Abstract: An uninterrupted power supply unit is provided with a straightforward switch connected between a power source and a load to supply or interrupt a power to a system. The combination of the outputs from two kinds of single phase inverters enables compensating for a variation in the system voltage in the normal condition and to supply a predetermined voltage to the load after decreasing in the system voltage and opening of a straight forward switch.

Abstract: An uninterrupted power supply unit is provided with a straightforward switch connected between a power source and a load to supply or interrupt a power to a system. The combination of the outputs from two kinds of single phase inverters enables compensating for a variation in the system voltage in the normal condition and to supply a predetermined voltage to the load after decreasing in the system voltage and opening of a straight forward switch.

Abstract: An uninterrupted power supply unit is provided with a straightforward switch connected between a power source and a load to supply or interrupt a power to a system. The combination of the outputs from two kinds of single phase inverters enables compensating for a variation in the system voltage in the normal condition and to supply a predetermined voltage to the load after decreasing in the system voltage and opening of a straight forward switch.

Abstract: An uninterrupted power supply unit is provided with a straightforward switch connected between a power source and a load to supply or interrupt a power to a system. The combination of the outputs from two kinds of single phase inverters enables compensating for a variation in the system voltage in the normal condition and to supply a predetermined voltage to the load after decreasing in the system voltage and opening of a straight forward switch.

Abstract: An instantaneous voltage dip detection device is provided with: all-pass filter (2) for phase shifting a supply voltage waveform (11) by 90°; a comparator 7 that outputs a signal when the supply voltage waveform (11) is smaller than a threshold (12) in regions of ?/4 to 3?/4, 5?/4 to 7?/4; a comparator (8) that outputs a signal when a phase shift voltage waveform (13) is smaller than a threshold (14) in regions of 0 to ?/4, 3?/4 to 5?/4, 7?/4 to 2?; an OR circuit (9) to which signals from the comparators (7), (8) are inputted; and a signal generator (10) for generating a voltage dip detection signal in response to an output from the OR circuit (9).

Abstract: An instantaneous voltage dip detection device is provided with: all-pass filter (2) for phase shifting a supply voltage waveform (11) by 90°; a comparator 7 that outputs a signal when the supply voltage waveform (11) is smaller than a threshold (12) in regions of ?/4 to 3?/4, 5?/4 to 7?/4; a comparator (8) that outputs a signal when a phase shift voltage waveform (13) is smaller than a threshold (14) in regions of 0 to ?/4, 3?/4 to 5?/4, 7?/4 to 2?; an OR circuit (9) to which signals from the comparators (7), (8) are inputted; and a signal generator (10) for generating a voltage dip detection signal in response to an output from the OR circuit (9).

Abstract: A laminate containing a polyolefin resin composition containing ethylene-&agr;-olefin copolymer having: (A) a density d of 0.86 to 0.96 g/cm3; (B) a melt flow rate MFR of 0.01 to 200 g/10 min; (C) a molecular weight distribution Mw/Mn of 1.5 to 4.5; (D) a composition distribution parameter Cb of 1.08 to 2.00; and (E) an orthodichlorobenzene-soluble content X (wt %), at 25° C. a density of d (g/cm3) and a melt flow rate MFR (g/10 min) satisfying that: (i) when the density (d) and the melt flow rate MFR satisfy relationship (I): d−0.008×log MFR≧0.93  (I)  the orthodichlorobenzene-soluble content X satisfies relationship (II): X<2.0  (II) (ii) when the density d and the melt flow rate MFR satisfy relationship (III): d−0.008×log MFR<0.93  (II)  the orthodichlorobenzene-soluble content X satisfies relationship (IV): X<9.8×103×(0.9300−d+0.008×log MFR)2+2.

Abstract: A polyolefin resin composition containing an ethylene-.alpha.-olefin copolymer having: (A) a density d of 0.86 to 0.96 g/cm.sup.3 ; (B) a melt flow rate MFR of 0.01 to 200 g/10 min; (C) a molecular weight distribution Mw/Mn of 1.5 to 4.5; (D) a composition distribution parameter Cb of 1.08 to 2.00; and (E) an orthodichlorobenzene-soluble content X (wt %), at 25.degree. C. a density of d (g/cm.sup.3) and a melt flow rate MFR (wt %) satisfying that: (i) when the density (d) and the melt flow rate MFR satisfy relationship (I):d-0.008.times.logMFR.gtoreq.0.93 (I)the orthodichlorobenzene-soluble content X satisfies relationship (II):X<2.0 (II)(ii) when the density d and the melt flow rate MFR satisfy relationship (III):d-0.008.times.logMFR<0.93 (III)the orthodichlorobenzene-soluble content X satisfies relationship (IV):X<9.8.times.10.sup.3 .times.(0.9300-d+0.008.times.logMFR).sup.2 +2.

