Патент USA US2405121код для вставки
Aug. 6, 1946. P. FEHR V 1 2,405,121 ’ COUNTING DEVICE FOR OVERVOLTAGE Filed Aug. 5, 1943 | 1 I INVENTOR fan! 7%!” ,_________J HTTORNEY . Patented ‘Aug. 6, 1946 2,405,121 UNITED STATES PATENT OFFICE 2,405,121 COUNTING DEVICE FOR OVERVOLTAGE Paul Fehr, Zug, Switzerland, assignor to Landis & Gyr A. G., a body corporate of Switzerland Application August 5, 1943, Serial No. 497,441 In Switzerland November 7, 1942 3 Claims. (Cl. 235-92) 1 2 There are several devices known in the art for counting voltage surges on long overhead lines Figs. 3 and 4 illustrate other forms of embodi ment. The invention is based on the utilization of the due to atmospheric in?uences or switchings. Such devices are based on magnetic, dynamic, thermal or chemical action of the current de ?ected by the protective devices in use. For instance, in a known form of embodiment, at a voltage-dependent resistance of the over thermal action of the de?ected current, whereby this—according to the diagrammatic representa tion in Fig. 1—is conveyed over a ?lament re sistance I, which is in the counting tank 2 ?lled with gas. The closure of the tank 2 forms a ?ex voltage conductor, a part of the voltage drop ible metallic diaphragm 3 being in connection caused by the de?ected (or discharged) current 10 with a counting train 4. Between the overhead is tapped and conveyed to the tWo coatings of a line 5 and the ground lies the protective conduc condenser to which an electro-magnetically 0p tor 6. The counting device is interposed be erated counting train is placed in parallel. After tween protective conductor 6 and grounded con having been charged, the condenser discharges ductor 1, whereby the de?ected current passes itself over the counting train and moves the 15 via the parallel connection of a voltage-depend same forward by one step. ent resistance 8 and a reactor (or choking coil) Another known type utilizes the thermal ac tion of the de?ected current by passing an end 9. The counting train 4 and the metallic dia phragm 3 are mechanically interconnected. less strip of paper longitudinally and transverse Fig. 2 represents a sectional view of a form of ly between a spark gap, whereby the strip gets 20 embodiment of the actuating device for the punctured at the incidence of a voltage surge. counting train. The numeral 3 designates a di In addition other arrangements have been aphragm consisting of a corrugated metallic tube known, which utilize electro-magnets in connec or pipe being slightly extensible in axial direc tion with spark gaps, explosion spark gaps, co tion. The tube piece with ?ange 10 serves as herers, &c. 25 connection between the corrugated metallic tube The purpose of all these known devices is to provide a check of the behaviour of the overvolt age conductor during the service and, for in stance, to ascertain how often the excess voltage conductor is affected during a, thunderstorm and thus protects the plant from damage; in which part of the overhead line the lightning conduc tors have acted and, if possible, to measure the approximate strength of the discharged current. Counting of voltage surges makes considerable demands on the counting devices, in view of the fact that the by-passed currents have a. very and the glass foot sealed onto it. The tank thus formed accommodates inside a ?lament resist ance I carried by supports 12 that are adapted as current leads. The hollow space is ?lled with an inert gas possessing a small speci?c heat value. A socket [3 with connecting plug l4 holds the whole arrangement together. 7 On the lid of the corrugated metallic tube 3 a pin I5 is provided which transfers the move VI ment of the diaphragm via the lever l6 by means of toothed segment I‘! and gear wheel l8 onto the counting train I 9. short duration, i. e. 10-8 to 10"2 sec. and have a In axially opposite position there is a compen sating diaphragm 20 with which the in?uences peak value of the order of 1000 amperes. The present invention for counting momentary of the ambient temperature on the diaphragm current impulses is characterized by the fact that a fraction of the de?ected currents ?owing through the conductance resistance is conveyed are nulli?ed. The action of the aforementioned device is as follows: If a discharge occurs in conductor 6, the de over a resistance which is in a tank ?lled with gas, whereby the gas expands under the in?uence 45 ?ected current produces at the voltage-depend of the ensuing heating and actuates the counting device through the medium of a ?exible dia ent resistance 8 a voltage drop. This voltage drop results in the transfer of a fraction of the de?ected current over the ?lament resistance I, phragm. The fundamental principle of the inventive idea may appear from a given form of embodi heating it. The heat thus produced is given off 50 to the gas in the counting tank, which gas ex ment according to the accompanying drawing, in which Fig. 1 showsa diagram of the arrangement. Fig. 2 is a cross-section of the gas-?lled count 65 ing tank and pands in consequence of its warming and drives the diaphragm 3 forwards, so that the pin [5 presses against the lever I6 which-by means of the toothed segment I'l—turns the gear wheel I8 and hence the counting train l9. 