RO91042B1

RO91042B1 - Method and device for testing a centrifugal relay

Info

Publication number: RO91042B1
Application number: RO115598A
Authority: RO
Inventors: Stelian Pascanu
Original assignee: îNTREPRINDEREA "ELECTROMOTOR"
Priority date: 1984-08-31
Filing date: 1984-08-31
Publication date: 1987-03-01
Also published as: RO91042A2

Abstract

Inventia se refera la o metoda si la un dispozitiv pentru testarea unui releu de pornire, centrifugal bipozitional, montat pe axul unui motor asincron monofazat. Metoda, conform inventiei, prevede compararea a doua nivele de tensiune continua obtinute prin injectarea unui curent constant în înfasurarile statorului motorului separarea componentei slternative a tensiunii de componenta continua, defazarea ei cu o jumatate de perioada si însumarea continua, defazarea ei cu o jumatate de perioada siînsumarea cu semnalul complect obtinut la bornele statorului motorului format din componenta alternativa nedefazata si componenta continua defazarea ei cu o jumatate de perioada si însumarea cu semnalul complet obtinut la bornele statorului motorului format din componenta alternativa nedefazata si componenta continua, compendsarea celor doua componente alternative si afisarea rezultatului compararii obtinut sub forma a doua nivele, un nivel aproximativ nul corespunzator unui releu decuplat. Dispozitivul, conform inventiei este constituit dintr-un generator de curent constant o cale de semnal directa si una defazata, ambele fiind conectate la intrarea neinversoare a unui sumator în configuratie neinversoare, a carui iesire este legata la intrarea neinversoare a unui comparator, pragul de comparatie fiind stabilit cu un potentiometru la intrarea inversoare.The invention relates to a method and to a device for testing a bi-phase centrifugal starting relay mounted on the axis of a single-phase asynchronous motor. The method according to the invention provides for the comparison of the two continuous voltage levels obtained by injecting a constant current into the stator windings of the motor, separating the component of the continuous component from the continuous component, its phase-out by half a period and the continuous summing, its phase-out by half a period and the complex signal obtained at the motor stator terminals formed by the undistributed alternate component and the component continues its phase shift by half a period and the summing with the fully obtained signal at the motor stator terminals consisting of the non-differentiated alternate component and the continuous component, the computation of the two alternative components and the display the result of the comparison obtained in the form of two levels, an approximately null level corresponding to a disconnected relay. According to the invention, the device consists of a constant current generator, a direct and a failed signal path, both of which are connected to the noninverting input of a non-invasive configuration, the output of which is connected to the non-inverse input of a comparator, the comparison threshold being set with a potentiometer at the inverting input.