SU1397857A1 - Device for testing electric strength of insulation - Google Patents

Description

(21) 3944798 / 24-21

(22) 08/19/85

(46) 05.23.88. Bul № 19 (72) S.L.Luchkin, E.L.Torkhov, N.V.Ponosov, A.I. Litvinenko and N.N. Lisitsin

(53) 621.317 (088.8)

(56) USSR Copyright Certificate No. 617752, cl. G 01 R 31/02, 1978.

USSR author's certificate 758017, cl. G 01 R 31/14, 1980.

(54) DEVICE FOR TESTING ELECTRIC INSULATION STRENGTH

(57) The invention relates to electrical measuring equipment. The device for testing the dielectric strength contains a test voltage transformer 1, a disconnecting unit 3, a section switching unit (B) 5, a current sensor 7, B 11 switching tires, B 21-23 switching, 12-17, measuring B 24, threshold element 52. The invention reduces testing time by simultaneously monitoring circuits of different test voltages. 1 з, п, ф-л, 1 Il.

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11397857

The invention relates to a measurement technique and can be used to control the installation of electrical installations and the electrical strength of the insulation.

The purpose of the invention is to reduce the time spent on testing due to the control of the circuits with various test voltages with simultaneous connection.

The drawing shows a diagram of the device.

The device contains a test voltage transformer 1, successively with the primary winding 2 of which the disconnection unit 3 is turned on. The winding 2 is connected to an alternating current source.

The secondary winding sections are interconnected through switches 20–4 4.1–4.6 of the section switching unit 5. The section switching unit 5 has a common output 6 of the secondary winding, which is connected to the current sensor 7, and 25 also has leads 8-10 according to the number of Test Voltage Ranges.

The code of the current sensor 7, as well as the ly-water 8-10, are connected to the corresponding inputs of the switching unit 11 of the 30 Tires. The drawing shows the switching unit 11 of three pairs of tires 12 and 13, 14 and 15, and 16, 17, while the switching unit 11 It has three pairs of contacts 18.1, 18.2, 19.1, 19.2 and 20.1, 20.2, which form: an even group - contacts 18.2, 19.2, 20.2 and odd - contacts 18.1, 19.1, 20.1.

The normally open contacts of the even group are connected together 0 and connected to the primary winding of the current sensor 7, and each i-th moving contact in this group is connected to (i + 1) -M normally closed contact contact 20.1 and with bus 15, contact

20 is connected to the bus 17.

In addition, the p-pair outputs of the bus switch unit 11 (bus 16, 17) are connected to the input of the measuring unit 24. In each circuit switching unit 21-23 there are inputs for connecting test and monitoring objects: in block 21 - inputs 25-27, in block 22 — inputs 28–30; in block 23 — inputs 31–33. Each input can be connected to one of the input buses using relay contacts (their windings are not shown). In block 21, relay contacts are designated 34–39, in block 22 — contacts 40–45, in block 23 — contacts 46–51. In addition, the device contains a threshold element 52.

The device works as follows

In the initial state, the buses 13, 15, 17, and 12, 14, 16 are connected together via the contacts 18-20 of the unit 11 and are connected to the unit 24. At the same time, the test voltage from the transformer 1 is not supplied to the switching blocks 21-23, and the switching units form an integrated unit with two input buses connected to the measuring unit 24, while the number of inputs for connecting the test object (control) of the combined unit is equal to the sum of the inputs of the incoming units

21-23. With this, it is possible to measure electrical parameters (e.g., resistance) between any two points in the range 25-33 using block 24.

Using the proposed device, the test of insulation strength is performed as follows. The object to be tested through connecting cables is connected to the inputs 25 - 33 blocks 21 volume: 18.2 with 19.2, 19.2 with 20.2 and, 23 switching circuits. In this case, the connectors of the unit have the first bus of the i-ro switching unit of circuits: contact 18.2 with width 12 of switching unit 21, 19.2 with bus 14 of switching unit 22, 20.2 with bus 16 of switching unit 23. The normally open contacts of the odd group are connected respectively to the terminals 8-10 of the section switching unit 5. Each i-th move: 1cny contact of this group is connected to (i + 1) -M normally closed contact and to the second bus of i-ro switching unit. Pin 18.1 is connected to pin 19.1 and to bus 13; pin 19.1 is connected to

50

55

The LIA, containing the leads to be tested by the highest voltage, is connected to the inputs 31-33 of the unit 23, the connectors with a lower voltage to the inputs 28 - 30 of the block 22, and the connectors with the leads that need to be tested with the lowest voltage, inputs 25 - 27 of block 21. The device is designed so that relative to pin 6 on pins 8-10 of block 5 of switching sections, the alternating test voltage is regulated by switching contacts 4.1 - 4.6 in such a range that on each of jogging 20.1 and with bus 15, contact

20 is connected to the bus 17.

In addition, the p-pair outputs of the bus switch unit 11 (bus 16, 17) are connected to the input of the measuring unit 24. In each circuit switching unit 21-23 there are inputs for connecting test and monitoring objects: in block 21 - inputs 25-27, in block 22 — inputs 28–30; in block 23 — inputs 31–33. Each input can be connected to one of the input buses using relay contacts (their windings are not shown). In block 21, relay contacts are designated 34–39, in block 22 — contacts 40–45, in block 23 — contacts 46–51. In addition, the device contains a threshold element 52.

