SU51249A1 - Strobe device for checking and adjusting electric meters - Google Patents

Description

Ulge knows a device for stroboscopic calibration of electric meters, consisting of a light pulse sensor and a differential device driven by an electric motor in the form of a structurally connected DC voltmeter and an electrodynamic wattmeter. The voltmeter serves as an electric tachometer for measuring the frequency of light impulses, and a wattmeter for measuring the power transmitted through a meter being turned on. The method of calibrating the counters using such a device consists in that by adjusting the frequency of the light pulses, the stroboscopic image remains on the disk of the counter being turned on, and then the counter error is determined by the differential meter readings :.

The device described, however, has a number of disadvantages. Thus, the rotational speed of the engine of the sensor of light imulses may fluctuate, causing instability of the stroboscopic effect; Variations in the mains voltage cause unequal changes in the rotational speed of the motor and the meter being turned, which also affects the stability of the stroboscopic image. Further, the indications of the differential device will include errors caused by inaccurate proportions between the voltage at the terminals of the DC generator and its rotational speed, i.e. the inaccuracy of the electric tachometer, and the need to measure two different quantities at the same time as the gradual differential device, the frequency of the light pulses and the electrical power.

The proposed device is free from these shortcomings, as a result of which it provides high accuracy of meter calibration. Like the device described, it consists of a sensor of light pulses and a differential instrument indicating the error of the counter to be counted at the moment when the stroboscopic image on the disk of this counter is stationary. However, it differs from the described device in that as a sensor of light impulses a control counter is used, and the differential device consists of two wattmeters of the same type, one included in the test subject's value, and the second one of the control counter.

The attached drawing shows two options for switching on the devices of the device proposed; The spike C and C and the control counter K are connected to spikes I and U through adjustment resistance. The differential wattmeter B systems are included so that system 1 measures the power applied to the control counter K, and system 2 applies to the counters CC .

In this case, all successive windings of meters and wattmeters can be connected in series, as shown in fig. 1, and the voltage at the terminals of the test counter and the first wattmeter can vary independently of the second wattmeter and the counters under test, or all the windings of the wattmeter voltage and counters are connected to a common one, and the current in a series circuit of the control meter and the first wattmeter can vary depending on from the second wattmeter and the meters being tested (Fig. 2). In order to increase the accuracy of measurements at low loads, wattmeters may have additional pedestrivial windings. For simplicity, the pa figures have omitted the instruments used to establish the test mode.

In the production of the test of FIG. 1, the voltage is varied, and FIG. 2 - current strength in the control or test counters until the apparent (stroboscopic) movement of the marks on the disk of the counter being counted stops. If, for example, the test counter is seeshit, then it will have to increase the speed of the control counter, i.e., increase the power delivered to the letter. At the same time, the torque of the first wattmeter will increase and the pointer and errors will indicate the power difference. By multiplying by a constant, you can immediately determine the exact error. With a mass surface of cii plBtoifi;: - with the same power and the power, the crystal can be scored as a percentage of the error.

The subject matter of the invention.

A stroboscopic device for checking and adjusting electric counters by equalizing the rotational speed of two counters, the control and the test, the first of which is a sensor of light pulses, pre-trigger for illuminating the stroboscopic marks, and on the disk of the counter-countable counter, in which a differential measuring indicator is used as an indicator Iribor, characterized in that, in order to use a differential instrument to directly indicate the relative error of the device being tested etchika as separate systems device isiolzovapy two wattmeter odnotiinyh included - one in tsen koitroliogo as well. the other is in the range of verifiable meters.

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