DC SENSOR WITH ISOLATION Russian patent published in 2014 - IPC G01R19/00 

FIELD: measurement equipment.

SUBSTANCE: invention relates to the field of measurement equipment. A DC sensor with isolation comprises a measuring shunt, the first output of which is connected to the common power supply bus, and the second one - to a load, an operational amplifier (OA), a four-winding transformer, the first winding of which via the first diode is connected to the input of the first filter, the output of which is the output of the device, the second winding of the transformer via the second diode is connected to the input of the second filter, the positive output of OA power supply is connected to the plus power supply bus, and the negative one - to the common power supply bus. The sensor also comprises two resistive voltage dividers with equal division ratios; the first divider is connected between the plus power supply bus and the second output of the shunt, and the second one - between the plus power supply bus and the common bus; the inverting input of the OA is connected to the output of the first divider, and the non-inverting one - to the output of the second divider; the positive output of the second filter via the introduced resistor is connected to the non-inverting input of the OA, and the negative one - to the inverting input of the OA. A capacitor is introduced into the device, which is connected between the output and the inverting input of the OA; a p-n-p- transistor is introduced, the emitter of which is connected to the first output of the shunt, the base via the resistor - to the OA output, and the collector - to the input of the introduced RC-filter; the output of the RC-filter is connected to the power supply buses of the blocking generator, and newly introduced diode, two resistors, a capacitor and a transistor.

EFFECT: increased reliability, noise immunity.

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