Abstract: According to an embodiment, when a transformer that is connected to a first power supply through a first breaker as well as to a second power supply through a second breaker is detected to be disconnected from the power supplies, a specific phase of the three phases of the first breaker is closed to suppress an excitation inrush current, based on calculated residual magnetic fluxes and a voltage of the first power supply, and thereafter, the remaining two phases are closed. Based on the calculated residual magnetic fluxes and a voltage of the second power supply, a specific phase of the three phases of the second breaker is closed to suppress an excitation inrush current, and thereafter, the remaining two phases are closed.

Abstract: According to an embodiment, when a transformer that is connected to a first power supply through a first breaker as well as to a second power supply through a second breaker is detected to be disconnected from the power supplies, a specific phase of the three phases of the first breaker is closed to suppress an excitation inrush current, based on calculated residual magnetic fluxes and a voltage of the first power supply, and thereafter, the remaining two phases are closed. Based on the calculated residual magnetic fluxes and a voltage of the second power supply, a specific phase of the three phases of the second breaker is closed to suppress an excitation inrush current, and thereafter, the remaining two phases are closed.

Abstract: A metal bond grind stone producing method in which electric power consumption is reduced is provided. In the metal bond grind stone producing method, a sintered metal bond grind stone is obtained by a sintering process of sintering a metal bond grind stone material that is a mixture of a metal binder powder and abrasive grains. In the sintering process, the metal bond grind stone material containing the metal binder powder is heated with microwaves to obtain the sintered metal bond grind stone. The sintering process may be a pressure sintering process of performing microwave heating while pressurizing the metal bond grind stone material.

Abstract: The present invention provides a microwave radiating device which treats a radiated material by microwave irradiation; and further provides a method of producing a sugar ingredient from a plant material. The microwave radiating device of the present invention is equipped with an irradiating means which has a microwave radiating source, and containers which accept radiated material inside. Further, the container of the device has supply means which provides radiated material to the container, and discharge means which discharges radiated material from the container, and a microwave receiving section which makes microwaves that irradiate from radiating means, penetrate into the container through the medium of dielectric material. Further, there is provided at least one layer that is composed of non-dielectric material, between the atmosphere of the inner side and the outer side of the container. Yet, irradiating means and the above container are connected in a removable mode.