| 摘要 |
1,221,578. Current measurement. KNAPSACK A.G. Sept. 18, 1968 [Sept. 22, 1967], No. 44362/68. Addition to 1,144, 282. Heading G1U. [Also in Division G3] In a system for determining the currents passing through the individual electrodes of an electrolytic cell, so as to determine whether these electrodes need to be adjusted, voltages across resistors 1, 2, 3 in series with respective electrodes, are applied cyclically, by operating a selective switching mechanism incorporating switches 8, 9, 10 in series with the output leads from the resistors, under the control of a timed impulse generator 7, to a compensation system in which the voltage from a selected resistor is compared with a reference voltage corresponding with the mean electrode current. The difference voltage represents the deviation in the current in the selected resistance from the mean electrode current and is passed to a limit monitor. This monitor generates an output if the voltage difference is outside a predetermined tolerance range, the output being on one lead if the difference is positive and on another if it is negative. The compensation system has an input potentiometer 15, which is adjusted in accordance with the average current flowing through each electrode of the whole cell, so that if the average current is flowing in the particular electrode under test, balance between the test and reference voltages will be achieved and no fault indication given. The total cell current is measured as a voltage across a resistor 21 through which it flows, by a potentiometric method in which the wiper of a potentiometer 25 is automatically adjusted to represent the current, the wiper of this potentiometer being mechanically coupled to that of the potentiometer 15. Each detector resistor in the individual electrode leads has a potentiometer 4, 5, 6 &c. in parallel with it, this being adjusted so that when the mean current flows through the resistor, the correct output voltage is obtained (corrected for resistance variation &c. The indicator system incorporates a pair of differently coloured lamps for each electrode, one being illuminated when the current is below the permissible tolerance range, the other when it is above. The signals from the limit monitormay in addition be applied to a computer which effects automatic adjustment of the electrodes. Furthermore the system may be used to test cyclically the potential drop across transistion resistances in the electrode leads, due to soldered on mechanical joints &c. the values determined being used to achieve accurate correction of the electrode currents. |
