FIELD: electricity.
SUBSTANCE: device comprises a three-phase electronic electric counter properly connected via a lead to two phases and a zero conductor of a power transmission line, and its phase outlets are connected to a load via a unit of packaged automatic safety fuses - circuit breakers. Besides, it includes a unit of load currents compensation, comprising the following components connected to the outlet of one of operating phases: a step-down transformer with a controlled transformation ratio, and a controlled load, for instance, in the form of a rheostat, in the circuit of which there is an amperemeter installed. Voltage on the controlled load is measured with a voltmetre. The secondary winding of the step-down transformer is connected to a current circuit of a free phase pair of clamps of the three-phase electronic electric counter so that current in this current circuit is oppositely directed relative to current direction in other phase current circuits. A phase conductor supplying to the unit of load currents compensation is additionally connected to the secondary winding of the step-down transformer.
EFFECT: simplified procedure for assessment of sensitivity of an electronic three-phase electric counter to low variations of load current in a wide range of current consumed by a load, considerable reduction of measurement time.
1 dwg
Authors
Dates
2013-02-10—Published
2011-09-05—Filed