Abstract: Proposed is an earth leakage breaker having a built-in trip module type circuit breaker, which is installed at a line between a power supply and a load and has a trip module configured to cut the line off, the earth leakage breaker including: a CT installed on the line and configured to monitor an instantaneous current; and a control circuit unit comprising: an operation module configured to receive an instantaneous current sensed by the CT, to measure an instantaneous current value per unit time, and to calculate a slope of the instantaneous current per unit time; a determination module configured to determine a case as an overload state, the case having the slope exceeding an overcurrent determination value A, and to cause an overload state determination signal to be output; and an output module configured to output a trip module actuation signal according to the overload state determination signal of the determination module and to cut off the line, and accordingly, the earth leakage breaker causes the tri

Abstract: Disclosed is an airtight window, which can provide a space for enabling the window to be tilted during the fitting thereof into a window frame, and which cuts off the communication between an indoor area and an outdoor area so as to increase thermal insulation and prevent noise when installed. An upper frame of a window frame has a square C-shape with an open bottom, and has an installation end tightly contacting an installation part of a building and bent ends which extend downwardly from both ends of the installation end and which are bent inwardly so as to face each other. A movable frame of the window frame also has a square C-shape with an open bottom, and both ends thereof are formed into stopper ends so as to be disposed on and caught at the bent ends of the upper frame.