SU849154A1 - Device for measuring electromagnetic relay time parameters - Google Patents

Description

one

The invention relates to electrical engineering and can be used in factory and laboratory tests of electromagnetic relays.

A device for obtaining the response characteristics of a peiae is known, comprising a power source, a pulse generator, an oscilloscope, keys, as well as a current transformer, a sinus-sinus rotary transformer, an amplitude modulator, a power amplifier, detectors, an isolating transformer, a rij rotator

However, such a device is very bulky and difficult. In addition, the process of measuring the temporal characteristics of the relay under study is complicated.

The closest in technical essence to the present invention is a device for measuring the time characteristics of a relay, comprising a power source, a pulse generator, an oscilloscope, keys, terminals for connecting the relay under study, a voltage divider on resistors, a switch, a trigger, an electronic switch, one of whose inputs connected to a voltage divider, and second to the needle-shaped pulse generator

with a calibrated following frequency, the output of the switch is connected to the input of the oscilloscope C2,

However, the known device is characterized by the complexity of the design, inconvenience in operation due to the need to switch from the operation mode to the release mode, which leads to an increase in time

10 measurement and complication of the process of measuring the characteristics of the relay. In addition, in this device there is no possibility of specifying the time parameters of the relay under study under the influence of various contact loads.

The purpose of the invention is to simplify the device and improve its performance, improving the accuracy of measuring the time parameters of the investigated relay under various contact loads.

The goal is achieved by the fact that in the device for measuring the time parameters of the electromagnetic

25 relays containing a power source, a pulse generator, an oscilloscope, switches, a voltage divider on two resistors, terminals for connecting D1MOBILE and fixed contacts and 30 windings of the monitored relay, output

the pulse generator is connected to the synchronization input of the oscilloscope and the inputs of two switches, one of which is connected in parallel to one of the two resistors of the voltage divider, and the other switch is connected in series with to connect the winding of the controlled relay, and parallel to the other resistor of the voltage divider the measurement input of the oscilloscope is connected, and the power source is connected to a voltage divider at the resistors through the terminals connected between the joint to connect the fixed contacts of the monitored relay and the glue th for connecting the movable contact controlled by a relay.

In addition, a series of a contact load controller and a current meter is inserted in series with a voltage divider.

FIG. 1 shows a block diagram of the proposed device} in FIG. 2 - electric circuit of the device; in fig. 3 is a block diagram of a device allowing adjustment of measured parameters in accordance with different contact loads with the help of a contact load controller; in fig. 4d - diagrams of the output pulse of the generator pulses; in fig. 45 — rectangular, cross-section voltage pulses, and ivtjx on the oscilloscope screen; in fig. 5epures of voltage pulses displayed on the oscilloscope screen with a contact load close to the maximum permissible.

The proposed device contains a power source 1, a pulse generator 2, an oscilloscope 3 with a built-in time meter and keys 4 and 5, the key 5 being connected to the winding of the relay 6 under study having a switching contact group 7, and a voltage divider on the resistors 8 connected to the oscilloscope 3. The synchronizing input 9 and the measuring input 10 of the oscilloscope, 3 are connected respectively to the transistor 11 by resistors 12 and 13, forming a key 4, and to the transistor 14 by resistors 15 and 16, forming a key 5. Movable contact, 17, opening contact T 18 and the closing contact 19, form the switching contact group 7 of the relay under study. A resistor 21 is connected to the terminals 20 for connecting the contacts 17-19 and the winding 6 of the relay under study, which, together with the resistor 22, forms a voltage divider. The device also contains a contact load regulator 23.

In FIG. 45, the voltage level corresponding to the closed state of the key 4 is indicated by the voltage level corresponding to the open state of this key — time

delays in opening keys 4 and 5 -; the time from the moment of opening the keys 4 and 5 to opening the contacts 17 and 18 t, the time from the moment of opening the contacts 17 and 18 to the closing of contacts 17 and 19 - t; the bounce time of contacts 17 and 19 - t, the time of unreliable operation of the investigated relay - tg) the time of reliable operation of the relay - t) duration, affecting the winding 6 - t; (the time from the moment of closing the keys 4 and 5 to the moment of opening the contacts 17 and 19 is tg; the time from the moment of opening the contacts 17 and 19 to the moment of closing the contacts 17 and 18 - the time of unreliable release of the investigated relay is t

reliable release time AND

Can test relay - FIG. 5 the time from the moment of opening the keys 4 and 5 to the moment of the final opening of the contacts 17 and 18 is indicated by t) the time from the opening of the contacts 17 and 18 to the moment

contact closure .17 and 19 - t

time Y4

m bounce contacts 17 and 19 - t .;

time of reliable operation of the investigated relay -,; time from the moment of closing the keys 4 and 5 to the moment of the final opening of the contacts 17 and 19 - the time from the moment of opening the contacts 17 and 19 to the moment of closing the contacts 17 and 18 - tjg; bounce time of contacts 17 and 19 - tyg The proposed device works as follows.

