SU369501A1 - HIGH-VOLTAGE MEASURING DEVICE - Google Patents

Description

one

The invention relates to a measurement technique, in particular to a technique for measuring electrical resistances.

A high-voltage measuring device is known, for example, an electrical resistance meter, the measuring circuit of which is a series connection of a voltage source, a measurement object and synchronously modulated low-voltage resistance elements — a measure of resistance and an exemplary divider with an equilibrium indicator across the separation capacitor.

The measured resistance is determined by this meter in accordance with the relation:

x. (1 + “); (eleven

where is the resistance of the measurement object, Ko is the resistance of the measure, Ri / R2 is the ratio of the shoulders of the reference divider, Ri and Rz are its high and low voltage arms, respectively. A disadvantage of the known meter is: a comparative complex switching circuit that ensures synchronism of modulation of the measure and divider, the need to use two keys to modulate the measure and divider respectively, the presence of an offset scale in the instrument by the value of the resistance of the divider.

To ensure synchronous modulation of the current divider and demodulation of its output

voltage, simplify switching connections and create a scale of the device corresponding to the scale of a single bridge, in the proposed device the point of connection of the object of measurement and the high voltage and voltage ratio measures

and the connection point of the low-voltage arms of the ratio measure and the divider are connected via a modulating switch, and the indicator of the equilibrium of the measuring circuit through the control channel by dependent elements connect to the connection point of the arms of the ratio measure.

The described device is shown in the drawing, where: / is a voltage source, 2 is a measurement object with resistance Rx, 3 is a measure of resistance with resistance about 4 is an exemplary divider, an adjustable measure of relationship with resistance and resistance of its arms Ri / Rz, 5 is separation capacitor, 5 — modulating switch, 6 — indicator of equilibrium of the measuring circuit, 7 and 5 — channels for controlling resistance measures and ratios, respectively. At the moment of chain equilibrium (no modulation with key switching frequency 5), the ratios of the measuring circuit are defined as AO-x A2 AO Rx + Ro + Ri + 2 x + 0 - where Yau is made in the form of a resistance box, with a variable division factor. The scale of the device 3 corresponds to the scale of a conventional single bridge. Thus, instead of two keys, as in the known gauge in the proposed device, one key is used, which simplifies the implementation of the instrument and the reference system of the measured value. Subject of the Invention A high-voltage measuring device (e.g., a resistance meter) comprising a high-voltage divider formed by a measuring object connected in series (high-voltage arm), a low-voltage measure with modulated resistance, a low-voltage shoulder with dependent resistance, a balance indicator for measuring circuit, a control channel for the dependent resistance of the low voltage shoulder (or a dependent measure of relation-1), characterized in that, in order to provide synchronous modulating the current divider and demodulating its output voltage, simplifying switching connections, the connection point of the measurement object and the high voltage arm of the ratio measure, and the connection point of the low voltage shoulder ratio measures and the dividers are connected via a modulating switch, and the equilibrium indicator of the measuring circuit through the control channel is dependent elements connected to the point of connection of the shoulders of the measure relation.