Power interface control device of a vehicle propulsion battery potential ports to carry out differential potential measurements, a current sensor to measure a current supplied by the propulsion battery and a closed container made of insulating material to which said ports and said sensor are associated, wherein said container comprises connection means to allow a mechanical coupling between the container and said electrical conductor.

A safety switch device configured to perform at least one of connecting a load to a power supply and disconnecting the load from the power supply is provided. The safety switch device comprises a first set of two serially connected controllable switching elements; a safety circuit to verify a switching state of the first set of two switching elements, wherein each switching element of the first set of two switching elements is configured as a toggle; a control circuit configured to provide a test signal to the safety circuit; and decoupling means configured to galvanically decouple the load circuit from the control circuit. The decoupling means comprise a transformer, and the control circuit comprises a transformer driver configured to provide the test signal to the safety circuit via the transformer.

Safety switching device for the fail-safe disconnection of an external consumer having an internal consumer and switching elements for connecting in parallel the internal consumer with the external consumer. Read-back taps are arranged between the switching elements, a first and second pole of the external consumer, and the internal consumer. A signal processing unit comprises a testing device and a memory, in which a first error pattern set is stored. The testing device is coupled to the read-back taps and executes a switching test having a minimum of three temporally-separated test intervals. In each test interval, the testing device receives a read-back signal from each read-back tap in order to generate a first test pattern. To identify a fault, the testing device matches the first test pattern with the first error pattern set.

The present invention realizes a relay device that can prevent malfunction due to occurrence of reverse flow of current in any of paths. A control unit that is provided in a relay device functions as a switching control unit, keeps an ON state of a first relay unit and a second relay unit if both of currents flowing through a first conduction path and a second conduction path flow in a normal direction (direction toward a load, and if the current flows in the reverse direction in one of the paths, switches one relay unit that is provided in a reverse flow path in which the current flows in a reverse direction to an OFF state.

A switch assembly including a switch and a drive system for the switch. The drive system includes a motor for driving the switch, a control device with a power section for supplying power to the motor, a controller for initiating a switching operation of the switch by control of the power section, and a protection circuit. The protection circuit is configured to detect a first error signal via a state contact of the controller in the event of a malfunction of the controller, detect a second error signal via a state contact of the power section in the event of a malfunction of the power section, and initiate a safety measure depending on the first and the second error signal. The control device is configured to activate the protection circuit prior to the switching operation being initiated and to deactivate it following successful execution of the switching operation.

A miniature and inexpensive relay device is provided. A relay device, i.e., a relay unit, includes a breakdown detection unit that does not detect breakdown of an operation of a first switching element and detect breakdown of an operation of a second switching element. When a switching control unit switches an external load circuit from non-conductivity to conductivity, the switching control unit switches the second switching element from non-conductivity to conductivity after switching the first switching element from non-conductivity to conductivity. When the switching control unit switches the load circuit from conductivity to non-conductivity, the switching control unit switches the first switching element from conductivity to non-conductivity after switching the second switching element from conductivity to non-conductivity.

To enable a safe monitoring with a small cabling effort of a modular safety relay circuit, a modular safety relay circuit for the safe control of at least one machine is provided comprising a safety relay unit that has at least one forcibly guided relay for the safe switching on and off of the machine and that generates output signals in dependence on input signals, wherein the input signals are provided by at least one connected signal transmitter and the output signals are communicated to the at least one machine; and at least one expansion relay unit for providing additional output connectors so that additional machines can be connected; wherein the expansion relay unit has at least one respective forcibly guided relay for the safe switching on and off of the machine and is monitored by means of a monitoring relay.

Embodiments of the present disclosure relate to a control circuit for a contactor and a control method thereof. The control circuit comprises: a pulse converter configured to convert a turn-on control signal into a continuous pulse signal; a first controller configured to generate a first breaking control signal at a first time in response to detection of the disappearance of the continuous pulse signal received from the pulse converter; a second controller configured to generate a second breaking control signal at a second time in response to detection of the disappearance of the continuous pulse signal received from the pulse converter, wherein the first time is earlier than the second time; and a coil driver configured to turn off a current of the excitation coil according to the received first breaking control signal, and if the current is not turned off according to the first breaking control signal, to further turn off the current of the excitation coil according to the second breaking control signal, thereby realizing the breaking of the main contact.

A relay control circuit includes a relay module, a drive module, and a control module. The relay module comprises a plurality of relays and an auxiliary diagnostic unit electrically coupled to the relays. The drive module comprises a drive chip electrically coupled to the relays. The control module comprises a control unit electrically coupled to the drive chip and the auxiliary diagnostic unit. Each of the drive chip and the auxiliary diagnostic unit detects an operating state of each relay, and outputs the operating state of each relay to the control unit. When the operating state of each relay detected by the drive chip or the operating state of each relay detected by the auxiliary diagnostic unit indicates any relay fails, the control unit controls the drive chip to stop operating, and each relay is turned off.

Disclosed in the present invention are a method of electricity leakage detection and prevention of electrical equipment's outer surface and system thereof. The method and system are used for detecting and preventing electricity leakage of the electrical equipment's outer surface caused by defective insulation and power supply connection faults. Without in touch with the electrical equipment's outer surface, the electricity leakage of the outer surface can be detected and the connection between the electrical equipment and the power supply can be cut and an alarm is made by means of the current channel (2) formed between the electrical equipment neutral line (N) and the electrical equipment's outer surface (G) and the monitoring of the current value. A power supply channel (5) is set up to make sure that the electrical equipment can be normally operated via the system even in the condition of the power supply connection faults. According to the method and system, the electricity leakage of the outer surface can be correctly detected and the alarm can be made or the connection between the electrical equipment and the power supply can be cut even if the electrical equipment's outer surface is not grounded. With the advantage of simple construction and low cost, the system can be widely used.