Abstract: An ethylene-.alpha.-olefin copolymer having: (A) a density d of 0.86 to 0.96 g/cm.sup.3 ; (B) a melt flow rate MFR of 0.01 to 200 g/10 min; (C) a molecular weight distribution Mw/Mn of 1.5 to 4.5; (D) a composition distribution parameter Cb of 1.08 to 2.00; and (E) an orthodichlorobenzene-soluble content X (wt %), at 25.degree. C. a density of d (g/cm.sup.3) and a melt flow rate MFR (g/10 min) satisfying that: (i) when the density (d) and the melt flow rate MFR satisfy relationship (I):d-0.008.times.logMFR.gtoreq.0.93 (I)the orthodichlorobenzene-soluble content X satisfies relationship (II):X<2.0 (II)(ii) when the density d and the melt flow rate MFR satisfy relationship (III):d-0.008.times.logMFR<0.93 (III)the orthodichlorobenzene-soluble content X satisfies relationship (IV):X<9.8.times.10.sup.3 .times.(0.9300-d+0.008.times.logMFR).sup.2 +2.

Abstract: A trip control device for monitoring and tripping a circuit breaker includes a first voltage detector 11 and a second voltage detector 12 for detecting the first and second reference voltages corresponding to the maximum allowable voltage level and the operation resumable voltage level, wherein the second reference voltage is set higher than the first reference voltage. The output of the second voltage detector 12 at logical 1 reduces the output of the first voltage detector 11 to the logical 0 through a transistor 14 and a capacitor 15 with a predetermined delay. The logical sum T of the outputs of the first voltage detector 11and the second voltage detector 12, output from the OR gate 13, turns off the drive circuit 3 when at logical 0, to de-energize the electromagnetic coil 4 and render the associated circuit breaker incapable of being made.

Abstract: An overcurrent detector circuit for a circuit-breaker includes two systems for overcurrent detection. In the first system, the level of the current detected by the current detectors 41 is converted to a digital signal by the A/D converter 91 at each 500 microseconds. The maximum value detector 92 selects the maximum value among these digital signals over each period of 12.5 milliseconds. When the maximum value is greater than a pick-up level, the square thereof is accumulated in the counter 95. In the second system, the calculation circuit 96 squares the digital signals of the A/D converter 91, and switches its outputs in order to the counters 97-1 through 97-5 at a period of 25 milliseconds. Thus, the four counters other than that currently coupled to the calculation circuit 96 hold together the squares of the digital signals accumulated over 100 milliseconds.

Abstract: When a voltage (V) of a D.C. power source having an internal resistance (5a) exceeds an "exciting voltage" (FIG. 2), transistors (21, 28 and 33) turn ON, and a transistor (30) turns OFF, and then a tripping winding 16 is excited to close a circuit breaker; on the other hand when the voltage (V) is lowered under a "tripping voltage", the transistor (33) turns OFF and the transistor (30) turns ON, and thereby a load resistor (31) which is less than a resistance 34 of the tripping winding 16 is connected to the D.C. power source; consequently, the voltage V is further lowered by the internal resistance (5a), and a voltage difference is produced between the exciting voltage and the tripping voltage, thus making a "hysteresis characteristic" between the exciting voltage and the tripping voltage.

Abstract: A circuit breaker has a phase selecting circuit for selecting one phase among plural phases, in which the largest current flows. After selecting the largest phase, the judgement whether an accidental overcurrent flows or not in executed by using only output signals from the selected largest phase.

Abstract: A circuit breaker having three level discriminating circuits and time-current operating circuits, respectively corresponding to an instantaneous releasing, a short time characteristic releasing and a long time characteristic releasing of disconnectable contacts.

Abstract: A power source device for a circuit breaker responsive to a current output of a current detection circuit having a capacitor chargeable to provide a voltage output and a switching circuit for switching between charging and discharging states of the capacitor. A dummy burden is connected to the switching circuit and set at a substantially equal burden formed by a load and a constant voltage generating circuit to eliminate fluctuations in the charging and discharging states of the capacitor. As a result, accuracy in the detected current output is substantially improved without the use of a high-capacitance and high-withstand-voltage capacity.