Abstract: An object of the present invention is to provide a monitoring system, a monitoring device, and a construction machine each capable of improving the convenience for a user during monitoring while ensuring security related to the leakage of video data of a peripheral region. In a monitoring system 10 of the present invention, a monitoring device 30 reads information related to an access ID from a first authentication-related information display portion 208 arranged outside an operator's cab of a construction machine 20, using a second camera 300, and also reads information related to an access password from a second authentication-related information display portion 210 arranged in the operator's cab, using the second camera 300. The access ID may include a combination of the identification number of the construction machine 20 and a code representing the type of the construction machine 20.

Abstract: A plus-side main connection line (27) connects electrical equipment (21), (22) to a plus terminal (26A) of a battery (26). A plus-side isolating switch (28) is provided in the plus-side main connection line (27) to connect or disconnect the electrical equipment (21), (22) and or from the plus terminal (26A) of the battery (26). A plus-side auxiliary connection line (30) connects a urea SCR controller (25) to the plus terminal (26A) of the battery (26) in a position upstream of the plus-side isolating switch (28). A minus-side main connection line (32) connects a minus terminal (26B) of the battery (26) to ground. A minus-side isolating switch (33) is provided in the minus-side main connection line (32) to connect or disconnect the minus terminal (26B) of the battery (26) and or from ground.

Abstract: A work machine includes: a machine body; an actuator attached to the machine body; an operation device used to operate the actuator; an operation sensor that senses an operation of the operation device; a photographing device that photographs surroundings of the machine body; a video data recording device that records video data including video photographed by the photographing device; a controller that controls the video data recording device; and an object sensor that senses an object in the surroundings of the machine body. The controller determines whether or not a recording and retaining condition including a condition that an object is present in the surroundings of the machine body and a condition that the operation device is operated is satisfied on the basis of a result of sensing in the object sensor and a result of sensing in the operation sensor, and makes the video data recording device record and retain the video data when the recording and retaining condition is satisfied.

Abstract: A plus-side main connection line (27) connects electrical equipment (21), (22) to a plus terminal (26A) of a battery (26). A plus-side isolating switch (28) is provided in the plus-side main connection line (27) to connect or disconnect the electrical equipment (21), (22) and or from the plus terminal (26A) of the battery (26). A plus-side auxiliary connection line (30) connects a urea SCR controller (25) to the plus terminal (26A) of the battery (26) in a position upstream of the plus-side isolating switch (28). A minus-side main connection line (32) connects a minus terminal (26B) of the battery (26) to ground. A minus-side isolating switch (33) is provided in the minus-side main connection line (32) to connect or disconnect the minus terminal (26B) of the battery (26) and or from ground.

Abstract: A plus-side main connection line (17) connects electrical equipment (11), (12) to a plus terminal (16A) of a battery (16). A plus-side isolating switch (18) is provided in the plus-side main connection line (17) to connect or disconnect the electrical equipment (11), (12) and or from the plus terminal (16A) of the battery (16). A plus-side auxiliary connection line (20) connects a communication terminal (15) to the plus terminal (16A) of the battery (16) in a position upstream of the plus-side isolating switch (18). A minus-side main connection line (22) connects a minus terminal (16B) of the battery (16) to ground. A minus-side isolating switch (23) is provided in the minus-side main connection line (22) to connect or disconnect the minus terminal (16B) of the battery (16) and or from the ground.

Abstract: A reduction in measurement accuracy of a concentration sensor is minimized. An exhaust gas purifying device of a work machine includes a reduction catalyst that is placed in an exhaust flow passage of an exhaust gas of an engine and uses a reducing agent to reduce and purify nitrogen oxides in the exhaust gas, and a reducing agent injector to inject the reducing agent into the exhaust flow passage. The exhaust gas purifying device of a work machine includes: a storage unit that stores the reducing agent; a concentration sensor that has a sensing part placed within the storage unit to detect a concentration of the reducing agent; an air-bubble removal device that injects the reducing agent toward the sensing part; and a reducing agent pump that supplies the reducing agent in the storage unit to the air-bubble removal device.

Abstract: A reduction in measurement accuracy of a concentration sensor is minimized. An exhaust gas purifying device of a work machine includes a reduction catalyst that is placed in an exhaust flow passage of an exhaust gas of an engine and uses a reducing agent to reduce and purify nitrogen oxides in the exhaust gas, and a reducing agent injector to inject the reducing agent into the exhaust flow passage. The exhaust gas purifying device of a work machine includes: a storage unit that stores the reducing agent; a concentration sensor that has a sensing part placed within the storage unit to detect a concentration of the reducing agent; an air-bubble removal device that injects the reducing agent toward the sensing part; and a reducing agent pump that supplies the reducing agent in the storage unit to the air-bubble removal device.

Abstract: A plus-side main connection line (17) connects electrical equipment (11), (12) to a plus terminal (16A) of a battery (16). A plus-side isolating switch (18) is provided in the plus-side main connection line (17) to connect or disconnect the electrical equipment (11), (12) and or from the plus terminal (16A) of the battery (16). A plus-side auxiliary connection line (20) connects a communication terminal (15) to the plus terminal (16A) of the battery (16) in a position upstream of the plus-side isolating switch (18). A minus-side main connection line (22) connects a minus terminal (16B) of the battery (16) to ground. A minus-side isolating switch (23) is provided in the minus-side main connection line (22) to connect or disconnect the minus terminal (16B) of the battery (16) and or from the ground.