DE624249C - Electrical circuit for displaying the sum of measured quantities - Google Patents

Description

GERMAN EMPIRE

ISSUED ON JANUARY 16, 1936

REICH PATENT OFFICE

PATENT LETTERING

CLASS 42 d GROUP

Allgemeine Elektricitäts-Gesellschaft in Berlin *) Electrical circuit for displaying the sum of measured quantities

Patented in the German Empire on April 4, 1933

The invention relates to electrical circuits

for displaying the sum of measured variables using resistors connected in parallel, the tapping of which is changed according to the measured variables.

Up to now it was of the opinion that in this case only the middle part of the transmitter resistances could be used. For this reason it has been proposed in a known circuit to provide a larger series resistor on both sides of the transmitter resistor, so that the percentage change in the two parts of the transmitter resistance is only very small. Such a circuit is shown in Fig. Ι. The power source is designated by 1. 2 and 3, the two windings of serving as a receiving instrument Quotientenmeßinstrumentes. On the encoder resistors 4 _0, 4 _δ, 4 "grind the displaceable taps y _a, y _6, 7 _C.

5a. 5z »5c or. 6 ₀ , 6 ₆ , 6 "are the larger fixed resistors connected in series with the variable resistors, whose dimensions can be carried out in such a way that the various measuring ranges of the transmitter instruments are taken into account. So there are two balancing resistors required for each encoder, the balancing and placement in the small housing of the usual encoder device is associated with considerable difficulties. This type of summation is particularly cumbersome for all those summation arrangements in which the sum measurement is to be set up for switchable measuring ranges of the sensors.

According to the invention, the arrangement is made so that when connected directly in parallel Resistors, the series resistors are connected in front of the tapping points and lead to a common branch point.

Circuits according to the invention are shown in Figs. An embodiment of the invention for the summation of measured variables using transmitter resistances and a quotient instrument for display is illustrated in FIG. Parts 1, 2, 3, 7a>7b> 7c correspond to the parts of the same name in Fig. I. The new finding consists in the fact that only one balancing resistor 8 _O , 8 ₆ , 8 _C is required for each transmitter in order to achieve a correct summation, possibly taking into account the different measuring ranges of the transmitters. This is done in such a way that the transmitter resistors 7 are designed differently or that the series resistors 8 are made different from one another.

When adding up the deflections of similar transmitters, the display of the sum instrument is correct if the resistances 7 just as the resistors 8 are equal to one another. There were manufacturing difficulties there may be deviations in the implementation of exactly the same type of encoder resistance of the resistors 7 by

*) The patent seeker stated as the inventor:

Dr.-Ing. Herbert Dattmannn in Berlin-Karlshorst.

Speaking dimensioning of the series resistors 8 are compensated. Do you want that Series resistors 8 among each other. do the same, you can make a match in the Make way that the transmitter resistors 7, as Fig. 3a and 3b show, preferably in several equal parts are divided and resistors 9 ', 9 "etc. are parallel to these parts be switched. Depending on the intended

The size of the change in the resistance characteristic is the number of steps in the parallel resistance 9 to choose so that the overall arrangement practically like an evenly subdivided Resistance works.

The extension of the circuit according to Fig. 2 for the case that the transmitter instruments several have optionally switchable measuring ranges, is shown in Fig. 4. Have the resistors 8 several taps to be switched on depending on the existing measuring ranges of the encoder are. If you want to ensure that the full scale length of the receiving instrument is used in all measuring ranges, im general 'to provide one or more additional balancing resistors 9, depending on are to be set for the existing measuring ranges.

Claims (5)

Patent claims: i. Electrical circuit for displaying the sum of measured quantities in a quotient measuring device using sensor resistors connected in parallel with tapping and series resistors influenced by the measured variable, characterized in that the series resistors are in front of the tapping points are switched and lead to a common branch point. 2. Circuit according to claim 1, characterized in that the series resistors so are chosen that with mutually different measuring ranges of the transmitter instruments the individual transmitters act on the receiver according to their measuring range. 3. A circuit according to claim 1, characterized in that for balancing the Measurement arrangement divided the encoder resistances one or more times and parallel to the Partial resistors fixed balancing resistors are connected. 4. A circuit according to claim 1 and 2, characterized in that in the case of several switchable measuring ranges of the transmitter instruments the series resistances of these measuring ranges have appropriate, optionally switchable taps. 5. Device according to claim 4, characterized in that one or more additional Balancing resistors are provided, which are used when the measuring ranges are changed Influencing the receiver deflection can be switched. 1 sheet of drawings