Counter is an induction system and is integrated over time of electrical measuring instruments. Principle of operation - the interaction of magnetic fields of currents flowing through two coils, the magnetic field current induktiruemogo in an aluminum disc, located between the windings. Measuring the mechanism of induction of 1 - current coil, 2 - coil voltage, 3 - aluminum disc, 4 - permanent magnet. The device is a meter - Connection for power consumers, 2 - clamps to connect to the network, 3 - current winding, 4 - permanent magnet, 5 - worm screw 6 - coil voltage, 7 - shaft, 8 - aluminum disc, 9 - housing. The main units are el.schetchika coil voltage and current, the aluminum disk 3 is fastened to the axle, axle bearings - thrust bearing and bearing, permanent magnet. C-axis associated with the gear counter mechanism (figure below). Electromagnet 1 contains W - shaped magnetic core, the middle rod is located multiturn coil of thin wire that is included in the voltage U parallel load N. For a nominal voltage of 220 V winding coil voltage is typically 8-12 thousand turns of wire with a diameter of 0.1 - 0 , 15 mm. Current coil through which the full load current is usually the number of ampere-turns within 70 - 150, ie, at nominal current 5 A winding includes from 14 to 30 turns. Complex parts, consisting of sequential (current) and parallel (voltage) windings with their magnetic circuits, said counter rotating elements. Counter mechanism. 1 - axis of the measuring mechanism, 2 - Transmission system zupchatyh 3 - clips counting mechanism current flowing in the winding voltage creates a shared variable matnitny flow voltage circuit, a small portion of which (worker thread) and suppresses aluminum disk located in the gap between the two electromagnets. Most of the magnetic flux through the closed circuit voltage shunts and side rods are magnetic (non current), which is divided into two parts and is required to create the desired phase angle between the magnetic fluxes circuit voltage and the load circuit (a circuit). Magnetic flux circuit voltage is directly proportional to the applied voltage (supply voltage). Load current flowing through the current windings, creates a variable magnetic flux, which also crosses the aluminum disk and closes the magnetic shunt of the upper magnetic core and partially through the side rods. A minor part (non current) is closed through protivopolyus on crossing the disk. Since the magnetic circuit winding current has a U-shaped structure, its magnetic flux crosses the disc twice. Currents flowing through the windings of the voltage and current variables create the magnetic fluxes that cross the disk counters. According to the law of electromagnetic induction, alternating magnetic fluxes of both windings at the intersection of the disc, suggest it EMF, under which the disk appear relevant eddy currents. The interaction of magnetic flux coil voltages and eddy current on the magnetic flux current winding and on the other side of the magnetic flux current winding and eddy current from a winding voltage, there is the electromechanical forces that create the torque acting on the disc. This moment is proportional to the product of these magnetic fluxes and the sine of phase angle between them. A permanent magnet is mounted in the counter to create a braking torque in the counter. The magnetic field lines of the magnet, crossing the disc, suggest it additional emf is proportional to the frequency of rotation of the disk. This voltage in turn causes the flow to drive the eddy current, whose interaction with the flow of a permanent magnet gives rise to an electromechanical force directed against the motion of the disk, ie leads to the creation of brake torque. Adjustment of the braking torque and hence speed disk to produce by moving a permanent magnet in a radial direction. When approaching a magnet to the center of the disk rotational speed decreases.
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