The pulse generator 2 produces rectangular pulses, the duration of which exceeds the response time of the tested relay. These pulses are fed simultaneously to the synchronization input 9 of the oscilloscope 3, the start of its 1 sweeping sweep and the built-in time meter, and the bases of transistors 11 and 12, which open after a delay time t. Before they are opened, a voltage plot with a level and is displayed on the screen of the oscilloscope 3.) Due to the flow of current along the circuit plus the power source — resistors 21 and 22 — pins 17 and 18 — minus power source 1.

With the opening of the transistor 11, the resistor 21 is shunted by it, almost the entire voltage of the power supply source 1 is applied to the resistor 22, which is displayed on the screen of the voltage of the lower level U. Through the opened transistor 14, the voltage of the power supply source 1 is supplied to the winding 6 of the relay under study, after which the starting of the relay and moving its contacts starts. Contacts 17 and 18 are in the closed state for a time t

but.

After they are opened, the power supply circuit, the resistor 22 is broken, and the oscilloscope 3 displays a plot of zero level voltage that will be observed for the time tg. When contacts 17 and 19 begin to close, usually accompanied by chatter, the power supply circuit of resistor 22 periodically restores and breaks, which is displayed on the screen of the oscilloscope 3 with short voltage pulses with a UQ level. The chattering phenomenon of contacts 17 and 19 continues for a time t4, at the end of which the transitional resistance between contacts 17 and 19 becomes almost zero, and a voltage level with level Uj is displayed on the screen of oscilloscope 3. The time from the appearance of the voltage on the oscilloscope screen 3 with the level U up to the moment of its secondary stable position t is the time of the reliable operation of the relay under study.

At the end of the pulse of the pulse generator 2, the transistors 11 and 15 are closed:. With the closing of the transistor 11, the resistor 21 is bridged, the voltage drop across the resistor 22 decreases, which is displayed on the oscilloscope screen 3 with a voltage plot with a lower level U. Closing the transistor 14 leads to disconnecting the winding b of the relay under study from the power source 1, after which the process begins releasing this relay. - Contacts 17 and 19 remain in the closed state for a time tg. After they are opened, the circuit of resistors 21 and 22 is broken, and the oscilloscope 3 displays a voltage diagram with a zero level, which is observed during the time tg.

When the closure of contacts 17 and 18 begins, which is also accompanied by contact bounce, the power supply circuit of resistors 21 and 22 is periodically restored and broken, which is displayed on the oscilloscope screen .3 with short voltage pulses of U-x level. At the end of the bounce, contacts 17 and 18, their transitional resistance becomes zero and the voltage and level diagram is displayed on the screen of oscilloscope 3. .

The voltage plots depicted in FIG. 4, have the form of rectangular pulses. However, with an increase in the contact load, and especially when it is approached to the maximum allowable pulse shape, it changes significantly. A transitional resistance between the contacts begins, which occurs when they are closed and opened. At the same time, the tops and the bases of the pulses appear rounded.

The reliable turn-on time (shut-off) is significantly increased.

(t. and t, 2 (j in Fig. 5 in comparison with t and t.j in Fig. 45). Therefore, in a number of important schemes, before installing the structure, it is necessary to clarify the timing of the relay for a particular contact load.

A contact load regulator 23 with its meter, for example, a rheostat with an ammeter (FIG. 3) is connected in series with voltage divider 8. This allows the operator to quickly

0 install any required contact load, without changing the device circuitry, which speeds up the measurement process.

The use of the invention makes it possible to increase the accuracy of measuring the time parameters of electromagnetic relays during their production and use, as well as to simplify the used control equipment.

0

Claims (2)

1. A device for measuring the time parameters of an electromagnetic relay containing a power source, a pulse generator, an oscilloscope, switches, a voltage divider and two resistors and terminals for connecting moving and fixed contacts 0 and windings of the controlled relay, characterized in that, in order to simplify the device and increase its performance, the output of the pulse generator is connected to the synchronizing input of the oscilloscope and the input of two switches, one of which is connected in parallel to one of the two voltage divider resistors and the other switch is on in series with terminals for connecting the winding of the monitored relay, and the oscilloscope measuring input is connected in parallel with another resistor of the voltage divider, and the power supply is connected to divisor of voltage on the resistors connected to each other through terminals for connecting the fixed contacts controlled by the relay and the mobile terminal for connecting 0 contact controlled relay. 2. The device according to claim 1, characterized in that, in order to improve the measurement accuracy of the time parameters of the monitored relay at different contact loads, five A series circuit is inserted from the contact load controller and a current meter connected in series with a voltage divider. About Sources of Information taken into account in the examination 1. Author's certificate of the USSR 300902, cl. H 01 H 47/00, 1969. 2. Authors certificate of the USSR 5 214672, cl. H 01 H 47/00, 1966. g