Abstract: The present disclosure relates to a grounding monitoring device, method, system and computer readable storage medium, which relates to the field of coal mine safety. The device includes: a measurement power source for supplying power to the grounding monitoring device; a resistance measurement device connected between the measurement power source and a grounding electrode, the resistance measurement device, the measurement power source and the grounding electrode forming a current detection circuit via the ground, wherein a resistance of a grounding resistor is determined according to a current flowing through the grounding electrode in the current detection circuit to determine a monitoring result.

Abstract: The present disclosure relates to a grounding monitoring device, method, system and computer readable storage medium, which relates to the field of coal mine safety. The device includes: a measurement power source for supplying power to the grounding monitoring device; a resistance measurement device connected between the measurement power source and a grounding electrode, the resistance measurement device, the measurement power source and the grounding electrode forming a current detection circuit via the ground, wherein a resistance of a grounding resistor is determined according to a current flowing through the grounding electrode in the current detection circuit to determine a monitoring result.

Abstract: A dual-prevention lock device for locking a screw and a method for locking a screw. The dual-prevention lock device comprises: a lower lock body (6); an upper lock body (1) mounted on the lower lock body (6), a receiving space for receiving a screw (3) to be locked being formed between the upper lock body (1) and the lower lock body (6); and a lock core (11) mounted on the lower lock body (6). A lower clamping part extending into the receiving space is disposed on the lower lock body (6), and an upper clamping part extending into the receiving space is disposed on the upper lock body (1). Under the action of a key, the lower clamping part is pushed by the lock core (11), so that the screw (3) to be locked is locked in the receiving space by the lower clamping part and the upper clamping part. With the upper and lower clamping parts for locking the screw, the dual-prevention lock device has a reliable performance and a simple structural design.

Abstract: Provided are a method and apparatus for remote coal mine leakage test. The remote leakage test method comprising: installing and connecting a leakage test device (3) at the a control switch (2) located at the most distal end of a coal mine power line (5); a leakage detection and protection device (1) connecting the leakage test device (3) via the coal mine power line (5) and providing it with a detection circuit for detecting whether remote leakage has occurred; generating a grounding current flowing through the coal mine power line (5) by controlling the grounding of the leakage test device (3); the leakage detection and protection device (1) detecting the grounding current, and enabling a leakage protection relay (KA) to operate, so as to cut off the coal mine power line (5); and detecting the coal mine power line (5) or manually observing an indication lamp (HL), so as to determine whether the remote leakage test is successful.

Abstract: Provided are a method and apparatus for remote coal mine leakage test. The remote leakage test method comprising: installing and connecting a leakage test device (3) at the a control switch (2) located at the most distal end of a coal mine power line (5); a leakage detection and protection device (1) connecting the leakage test device (3) via the coal mine power line (5) and providing it with a detection circuit for detecting whether remote leakage has occurred; generating a grounding current flowing through the coal mine power line (5) by controlling the grounding of the leakage test device (3); the leakage detection and protection device (1) detecting the grounding current, and enabling a leakage protection relay (KA) to operate, so as to cut off the coal mine power line (5); and detecting the coal mine power line (5) or manually observing an indication lamp (HL), so as to determine whether the remote leakage test is successful.

Abstract: A pre-cover-opening power-off method, comprising the steps of: (a) fixing a bolt casing to a bolt; (b) connecting a motion sensor to a safety protecting and monitoring unit in a wired or wireless manner; and (c) activating the motion sensor to send out a command to permit power delivery for an electrical equipment to operate, and when the bolt casing is taken off, the motion sensor is activated to send out a command to cut off a power supply for the electrical equipment or give out an alarm.

Abstract: A pre-cover-opening power-off method, comprising the steps of: (a) fixing a bolt casing to a bolt; (b) connecting a motion sensor to a safety protecting and monitoring unit in a wired or wireless manner; and (c) activating the motion sensor to send out a command to permit power delivery for an electrical equipment to operate, and when the bolt casing is taken off, the motion sensor is activated to send out a command to cut off a power supply for the electrical equipment or give out an alarm.

Abstract: A dual-prevention lock device for locking a screw and a method for locking a screw. The dual-prevention lock device comprises: a lower lock body (6); an upper lock body (1) mounted on the lower lock body (6), an receiving space for receiving a screw (3) to be locked being formed between the upper lock body (1) and the lower lock body (6); and a lock core (11) mounted on the lower lock body (6). A lower clamping part extending into the receiving space is disposed on the lower lock body (6), and an upper clamping part extending into the receiving space is disposed on the upper lock body (1). Under the action of a key, the lower clamping part is pushed by the lock core (11), so that the screw (3) to be locked is locked in the receiving space by the lower clamping part and the upper clamping part. With the upper and lower clamping parts for locking the screw, the dual-prevention lock device has a reliable performance and a simple structural design.

Abstract: A pre-cover-opening power-off method, comprising the steps of: (a) fixing a bolt casing to a bolt; (b) connecting a motion sensor to a safety protecting and monitoring unit in a wired or wireless manner; and (c) activating the motion sensor to send out a command to permit power delivery for an electrical equipment to operate, and when the bolt casing is taken off, the motion sensor is activated to send out a command to cut off a power supply for the electrical equipment or give out an alarm.

Abstract: A pre-cover-opening power-off method, comprising the steps of: (a) fixing a bolt casing to a bolt; (b) connecting a motion sensor to a safety protecting and monitoring unit in a wired or wireless manner; and (c) activating the motion sensor to send out a command to permit power delivery for an electrical equipment to operate, and when the bolt casing is taken off, the motion sensor is activated to send out a command to cut off a power supply for the electrical equipment or give out an alarm.