SU1453470A2 - Method of testing a sealed-contact relay - Google Patents

Abstract

The invention relates to electrical engineering and is intended to measure the electrical parameters of reed relays. The purpose of the invention is to expand the functionality of the method by providing its application to a wide frequency range of the control signal without recalculating the predetermined duration of the error in time of the fronts of the generated pulses. According to the method, a control harmonic signal is fed to the winding of the reed-on relay and increases its amplitude before the first contact closure. From this moment, pulses are started to form on the first (by the relay contact) and second (using an additional comparator) electrical channels, setting the same thresholds and pulse duration in both channels. The ratio of the pulse duration in the second channel to the pulse duration in the First is measured with a further increase in the amplitude of the control signal —i, if this ratio is prior. unit, it is believed that the parameters were measured at a signal frequency close to the natural frequency of the mechanical oscillations of the relay contact. 2 Il. § (L

Description

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The invention relates to electrical engineering and is intended to measure electrical parameters of reed relays and is an improved

the invention according to auth. No. 113622

The purpose of the invention is to expand the operational capabilities of the method by providing the possibility of it: application in a wide range of frequencies: that of the control signal without re-calculating the predetermined duration of the error in time of the fronts of the generated pulses,

I Fig. 1 shows the test circuit of a reed switch; in FIG. 2 -. | type of generated pulses and time intervals; when testing a gerkono JBoro relay outside (a) and in the zone (b) of resonance frequencies,

J. The method is implemented by a typical scheme for measuring the operating parameters of a reed iBoro relay (FIG. 1) containing a controlled excitation unit 1, milli

2, winding 3 and pin 4 are 25 capacitors. The comparator 12 of the relay being tested, the display unit 5, is only selected under the condition U ,, U, Example, made in the form of an element: UNABILITY AND a signal lamp. The pulses in the first electrical channel are formed by the contact 4 of the relay, the JQ in the second electrical channel - by a diverterless comparator 6, for example, type 52 ICAI, with an adjustable threshold. Additionally, the first 7 and the second 8 integrat are entered into the scheme, which corresponds to the ratio with / t 1,

According to the proposed method, it is continued to further increase the amplitude of the control harmonic signal from block 1 and control the ratio of the pulse durations in the second and first channels with the help of a comparator 12 (the ratio-voltage

Uj, to U |), When operating outside the region of the tori (measuring the duration of pulsed resonance frequencies (Fig 2, a)

sa) with bit switches, an element OR-HE 9, whose inputs are connected to the first and second electrical channels, and the output to the inputs of bit Q switches of the integrators 7 and 8, The outputs of the last. Through the amplitude detectors 10 and 11 are connected to a ratio meter, as a one-timecontainer relay with a return coefficient close to one (levels 14 and 15 are the same), or less than one, respectively, the ratio of pulse durations tg / t, 1, When the relay is operating in the resonance region (Fig. 2.6) pulse duration t in the first channel with increasing the amplitude of the control harmonic signal lags behind the growth rate of the pulse duration in the second electrical channel, generated by the comparator 6, so their ratio is independent of the frequency (period) of the control signal on which the relay is tested. This ensures the application of the method in an arbitrary signal frequency range (unknown), simplifies the application and makes it easy to automate the testing of large batches of relays. In addition, the reliability of the method is improved when testing reed relays

Comes to the controller 12,

The relay is tested as follows.

A winding relay 13 is fed to the winding 3 of the tripping relay from block 1 (FIG. 2), its amplitude is gradually increased and a threshold value 14 is detected by the milliammeter 2 (the return parameter corresponds to level 15), when the contact part 4 of the relay is reached begin to close, which leads to the operation of the element 5. With the help of the regulating element set the level of control of the computer

Ratio 6, equal to the fixed threshold 14 to trigger the relay, so that the element 5 stops functioning (the pulse durations in the first and second channels are equalized). The comparator 6 generates pulses 16 through the second electrical channel, their duration tg is converted by the integrator 8 into voltage 17, the level of which U is stored by the amplitude detector 11, and by the contact 4 of the reed switch, pulses 18 are formed through the first electrical channel, their duration t. converted by integrator 7 to voltage 19, the level of which U is memorized by amplitude detector 10, integrators 7 and 8 are periodically zeroed with an OR-NOT 9 element, which is triggered during periods of no pulses on both electrical channels and opens the bit switches through which I integrate0

Schie capacitors. Comparator 12 switches only if U ,, U

h something corresponds to the relation with / t 1,

According to the proposed method, it is continued to further increase the amplitude of the control harmonic signal from block 1 and control the ratio of the pulse durations in the second and first channels with the help of a comparator 12 (the ratio-voltage

Uj, to U |), When operating outside the region of resonant frequencies (Fig 2, a)

Q

five

0

five

reed relays with a return coefficient close to unity (levels 14 and 15 are the same), or less than one, respectively, the ratio of pulse durations tg / t, 1; When the relay is operating in the resonance region (Fig. 2.6), the pulse duration t increases in the first channel, with an increase in the amplitude of the control harmonic signal, it lags behind the growth rate of the pulse duration in the second electrical channel, generated by the comparator 6, therefore their ratio is independent of the frequency (period) of the control signal on which the relay is tested. This ensures the application of the method in an arbitrary signal frequency range (unknown), simplifies the application and makes it easy to automate the testing of large batches of relays. In addition, the reliability of the method is improved when testing reed relays

with a very high quality factor at a signal frequency close to the resonance frequency of the moving contact, since the effect on the test results does not affect the relative time shift of the generated pulses due to the appearance of beats.

Claims (1)

Invention Formula Test method reed relays auth.St. No. 1136229, which is distinguished by the fact that, in order to expand its operational capabilities by enabling it applications in a wide frequency range of the control signal without recalculating the predetermined error duration in time of the fronts generated by the pulses, measure the duration of the pulses along the first electrical channel, measure the duration of the pulses along the second electrical channel, determine the ratio of the second measured value to the first and if the ratio obtained is greater than one, the measured value of the reed switch relay response parameter is located in the region of resonant frequencies. Fie.2