DEVICE FOR MEASUREMENT AND INDICATION OF LIMITING LEVEL OF LIQUID OILS, LIQUEFIED NATURAL GAS IN OPAQUE RESERVOIRS Russian patent published in 2016 - IPC G01F23/26 

FIELD: test and measurement equipment.

SUBSTANCE: invention relates to instrumentation and can be used in various industries for measurement and indication of a limiting level of dielectric fluids, for example, the level of liquid oils, liquefied natural gases, in particular, stored in opaque reservoirs. Device comprises electrically interconnected: a self-excited quartz generator of high-frequency pulsed oscillations on a transistor, a measuring circuit made on a transistor, which is an amplifier, which measuring circuit comprises a diode in the reverse direction and parallel with the diode there is a resistor, capacitive electrodes, a measuring instrument, a power supply source, a diode voltage stabilizer. Capacitive electrodes used are inductance coils wound with a copper wire on insulating bases in one layer by bifilar method, herewith two windings of each inductance coil are connected in parallel. Device contains a four-cascade DC amplifier made on transistors and diodes connected in series. One capacitive electrode of the sensor is connected to a collector of the measuring circuit amplifier transistor, the second capacitive electrode of the sensor is connected to one diode cathode and the other diode anode. Anode of the first diode is ″grounded″. Second diode cathode via a switch and the series-connected resistor is connected to the transistor base of the direct current amplifier of the first cascade. Third cascade of the direct current amplifier comprises series-connected: two diodes, herewith the diodes are connected in the reverse direction, one output of the diodes is connected to the transistor base of the direct current amplifier of the third cascade, the second output of the diodes is "grounded". Measuring instrument used is a light indicator made on a LED. One output of the light-emitting diode is connected to the collector of the direct current amplifier transistor of the fourth cascade, the second output of the LED via the resistor is connected to the power supply source, which is made with low supply voltage.

EFFECT: technical result is wider field of application of the known device and higher safety of measuring while simultaneously increasing the measurement accuracy and manufacturability, as well as simplifying the design.

1 cl, 1 dwg