RU2066867C1 - Device for test of protective set of high-harmonic filters - Google Patents

Abstract

FIELD: instruments for electric fault detection. SUBSTANCE: device provides automatic resume of device operations after their test when they are adversely affected in part. Locking circuits of output relays are divided into two groups. Test set is also divided into main and redundant. Device provides possibility to test when devices are partly switched off, to prohibit test when devices are switched off completely, to perform additional test when devices are switched on. Device provides dialog between automatic control system and control device. These goals are achieved by shift register with redundant number of outputs for initiation of protection, button for cycle skip, delay gates and differentiating circuits, as well as additional group of output relays and additional input for cycle skip register. EFFECT: increased functional capabilities. 1 dwg

Description

 The invention relates to electrical engineering, in particular, to relay protection and signaling and can be used for manual and automatic test control of a set of three-phase protection filters of higher harmonics and power capacitor banks to compensate for reactive power and suppress higher harmonics of DC power substations, large rolling drives mills, electric arc furnaces, static compensators, etc.

A device for test control of a set of three-phase protection against different types of damage, containing a test signal source, test control unit, test control start unit, tested protections, an output blocking element for trip and external alarm relays, and AND logic circuits [1]
The disadvantage of this device is the blocking of the output relays of all protections for the entire duration of the test control, and in case of partial failures in the protection, the output relays remain in a locked state until the intervention of maintenance personnel.

 Closest to the proposed and achieved result is a test control device [2] for a set of three-phase protection filters of higher harmonics, containing an automatic test control unit, the output of which is connected through the first input of the "OR" circuit to the input of the memory element, the first output of which connected to the input of the beginning of the test control of the shift register with an excessive number of outputs to start the protection and the button to skip the beat, the output of the end of the test control of the register move in! is connected to the reset input of the memory element; the second output of which is connected to the power supply circuit of the output protection relays, and the third to the local signaling element is “protection monitoring”, the second input of the “OR” circuit is intended to connect the manual start button of the test control. The outputs of the start of the protection of the shift register are connected to the inputs of the tested protections, and their outputs are connected respectively to the inputs of the "And" circuits, the number of which is equal to the number of protections and the number of protected objects, with the number of inputs of each "And" circuit equal to the number of outputs of the corresponding protection. The outputs of the circuits “And” are connected to the clock inputs of the shift register, and its output of the beginning of the test control is connected to the input of the time delay element, the output of which is connected to the local signaling element “Fault of protection” with the output to the ACS.

 The disadvantage of this device is: manual connection of functional protections in case of their partial failure, since the shift register stops in the position corresponding to the damaged protection, interruption of the testing process, lack of unlocking of output relays, warning and alarm signals in case of failure of one of the protections, long duration of the testing process determined by the backup time delays of 5-30 minutes, while the main protections work without time delays, the inability to use a known device for testing a set of filter protections, when the protected filters have several sets, each of which is equipped with an individual switch, there is no blocking for test control when the filter sets are completely disconnected, there is no separation of the malfunction according to the importance of protection, as main or backup protection, the possibility of test control when the filters are off and the lack of additional control after connecting the filters when the interval l the time of verification has expired, there is no collaboration between the control device and the automated control system, which ultimately reduces the reliability of protection.

 The purpose of the proposed device is to expand the functionality and increase the reliability of the protection kit by automatically putting them into operation after testing in case of partial damage, reducing the testing time of the main protections, by dividing the output relay blocking circuits into two groups and returning to normal operation after conducting their testing, and continuing testing of backup protections, ensuring the operation of the test control unit of the protection kit with partially off filters and prohibition of test control with all filters turned off and checking protection sensors by using the input signals of the sensors themselves during testing, dividing the type of fault alarm according to the importance of protection to primary and backup, additional test control after switching on the filter if it was turned off during the planned control, switching the automated control system to work in dialogue mode for the duration of the test control.

