SU1136229A1 - Process for testing hermetically sealed reed relay - Google Patents

Abstract

THE TEST METHOD OF THE GERCONOBOFO RELAY, according to which a controlling electrical harmonic signal is applied to the winding of the indicated relay, smoothly increases its amplitude and fixes the value of the signal corresponding to the beginning of the periodic closures of the contact details of the reed switch, characterized in that, in order to improve the accuracy and reliability of monitoring by identifying them with the membership of the measured response parameter of the reed switch to the working or resonant frequency range, the test is carried out using two electrical To these channels, for which the second electric channel is set to a control level equal to the fixed signal value corresponding to the beginning of the periodic closures of the contact details of the reed switch, impulses are formed through the first electric channel during the closed state of the contact details of the reed switch, and the second impulses over the duration of the existence of a control electrical harmonic signal at a set level of the Control continue to increase the amplitude of the control of the electric wave signa (A la and in coordination in time or within a predetermined mismatch; the values of the fronts of the generated pulses are considered the measured value of the reed switch tripping parameter located in the working frequency range, the time error of the fronts of the foreshadowed pulses 00 over a predetermined value is considered the measured value of the trigger parameter of the reed switch located in the resonant frequency region.

Description

1n

This invention relates to electrical engineering and is intended to measure electrical parameters of reed relays.

It is known that if, when measuring a parameter - the magnetomotive force (DMS) of the triggering of a reed switch, a signal with a frequency s close to its own frequency (x) (j mechanical oscillations of the moving contact, measured value of the operating parameter of the reed switch the relay drastically decreases and is significantly different from a similar value measured outside the resonance l.

Thus, the measurement of the operating parameters of the reed relays in the resonance region is characterized by the appearance of an additional (frequency) error of so large a magnitude that the measurement loses meaning. In view of this, the frequency range of signals above 0.9 and) is attributed to non-working, in which the use and testing of reed relays is not recommended. However, the known method does not allow to determine in which particular frequency range of the signal the measurement was performed.

The closest to the proposed technical essence is the method of testing reed relays, according to which a control electric harmonic signal is fed to the winding of reed relays, smoothly increases its amplitude and fixes the signal value (trigger parameter) corresponding to the beginning, periodic closures of contact details of reed switch C23.

The disadvantage of the known test method is that it also does not make it possible to establish in which working or working resonance frequency range the measurement is made. If the frequency of the signal used in the measurement turned out to be close to the resonance frequency of the moving contact of the reed switch being tested, then the measured value of the reed switch's response parameter will differ significantly from the operating value due to the appearance of a larger frequency error and is unsuitable for characterization

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suitability of the reed switch for operation.

The purpose of the invention is to improve the accuracy and reliability of the method control by identifying the belonging of the measured parameter to the reed switch to the working or non-working (resonant) frequency range without determining the actual signal frequencies and the natural frequencies of the oscillating contact of the relay.

The goal is achieved by the fact that in the method of testing reed relays, according to which a control electric harmonic signal is fed to the winding of said relay, gradually increase its amplitude and fix the signal value corresponding to the beginning of periodic closures of contact details of reed switch, two electric tests are performed channels, for which a rumbled electrical channel. a control level is set equal to the fixed value of the signal, corresponding to. to the onset of periodic closures, contact details of a reed switch,

0, the impulses are formed on the first electric channel during the closed state of the contact details of the reed switch, and on the second, the impulses during the duration of existence

5 charging the electric harmonic signal at a set level of control, continue to further increase the amplitude of the controlling harmonic signal and when matched in time or misaligned within a given value of the edges of the generated pulses, read the measured value of the reed switch: the relay is positioned in the working area frequencies, and when the time difference of the fronts of the generated pulses above a given value, consider the measured value of the response parameter

0 reed switch located in the region of resonant frequencies.

The test method is based on the fact that, when the reed relay operates in a resonant mode, the duration of contact closure H decreases relative to the exemplary durations ij, measured at the trigger level of the reed switch,

3II

k - time, where F - value of pair2

a reed relay actuation meter at an arbitrary frequency; signal; Fj is the steady-state value of the reed switch activation parameter out of resonance.

In the case of reed relay operation outside the resonance, the energy expended to maintain the positive vibrations of the moving contact with a given amplitude equal to the working contact gap does not depend on the natural frequency of the moving contact and is constant for a specific reed switch instance. Therefore, F: F-1 and t tu, which in turn is determined by the shape of the control harmonic signal. However, near the resonant frequency F: F, 1 1 and, respectively, because of which there is a mismatch in time between the front and rear edges of the pulses with durations t and i.

