock element, an electrical lockout implemented through the controls of the solid state circuit breaker device, and combinations thereof. Visual device feedback and confirmation may be provided to personnel that the lockouts have been successfully activated, as well as successfully deactivated to reconnect and restore operation of the load side circuitry.

A simple, low-cost circuit is disclosed that provides the requisite triple redundancy for a spark protection circuit for a battery-operated device having an on-board battery charger that is intended for use in hazardous atmospheres. The circuit complies with the IEC standard for intrinsically safe products.

Methods, apparatus, and articles of manufacture are disclosed for surge protection of a distributed control system component. An example apparatus includes an I/O module to be electrically coupled to a field device via a terminal block, the terminal block including a surge protector to reduce an input voltage to an operating voltage when the input voltage satisfies a first threshold, and a communication interface to generate a status message when the input voltage satisfies the threshold.

The present disclosure relates to a device for supplying energy to at least one intrinsically safe load in a potentially explosive area, the device including: a housing with an electrical input and with at least one electrical output, the housing is encapsulated in a pressure-proof manner, the electrical input encapsulated in a pressure-proof manner, and the at least one electrical output being intrinsically safe; an ignition protection module arranged in the housing and electrically connected to the electrical input and to the at least one electrical output, wherein the ignition protection module converts an electrical voltage present at the electrical input into an intrinsically safe electrical voltage and provides it at least one electrical output there, wherein the ignition protection module converts an electrical current present at the electrical input into an intrinsically safe electrical current and provides it at the at least one electrical output there.

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.

A circuit protection device is provided. The circuit protection device includes an active energy absorber that is coupled between two power lines in an electrical power distribution system and is configured to selectively conduct fault current responsive to overvoltage conditions. The active energy absorber includes an overvoltage protection module that includes two thyristors that are connected in anti-parallel with one another and a varistor that is connected with the overvoltage protection module as a series circuit. The series circuit including the varistor and the overvoltage protection module is connected between the power lines.