SU738148A1 - Voltage measuring device - Google Patents

Description

(54) DEVICE FOR MEASURING STRESS

one

The invention relates to automation and computing and can be used in devices for converting continuous information to discrete, for example, in digital voltmeters.

A voltage measuring device made in the form of a voltage converter is a digital code containing a recording signal generator, a transformer with one winding and two output windings, a magnetotransistor pulse generator and gates 1.

The disadvantage of the device is 15 that the control of the transducers is carried out by two separate commands: writing and reading, which npH- leads to the complication of the entire measuring device as a whole.

A voltage measuring device is known, comprising a counting unit, an indication unit, an analog-code converter, made on a magnetic core with a winding, one end of which is connected to the write and write source buses through the first and second elements and the other connected to the second source bus. records, and with the collector of the transistor, 30

united to the first input of the first NAND element, to the input of the delay line and to the output of the third If element. The emitter of the transistor is connected to the second bus of the charge source, and the base is connected to a voltage divider connected at the charge source. The first input of the third element I is connected to the delay line, and the second input is connected to the source of charging 21.

 The disadvantages include low noise immunity and significant measurement error, because the device has a built-in booster and a speed sensor, as well as a counting unit, made in the form of individual nodes that require individual tuning and each make its own error, which is included in the total error of the measurement device.

The aim of the invention is to improve measurement accuracy and noise immunity.

This goal is achieved by the fact that in a device for measuring voltage, containing a counting unit, a display unit, a converter A, an alog code executed on a magnetic core with a winding, a transistor,

738148 voltage divider, three elements AND the NAND element, a delay line, a pulse generator, four triggers, two additional I-NB elements, and an additional I element are entered. For S, the inputs of the first and second triggers are connected to the starting source bus signals, the unit output of the first trigger — with the second input of the first element and, the unit output of the second trigger — with the first input of the additional element I, the second input of which is connected to the output of the pulse generator, and the output with the control input of the counting unit ICE is associated with the control input of the induction unit and with the R input of the second trigger, the unit output of the third trigger with the second input of the second element I and the first input of the first complementary element AND NONE, the second input of which is connected to the output of the pulse generator , and the output - with the S-input of the fourth trigger, is the same: the output is kottiporo Connected to the second input of the first I-NB element. The zero output of the third trigger is connected with the first Input of the second additional NAND element, the second input of which is connected to one of the outputs of the counting unit, and the output with the R input of the first trigger, with the S input of the third trigger and the installation input of the counting unit. . . The structural electrical circuit of the device is shown in FIG. 1. In FIG. Figure 2 shows the static U1 optic hysteresis loop, explaining the operation of the device. The device for measuring voltage contains a counting unit 1, an indication unit 2, a magnetic core 3 with a winding, elements AND 4-7, transistor 8, elements AND-HE 9, 10, 11, delay line 12, voltage divider 13, triggers 14 -17, 18 impulse generator, 19 trigger signals. The device works as follows. When the signal is started, a start on the 19-start sigal trigger starts 14 and 15 into a single state and elements 4 and 7 are prepared for operation, respectively. 4eg) e §y & A and 4 of the magnetic core 3 during the pre-determined time re-magnetized along the private hysteresis loop in the + W direction to any intermediate value Вг of the recording source (Uy). Through the element And 7, the stable frequency pulses from generator 18 are fed to the input of the counting unit 1. Upon reaching the counting unit 1, the value of the matching counted TPsfslssWai connected to the second HOLU element-HE 11, the last

4 triggers and generates a signal that puts the trigger 14 to the zero state and, acting on the installation input of the counting unit 1, brings it back to its original position. Thus, the trigger 14 determines the state of the recording of the measured voltage (Uy). The AND-NE element 11 also translates the trigger 16, which by the signal from the zero arm, closes the AND-HE element .11, and the signal from the single arm, prepares the AND element 5 for operation. the core 3 begins to re-magnetize to the initial state by the source of de-charging (U. „„.), and the counting unit 1, reset to the initial position by the signal from the element AND-NE 11, begins to be filled anew by stable frequency pulses coming from the generator 18 through the element AND 7. The time interval between at the moment of receiving the readout signal and the moment of the end of the magnetization reversal process of the magnetic core 3 is proportional to the converted voltage, which is converted by the counting unit 1 into a number of pulses proportional to the measured voltage (U), when the process of magnetic reversal of the magnetic core 3 terminates and in the rise, the transistor 8 generates a signal arriving at the first input of the element AND-HE 9, at the second input of which there is an enable signal coming from the unit arm trigger A period 17, which has now been transferred to a single state by a signal from the NAND element 10. The signal from the NAND element 9 is a signal of the end of the readout process, which, arriving at the R input of the trigger 15, brings it to the zero state . The trigger 15 stops the arrival of stable frequency pulses from the generator 18 and the input of the counting unit 1. The signal from the NAND element 9 is also fed to the control, the input of the display unit 2, which gives information recorded on the digital display to the counting block 1, the value of which is proportional to the measured voltage. In order to reduce the error of the converter, a complete remagnetization of the core to the initial state is necessary. These fuctions perform delay lines 12 and element ib. At the moment when the remagnetization process ends, the signal from transistor 8 is fed to the input of the AND-HE element 9 and to the input of the delay line 12. Passing the line, this signal opens the element And 6, a shunt transistor 8, with the magnetic winding

The core is applied to the voltage of the charging source (the magnetic core intensively ends a complete reversal of the magnetization through the longitudinal hysteresis loop.

In order to increase the noise immunity j of the device for measuring the voltage, the device AND-HE 9 is used in the circuit with new connections.

When the indication of the magnetic core EH to YN INDUCTIVE - AQ winding resistance is small and the transistor 8, which reacts to the state of the core, generates a signal that goes to the NAND element, the signal from the single arm of the trigger 17 passes through its other input. at the output of the element IS-NOT 9, there is no signal, because at the moment when the counting unit 1 reaches the value of the corresponding counting bit connected to one of the inputs of the IS-NE element 11, the latter switches to the single state trigger 16, which prepares to slave th NAND 10.

The IS-NE element 10 outputs the signal 25 at the output only with the arrival of the next pulse arriving from the generator 18, since the counting unit 1 changes its state on the falling edge of the pulses arriving at its 30 input.

The signal from the element AND-NOT 10 translates the trigger 17 into one state, preparing for operation the element AND-NOT 9. 35

This ensures reliable operation of the device and increases its noise immunity.

This completes the process of measuring the voltage input to the device -... wa (Uy). Next, the measurement process is repeated - the measured voltage (Uj) is supplied to the device input, the circuit is returned to the initial state, the Start command is given.

The use of the device allows, in comparison with known devices, to use a counting unit as a writing and writing device and a recording device, 50 which significantly improves the measurement accuracy, the use of the first NAND element at the output, the converter and control triggers increase the noise immunity of the device. 55

Claims (2)

1. USSR author's certificate number 244737, cl. G About j 3/00, 1568. 2. Author's certificate. USSR 350165, cl. H 03 K 13 / 2,0, 1970 (prototype), 738148