In addition, when testing a reed switch with a very high quality factor at a signal frequency close to the resonant frequency of a moving contact, relative displacement of pulses {and t is observed due to the appearance of beats, since the moving contact is not synchronized with an hour of this signal of very small amplitude, on its own frequency.

FIG. 1 shows a diagram of testing a reed switch, in FIG. 2, a type of generated pulses at a signal with an amplitude corresponding to (a) and exceeding (b) the srabaty threshold. Vani gerkonovogo relay.

The method is implemented by a typical scheme for measuring the operating parameters of a ger-ramped relay (Fig. 1) containing adjustable excitation unit 1, milliammeter 2, winding 3 and pin 4 of the test relay, display unit 5, for example, made in the form of a dual-beam oscilloscope. The first channel of the oscilloscope is connected to the contact 4 of the reed switch, to the second channel U, the output of the non-corediand comparator 6 is turned on, for example, type 521CA1, with an adjustable trigger threshold, connected by the input to the output of unit 1.

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The test circuit of the reed switch operates as follows.

On the winding 3 of the reed switch relays from block 1, a control electric harmonic signal 7

(Fig. 2a), its amplitude gradually increases and fixes the value of the signal 8, which corresponds to the trigger threshold, to the beginning of the periodic closures of the contact details of the reed-on relay (the moment when on the screen of the oscilloscope 5 the impulses 9 begin to form during the closed contact state) details 4

15 reed relays). The test is carried out through two electric channels, for which the control level 8 of the comparator 6, equal to the fixed value of the contact parts 4 of the reed switch, is set using the regulating element via the second electric channel.

At the same time on the screen of the oscilloscope 5 are formed separately from the pulses 9

25 pulses 10 for the duration of the existence of the value of the control electrical harmonic signal at the set control level 8. Continue further to increase

30 amplitude of the control electrical harmonic signal from block 1 (fig. 26).

When the reed relay operates outside the resonance, the pulse shape 9 practically coincides with the shape of the exemplary pulses 10, time i and i. equal, mismatch, pulse fronts in time otcyTCTByeT. If the measurement is carried out by a signal

40 whose frequency is close to the natural frequency of mechanical oscillations of the movable contact of a reed switch, pulse duration i is 9 in K (FI P is less than duration i: 45 pulse 10 and between the pulse fronts on the oscilloscope screen there is a larger c / cjreM mismatch to the resonance frequency of the moving contact reed switch, the lower

resonance frequency and higher quality of reed relays, as an oscillating system. By the appearance of a mismatch (A above a predetermined value, possible when the reed switch is operating outside the resonance due to inaccurate setting of the control level 8, the parameter value of parameter 2 of the trigger is measured in the non-working (resonant) frequency range by instrument 2. The test method can be implemented using other hardware means, for example, a single-beam oscilloscope with an electronic commutator of channels, or using a standard meter for the time interval between the appearance of two pulses. In addition to measuring the operating parameters of the reed switch, it is possible to evaluate the accuracy of the measured values — they relate to the working or non-working (resonant) frequency range. This improves the accuracy and reliability of the method control compared to the known ones. error) is made on the basis of a single experiment, when an unknown signal is given (arbitrary or directly the one on which the frequency will be controlled, b Without attracting frequency-measuring equipment and removing the amplitude-frequency characteristic of a reed switch. In addition, the proposed method simplifies the procedure for testing reed relays, for example, before commissioning, because it allows you to quickly determine in which mode - normal or resonant - the reed switch will operate from already operating on a controlled periodic action object that is not provided by known methods of testing reed relays without determining the frequency of its resonance.

but

Claims (1)

METHOD FOR TESTING A REEDER RELAY, according to which a control electric harmonic signal is supplied to the winding of the indicated relay, smoothly increase its amplitude and fix the value of the signal corresponding to the beginning of periodic contact closures of the reed relay contact details, characterized in that, in order to increase the accuracy and reliability of monitoring by identifying them as belonging to the measured operation parameter of the reed relay to the working or resonant frequency range, the test is carried out by two electric channels, for which a control level is set on the second electrical channel equal to a fixed signal value corresponding to the beginning of periodic closures of the contact details of the reed relay, pulses are generated on the first electric channel during the closed state of the contact parts of the reed relay, and on the second - pulses during the duration of the existence of the control electric harmonic signal at the set control level, continue to further increase the amplitude of the control electric of a harmonic signal and when matching in time or mismatch within a given value of the fronts of the generated pulses, consider the measured value of the response parameter of the reed relay located in the working frequency range, and when the mismatch in time of the fronts of the generated pulses above the specified value, consider the measured value of the operation of the reed relay in the field of resonant frequencies.