SU1166303A1 - Device for automatic measuring of digital voltmeter drift - Google Patents

Abstract

A DEVICE FOR AUTOMATIC MEASUREMENT OF DRIFT DIGITAL VOLTMETERS, containing a source of exemplary signals, connected to an invertedly switched on switch of exemplary signals, the outputs of which are connected to the measuring inputs of controlled digital voltmeters, and the control input to the first synchrometer input, which is the surface of the voltmeter, which is connected to the themes. the measurement time, the first commutator of the analog signals is connected in series, the time-code converter is a voltage, the second comm Ogove signals and multi-channel recording volt meter, the inputs of the first analog switch connected to inputs of controlled digital voltmeters and control inputs of the first and second analog switches are connected to second and third outputs respectively synchronometer.

Description

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The invention relates to automated information-measuring systems for monitoring the parameters of digital measuring devices and can be used, in particular, to measure the drift of digital voltmeters, which operate on the principle of the pulse conversion time of a measured signal, at any ratio between the standard deviation of the random error component and step quantizing.

A device for measuring the drift of digital voltmeters is known, which contains an exemplary signal source connected by an output to an input of an adder, the output of which is connected to an input of a code comparison unit through a monitored digital voltmeter, reversible counters interconnected with logic circuits AND, OR, and triggers, a code converter. The output of which is connected to the recording recorder f1J.

However, this device has a large measurement time, due to the need to change the input sample signal Vjjj until the adjacent readings N and N ± q of the monitored device coming from the code-voltage converter to the input of the adder appear. In addition, each change in the reference signal requires an additional number of measurements to determine the probability of the occurrence of code N, for example, in the sequence N,, where q is the quantization step of the monitored device.

Closest to the invention to the technical essence is a device for automatically measuring the drift of digital voltmeters, containing a source of reference signals, the outputs of which are connected to the switch inputs, a program block, a comparison unit, two inputs of which are connected respectively to the outputs of the switch block and the program output of the program sample block, a synchronometer associated with a command docking and interruption unit, a probabilistic analysis unit, a combination adder, an inversely connected switch and a comm radiating board, the output switch is coupled to an input of a switch included inversely associated

663032

with a switchboard, the outputs of which are connected to the inputs of the switch unit, the a-output of the comparison unit is connected to the probability analysis unit, the outputs of which are connected to the corresponding inputs of the source of reference signals through the docking unit and to the first input combinational adder, the second input of which is connected to the output of the maximum error tolerance of the program block, and the third - with the output of the output switch, the switch block and the program block Borki L2 J.

However, the known device also has a measurement time due to a large number of measurements when changing the reference signal and determining the probability of occurrence of the monitored code.

The purpose of the invention is to reduce

5 measurement times.

The goal is achieved by the fact that a device for automatically measuring the drift of digital voltmeters, containing a source of

Q nickname of reference signals connected to an inverse switch of reference signals, the outputs of which are connected to the meter. The control inputs to the first input of the synchronometer are additionally connected in series with the first analog signal switch, time-to-voltage converter, second analog signal switch, and a multichannel self-recording volt meter, with the inputs of the first analog signal switch connected to the input dami monitored digital voltmeters, and the control inputs of the first and second switches of analog signals are connected to the second and third sync outputs pressure gauge, respectively.

FIG. 1 shows a block diagram of the proposed device; in FIG. 2 - timing diagrams explaining the operation of the device .. 5 The device contains a source of 1 exemplary signal, connected via an inverted switch 2 exemplary signals to the inputs of monitored 3.1-Z.p digital voltmeters connected in series with the first switch 4 analog signals, converter 5 time - a voltage code, a second switch 6 of analog signals and a multichannel recording recorder voltmeter 7, a synchronometer 8, the corresponding outputs of which are connected to the control inputs of switches 2, 4 and 6. FIG. 2 shows time diagrams explaining the process of extracting a start-stop signal from a monitored device, limited by the beginning and end of the measurement, where the time intervals correspond to the 04-start-stop signal T for the characteristic, b-the start-stop signal Tj for the right characteristic B - output of the quantized DF controlled , -v- to the output of the time transformer, code-voltage, Ent (N,) is the whole part of the number N corresponding to the indications of the DV checked, Fr () is the fractional part of N. carrying information about the location of ca start-stop signal in the quantization step. The device works as follows. When measuring the drift of digital voltmeters Z.p from the output of the source of 1 exemplary signals, an exemplary signal VQ is received. From the three outputs of the synchronometer 8 to the inputs of the inversely switched on switch 2 exemplary signals and the first 4 and second 6 switches come the signal to connect the inputs and outputs of the first controlled digital voltmeter 3.1. The digital voltmeter 3.1 measures the reference signal V ... During the measurement time, a time interval is formed at the output, limited by the start and end points of the measurement (start-stop signal), which is fed through the first switch 4 analog signals to the input of the converter 5 time-voltage-voltage . In the time-to-voltage converter 5, the number of pulses of the start-stop signal is counted. At the same time, the frequency of the additional quantizer in the converter 5 is time-the-voltage code is chosen in such a way that it is multiple, where m 1,2,3 ... The resulting code in the converter 5 is time-the-voltage code corresponds to the numbers EntCN p and Fr ( N), where EntCN P is the readings of a monitored digital voltmeter 3.1, Fr (N) carries information about the location of the end of the start-stop signal in the quantization step .q .. To the voltage, the time interval is converted depending on the required strength of the measurement of the drift of the digital voltmeter 3.1. So, for example, if the latter has a discrete step, 1 µV, i.e. built on six tetrads, then the converter 5 time -code-eg, a hot one can be built, for example, on eight tetrads. Then a voltage is formed at its output (N, J + Fr (NJ, l-rf where Fr () corresponds to information obtained with discreteness q, 0.001 µV. The voltage-voltage comes from the output of the converter 5 through the second switch 6 analog signals to the corresponding code of a multichannel recording voltmeter 7, which registers the drift value of the monitored digital voltmeter 3.1. In this case, the drift is recorded from a single measurement. After the drift of the monitored digital voltmeter 3.1 is recorded from the synchronous output The meter 8 to the input of the invertedly switched on switch 2 of the reference signal and the first 4 and second 6 switches of the analog signals receives a signal to connect the next monitored voltmeter 3.2. Thus, the drift of the monitored digital voltmeters 3 is measured. , the measurement of the drift of the monitored digital voltmeter Z.p is repeated. Thus, this device makes it possible to measure the drift of digital voltmeters with the required accuracy.

which depends on the bit size (shorten the measurement time) of the time –code converter –– for example, by reducing the number of measurements, and increase the output. in the controlled point.

Claims (1)

DEVICE FOR AUTOMATIC MEASUREMENT OF DIGITAL VOLTMETERS DRIFT, containing a reference signal source connected to an inverse switched reference signal switch, the outputs of which are connected to the measuring inputs of monitored digital voltmeters, and the control input to the first input of the synchrometer, characterized in that time of the measurement time, the first analogue signal commutator is connected in series, the time-code-voltage converter, the second analogue commutator x signals and a multichannel recording voltmeter, the inputs of the first analog signal switcher connected to the inputs of the controlled digital voltmeters, and the control inputs of the first and second analog signal switchers connected to the second and third outputs of the synchronometer, respectively. * 1166303