The device works as follows

In the initial state, the buses 13, 15, 17, and 12, 14, 16 are connected together via the contacts 18-20 of the unit 11 and are connected to the unit 24. At the same time, the test voltage from the transformer 1 is not supplied to the switching blocks 21-23, and the switching units form an integrated unit with two input buses connected to the measuring unit 24, while the number of inputs for connecting the test object (control) of the combined unit is equal to the sum of the inputs of the incoming units

21-23. With this, it is possible to measure electrical parameters (e.g., resistance) between any two points in the range 25-33 using block 24.

Using the proposed device, the test of insulation strength is performed as follows. The object to be tested is via connecting cables that connect to the inputs 25 - 33 units 21 0

five

The LIA, containing the leads to be tested by the highest voltage, is connected to the inputs 31-33 of the unit 23, the connectors with a lower voltage to the inputs 28 - 30 of the block 22, and the connectors with the leads that need to be tested with the lowest voltage, inputs 25 - 27 of block 21. The device is designed so that relative to pin 6 on pins 8-10 of block 5 of switching sections, the alternating test voltage is regulated by switching contacts 4.1 - 4.6 in such a range that on each of you

Waters 8-10 voltage does not exceed the maximum allowable for this range.

In the initial state of the bus switching unit 11, when outputs 8-10 of block 5 are disconnected from the inputs of block 11, and the tires 16 and 17, which are connected via contacts 18-20, respectively, with buses 12, 1А and 13, 15, are connected block 24, monitors the correctness of the connections in the product over the entire field of contacts 25–33. Then they switch contacts 20.1, 20.2 to the position when pin 10 is connected to BUS 17) and common pin 6 through the primary winding of current sensor 7 to bus 16 Using contacts 4.1 - 4.6 of block 5, set the required voltage for the part of the product connected to switching locus 23, with the test voltage being monitored on buses 16 and 17 by means of unit 24.

Further, pins 46-51, those of the inputs 31 to 33, which are connected to the terminals of the product to be tested at the highest voltage, are connected to the buses 16 and 17 and are maintained for a normalized period of time under voltage. If the insulation breaks down, the current through the sensor 7 will increase the current more than the set Ig setpoint to the threshold element 52. The element 52 detects a disconnect signal that enters the unit 3 and disconnects the voltage from the inputs of the primary winding 2 of transformer 1. Testing the voltage is removed from tires 16 and 17, and

circuits of the product that were connected to the switching blocks of a lower voltage range, which increases the reliability of the device during testing. In addition, the use of switching units according to the number of test ranges After testing all the circuits under a voltage g, each of which calculated the test for the highest voltage for a given range, voltage, return 20.1 and 20.2 this, most of

to tires 16 and 17, classified as faulty, they are disconnected from the tires, connect the following, the test continues.

Pull back to the initial state, include contacts 19.1 and 19.2. At the same time, buses 15 and 17 are connected to terminal 9, and buses 14 and 16 through current sensor 7 are connected to terminal 6. With contacts 4. 4.4, block 5 exposes the required voltage for the part of the product connected to switching blocks 23 and 22 and control it with block 24.

Then pins 40-51 of those of inputs 28–33 that are connected to you

the product waters to be tested at a lower voltage are connected to the integrated tires 14, 16 and 15, 17 and kept for a normalized time under the test voltage. In the case of a sample, do so as in the tests in the previous range.

In the final stage, contacts 19.1, 19.2 return to the initial state, contacts 18.1, 18.2 connect pins 8, 6 to the first pair of buses 12, 13, and buses 14, 16 are also connected through normally closed contacts 19.1, 19.2, 20.1, 20.2. and 15, 17. Measure the test voltages with the help of block 24, if necessary regulate with pins 4.1 - 4.3. Then with pins 34-51 connect those of inputs 25-33 to the combined buses, which are connected to the terminals of the product to be tested at the lowest voltage Stand for a normalized time interval.

The conclusion from the health of the object is given in the same way as in previous tests.

The introduction of a bus switching unit with appropriate connections allows the switching units with a different range of test voltages to supply only test voltage permissible for a given unit, namely, a lower voltage can be applied to the entire set of switching units, while eliminating the high test voltage. marry

Claims (2)

1. A device for testing the electrical strength of the insulation, containing an alternating current voltage source to which the primary winding is connected through a disconnecting unit test voltage transformer, in series with WTO sections. The winding RFN11OI is connected to a current sensor connected to a threshold element, the output of which is connected to the control input of the disconnecting unit, a section switching unit, the outputs of which are connected to the leads of the secondary winding sections, the measuring unit different from that, in order to reduce the time spent on testing, circuit switching units were introduced into the device according to the number of test voltage ranges, the bus switch unit whose inputs are connected according to It is associated with the outputs of the section switching unit, and n pairs of outputs are connected respectively with the pa pairs of inputs bler, - and switching circuits, besides, n - a pair of outputs of the bus switching unit are connected respectively with two inputs of the measuring unit. 2. The device according to claim 1, about tl and - the fact that the bus switching unit contains n pairs of contacts forming the even and odd groups, and in the even group the i-th mobile contact is connected to the (1 + 1) -th normally closed a contact and a block output connected to the first input of the i-ro switching unit, and each normally open contact is connected to the primary winding of the current sensor in the odd-numbered group the i-th moving contact is connected to the (1 + 1) -th normally closed contact and with the output of the block associated with the second input of the i-ro circuit switching unit, and each but A normally open contact is connected respectively in the order of increasing numbers to the inputs of the block connected to the outputs of the switching unit of the sections in the order of increasing test voltage on them.