SU508674A1 - Hydrostatic level - Google Patents

Description

cauldron), connected to the vessel corpus 1 with a common bus and to the electrode 2 with a signal output.

The level works as follows.

The generator generates square-wave pulses, stabilized by the frequency and the o-amplitude. At one meter of the oscillation half-periods of the oscillator, the capacitance of the level sensor along the circuit occurs: signal generator, electrode 2, electrode 3, diode 5, capacitor 6, vessel body 1, common generator bus.

At the other half-period of oscillations of the generator-and the level sensor capacity is discharged along the circuit: signal output of the generator, electrode 2, electrode 3, diode 4, vessel body 1, common generator bus.

A periodic charge of the capacitor 6, which occurs at this, causes its discharge current through milliammeter 7, the arrow of which is deflected. Since the capacity of the sensor depends on the level of the working fluid level, the flow through the milliammeter also depends on the level h of the liquid.

It is well known that

I c. and f

where / is the current flowing through the milliammeter and causing a proportional deviation, the arrow of the milliammeter;

C is the capacitance of a fluid level sensor formed by electrodes 2 and 3;

and - sweep of the generator voltage supply;

/ - alternating current frequency of the generator. So-as (h), (/ i). The readings of the milliamperemeters associated with each of the communicating vessels are read, after which the elevations are calculated by subtraction. It is advisable at the same time to have the milliammeter scale, calibrated in units of length (level height). Since electrode 3 is shielded by electrode 2 from the vessel body 1, the capacitance between this electrode and the vessel is very small and practically does not shunt the common connection point of dis 4 and 5 and electrode 3, which increases the level sensitivity.

Claims (1)

Invention Formula A hydrostatic level containing interconnected vessels filled with working fluid, electrodes of capacitive level sensors placed in them, alternator connected to one of the electrodes of the sensor and to one of the electrodes of the capacitor included in the measuring circuit with two diodes connected in series, in parallel which includes a DC meter, shunted by a capacitor, characterized in that, in order to increase the sensitivity, to the common connection point of the diodes is connected Electrode capacitance sensor whose surface o.hsachena other electrode, coaxial electrodes cylindrical shape.