2,405,121 4 moves upwards, the disk is set free and performs an almost complete revolution, that is until an value is an inverse function of the current pass arresting stud 2'! engages the pin l5. By this ro ing through. Thus, as the current due to a surge tation the counting train has meanwhile been rises in intensity, the drop across resistance 8 driven through one ?gure only. may rise somewhat with the current and there When the gas in the counting tank 2 cools off, after remains at a predetermined maximum the pin i5 moves downwards thereby releasing value. Since the ?lament resistance is connected the arresting stud 21; the disk 25 continues to r0 directly across resistance 8, it is clear that the ’tate until the'arresting stud 25 again impinges on limit of maximum voltage drop across resistance & serves to protect the ?lament resistance against 10 pin l5 and the original position is again restored. The aforedescribed arrangement is adapted inv excessive currents being forced through it. Thus,- : > its employment for the counting and in combina resistance 8 has a tendency to smooth or ?atten tion witha suitable recording device for deter the voltage rise across it as current goes up and mining the approximate strength or“ the de?ected preserves ?lament resistance i from destruction Resistance 8 preferably is of the type whose in case of intense discharge. " ' 15 current, whereby the expansion of the diaphragm is utilized as a base value. The reactor 9 connected in paralle1 to the volt It will be evident that equivalents of the parts age-dependent resistance 8 has in turn for ‘its of the arrangement employed to accomplish the task to withhold from the counting tank the suc action of my said device might readily be devised ceeding current emanating from the line voltage, which current flows after the proper rush dis“ 20 which, however, would not depart from the scope of my invention. charge. This is achieved by selecting such a Having now particularly described and ascer value for the inductance of the reactor 9 that its tained the nature of my present invention and in impedance for the rush discharge is very high. what manner the same is to be performed, I de A comparatively small inductance is required for this purpose due to the steep current surge. Such 25 clare that what I claim is: i. A device for counting momentary power a small inductance, however, offers a low imped ance for the succeeding current after the initial steep wave front has passed. Such deviation of the succeeding current is necessary because its IZRt-Value may assume very high ?gures, and this would lead to the destruction of the filament re surges such as caused by lightning on a transmis sistance. wi . the gas oeing heated by said resistance, a line, said . 1 ce including a main current con ducting path, a resistance shunted across said main current conducting path, a gas-?lled ex oarsi‘cle cherub-er surrounding said resistance The device may likewise be so disposed that the pin :5 of the diaphragm directly controls a contact (Fig. 3) which operates a relay 22, thus actuating the counting train ‘3-. It is further conceivable that the counting train be driven by a clockwork 23 (see Fig. 4) and that the axial shifting of the pin !5 causes the clockwork to run counting device associated with said expansible chamber to be operated by each expansion cycle. 2. The system of claim 1 whereby said main current conducting path comprises an inductance. 3. The system of claim 1 wherein said main current conducting path has a resistance charac teristic such that the voltage drop across said down or arrests it by releasing the disk 25 for one revolution at a time. This, for instance, is brought about so, that the pin 55 in its rest position im pedes the disk 25 from rotating because it is in the path of an arresting pin 25. If the pin I5 path tends toward a maximum value irrespective 01‘ increase in current whereby said resistance shunted across said path is protected against excessive voltages. PAUL FEHR.