A switch assembly for a valve actuator can include a bracket, a rotatable switch rotatably coupled to the bracket at an adjustable angle, a fixed switch fixedly mounted to the bracket, an arm rotatably coupled to the bracket, and an adjustable switch trigger coupled to the arm. The rotatable switch can be tripped by the valve actuator and a trip point of the rotatable switch can be calibrated by setting the adjustable angle. The fixed switch can be tripped by the switch trigger on the arm and a trip point of the fixed switch can be set by adjusting the switch trigger relative to the arm. The assembly can include a calibration fixture for calibrating the switch assembly to the valve actuator independently of the valve actuator.

A switch assembly for a valve actuator can include a bracket, a rotatable switch rotatably coupled to the bracket at an adjustable angle, a fixed switch fixedly mounted to the bracket, an arm rotatably coupled to the bracket, and an adjustable switch trigger coupled to the arm. The rotatable switch can be tripped by the valve actuator and a trip point of the rotatable switch can be calibrated by setting the adjustable angle. The fixed switch can be tripped by the switch trigger on the arm and a trip point of the fixed switch can be set by adjusting the switch trigger relative to the arm. The assembly can include a calibration fixture for calibrating the switch assembly to the valve actuator independently of the valve actuator.

A system for short-circuiting or grounding low-voltage and/or medium-voltage installations. The system includes at least one fault detection unit for detecting an arc and at least one signal-processing unit for processing signals from the at least one fault detection unit. The signal-processing unit is or can be connected to the fault detection unit for signal transmission. The system further includes at least one control unit which is or can be connected to the signal-processing unit for signal transmission, an electrical energy storage device in or on the control unit, and at least one fast-switching switching element having a mechanical energy store.

A switch assembly for a valve actuator can include a bracket, a rotatable switch rotatably coupled to the bracket at an adjustable angle, a fixed switch fixedly mounted to the bracket, an arm rotatably coupled to the bracket, and an adjustable switch trigger coupled to the arm. The rotatable switch can be tripped by the valve actuator and a trip point of the rotatable switch can be calibrated by setting the adjustable angle. The fixed switch can be tripped by the switch trigger on the arm and a trip point of the fixed switch can be set by adjusting the switch trigger relative to the arm. The assembly can include a calibration fixture for calibrating the switch assembly to the valve actuator independently of the valve actuator.

An anomaly diagnosis device diagnoses anomaly of an oil-hydraulic operating mechanism that controls opening and closing of a circuit breaker. The anomaly diagnosis device includes: a first counter, which is a counter that counts the number of times of a pressure-increasing operation started upon a decrease in a hydraulic pressure maintained in the oil-hydraulic operating mechanism to a first reference pressure, and stopped upon an increase in the hydraulic pressure to a second reference pressure; a timer that measures an operation interval that is a time period from when a pressure-increasing operation is stopped until a next pressure-increasing operation is started; and an anomaly determiner that corrects, based on the operation interval, the number of pressure-increasing operations obtained based on a result of counting by the counter, and determines presence or absence of an anomaly in the oil-hydraulic operating mechanism using the corrected data of the number of pressure-increasing operations.

An anomaly diagnosis device diagnoses anomaly of an oil-hydraulic operating mechanism that controls opening and closing of a circuit breaker. The anomaly diagnosis device includes: a first counter, which is a counter that counts the number of times of a pressure-increasing operation started upon a decrease in a hydraulic pressure maintained in the oil-hydraulic operating mechanism to a first reference pressure, and stopped upon an increase in the hydraulic pressure to a second reference pressure; a timer that measures an operation interval that is a time period from when a pressure-increasing operation is stopped until a next pressure-increasing operation is started; and an anomaly determiner that corrects, based on the operation interval, the number of pressure-increasing operations obtained based on a result of counting by the counter, and determines presence or absence of an anomaly in the oil-hydraulic operating mechanism using the corrected data of the number of pressure-increasing operations.