Systems and methods for automatically verifying that power relays have been disconnected include relays arranged between two power sources. Test nodes are positioned between the relays on each line, and feed into a detection circuit. Voltage drop resistors, voltage drop diodes, an optocoupler, and additional resistors and capacitors are used to provide voltage isolation for the detection circuit. Relays are methodically opened and closed to check the individual functioning of each relay, and a digital signal generated from the detection circuit. The design of the system with detection circuit isolation provides a safer and lower cost system for verifying that relays are operating correctly, with less costly components than traditional systems.

An output module comprising an output circuit and a control unit and an industrial control device including the output module are provided. The output circuit includes switches connected in parallel with each other, a specific power supply provided for each switch, and a current detection unit that is provided for each switch and, in response to an application of a function diagnosis voltage from the specific power supply, outputs a current signal indicating whether an applied current has flowed through the switch, to the control unit. The control unit determines a diagnosis target switch, and based on the current signal from the current detection unit, conducts the function diagnosis including determination as to whether opening control is normally active for at least the diagnosis target switch, while leaving at least any one switch other than the diagnosis target switch in a closed state.

Systems and methods for contact erosion mitigation are provided. To perform contact erosion mitigation, an order of opening/closing poles and/or contact relays of particular poles is altered, resulting in a sharing of potential arcing conditions amongst the poles/contact relays of these poles.

A converter includes two switching stages coupled in series between positive and negative input terminals. A control circuit is configured for driving the switching stages based on an output voltage of the converter. A first switching stage includes two switches coupled in series between a positive input terminal and a first node. A capacitor and an inductor are coupled in series between the two switches and a positive output terminal. A third switch is coupled between a node between the capacitor and the inductor and the negative input terminal. A second capacitor is coupled between the first node and the negative input terminal. A second switching stage includes a second node coupled to the first node. Two additional electronic switches are coupled in series between the second node and the negative input terminal. A second inductor is coupled between the two additional switches and the positive output terminal.

The Robust Safe Switch and Control Device is an “Internet of Things” end effecter that provides a minimally dissipating, robust switch tightly integrated with circuit, life and property automated safety features. The device enables extended sensing and monitoring capabilities that enable the effective management of the “Internet of Things.”

Disclosed is a method and system for detecting faults of a battery heating system and relays. In particular, a method for detecting welding of each relay such as a main relay, a precharge relay or a heater relay and a method for detecting a fault of a battery heating system such as a short circuit, disconnection or damage of each heater are provided by sensing a voltage. In the methods, the on/off state of the heater relay and the high voltage relays is controlled through a predetermined process to detect a fault of the heater relay or the high voltage relay, and welding of the heater relay or the high voltage relay is then detected from a voltage for fault detection which is sensed through a voltage sensing circuit unit for fault detection.

An apparatus for detecting a state of a relay includes a voltage outputter configured to output a voltage having a different voltage value for each state of each of a plurality of relays configured to switch a connection between a battery and a load, and a controller configured to determine whether each of the plurality of relays is welded based on the voltage output from the voltage outputter.

A contactor failure determining method in includes outputting a control signal for switching a positive-side contactor provided between a positive electrode of a multi-cell battery and a positive electrode of a load to which the multi-cell battery supplies electric power to an open state from a state in which a control signal for controlling the positive-side contactor and a negative-side contactor provided between a negative electrode of the multi-cell battery and a negative electrode of the load to a closed state and a precharge contactor provided between the multi-cell battery and the load to an open state is output, and as a first fixing determining step, determining a presence of fixing of the precharge contactor based on a degree of voltage drop of a voltage applied to the load after the control signal for switching the positive-side contactor to the open state is output.

The relay safety system provided by the present invention includes a relay, an emergency stop device, a trigger detection circuit, a sticking detection circuit, and a power-off circuit. The emergency stop device is used to generate an emergency stop signal. The trigger detection circuit connects the relay and the emergency stop device, and is used to convert the emergency stop signal into a trigger signal. The sticking detection circuit is connected to the trigger detection circuit and the relay, and is used to detect the sticking signal generated by the relay, and generate a power-off signal according to the trigger signal and the sticking signal. The power-off circuit is connected to the emergency stop device, the relay and the sticking detection circuit, and receives the power-off signal, and disconnects the power of the relay according to the power-off signal.

Systems and methods for automatically verifying that power relays have been disconnected include relays arranged between two power sources. Test nodes are positioned between the relays on each line, and feed into a detection circuit. Voltage drop resistors, voltage drop diodes, an optocoupler, and additional resistors and capacitors are used to provide voltage isolation for the detection circuit. Relays are methodically opened and closed to check the individual functioning of each relay, and a digital signal generated from the detection circuit. The design of the system with detection circuit isolation provides a safer and lower cost system for verifying that relays are operating correctly, with less costly components than traditional systems.