PURPOSE: To detect break of rope surely without arranging operators on the site of a coke oven, to prevent damage of devices, and to make the coke oven efficient, by detecting the primary current of a motor to drive the rope of levler bar, inputting it to a current relay.
CONSTITUTION: The MC7 for shorting the secondary resistance and the resistance 2 are alternately connected in series at the secondary side of the motor 1 to drive a leveler. The MC8 for advancing the leveler and the MC9 for backing it are connected at the primary side of the motor 1, and the current transformer 3 in which the rectifier 4 and the current relay 5 are connected in series is inserted at the side of electric source. When the motor 1 is started, the primary current increases and reaches to the peak a, and changes to the load current b to operate the relay 5. When a rope to drive a leveler is broken, no load is applied, and the primary current is reduced from point c to point d, in the range B, the relay 5 is not operated, so that break of rope is detected.
HASEGAWA JIYUN
MATSUURA KATSUHIRO
HIGAKI TAKAHIRO
FUJITA KENJI
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