 This goal is achieved by the fact that in the test control device of a set of three-phase protection filters of higher harmonics, containing a block for automatically starting the test control, the output of which through the first input of the circuit "OR" is connected to the input of the start of the memory element, the first output of which is connected to the input of the beginning of the test control the shift register, the output of the end of the test control of the shift register is connected to the reset input of the memory element, the second output of the memory element is connected to the power circuit of the output relays it protects, and the third output of the memory element is connected to the local element of the alarm “protection control”, the second input of the “OR” circuit is used to connect the manual start button of the test control, the start output of the shift register protections is connected to the inputs of the tested protections, and the outputs of the tested protections are connected respectively to the inputs of the AND circuits, the number of which is equal to the number of protections and the number of protected objects and with the number of inputs of each And circuit equal to the number of outputs of the corresponding protection to which it is connected, and the outputs of the And circuits are connected to the clock the shift register, and the output of the beginning of the test control is connected to the input of the time delay element, the output of which is connected to the local element of the alarm "Fault protection" with an output to the ACS, an additional three-input circuit "And" is introduced into the start circuit, the first additional memory element with a start input, a reset input, and two outputs, a second additional memory element with a start input, a reset input, with an enable input, with an input for generating an additional test control signal and an output ala for additional test control, two additional time delay elements, an additional local alarm element "Failure of the main protection" with access to the automatic control system, logical elements "NOT" and differentiating chains in an amount equal to the number of protected objects having individual switches, three logical elements "OR" with the number of inputs equal to the number of protected objects having individual switches, the logical circuit "AND" with the number of inputs equal to the number of protected objects and an additional input test control ends, two-input logic circuits “AND” and an additional differentiating circuit of the local alarm reset circuit, two-input logic circuits “OR” in an amount equal to the number of protections and the number of protected objects, logical circuits “AND” in an amount equal to the number of protections and with the number of inputs of each circuits equal to the number of protected objects, an additional group of output relays of the main protections, an additional logic element "NO" in the circuit of the first additional memory element, a circuit for connecting contacts for position in switches of protected objects, an additional input of the “skip a beat” circuit of the shift register, one of the excess start outputs of the shift register protection is used to start the first additional memory elements and time delay, while the output of the start-up unit is connected to the input of the automated control system and to the first input of the three-input logic "I" circuit, the second input of which is connected to the output of an automated control system (ACS), and its output is connected to the first input of a two-input logic circuit "OR", one of the redundant Exit start protection register input connected to the first additional memory element and the entry of additional exposure time member whose output is connected to one of the clock inputs of the shift register; the start input of the first additional memory element and the start input of the second additional memory element are connected to the start input of the memory element, the second additional time delay element is connected to the output of the time delay element, and the output to the additional input "skip clock" shift register, additional local alarm Failure of the main protections "by the input connected to the two-input logic circuit" AND ", and by the output to the corresponding input to the ACS, the outputs of the elements" NOT "are connected to the first inputs of the two to the logical OR circuits and through the second OR logic element to the enable input of the second additional memory element, the outputs of the differentiating chains through the third OR logic element are connected to the input for generating the signal for additional test control of the second additional memory element, the output of the first logic circuit "OR" is connected to the second input of the additional logic circuit "AND"; the output of the logic circuit “And” is connected to the reset input of the second additional memory element, and the output of which signal for additional test control is connected to the start inputs of all three memory elements; the first output of the first additional memory element is connected to the power circuit of an additional group of output relays of the main protections; and its second output is connected to the first input of the two-input logic circuit "And" and through an additional element "NOT" is connected to the second input of the logic circuit "I", the output of which is connected to the input of the local signaling element "Fault of backup protection" with the output to the ACS; the input of the differentiating chain of the circuit reset the local alarm is connected to the input of the time delay element and the output of the beginning of the test control of the shift register; the second inputs of the OR circuits are connected to the outputs of the AND circuits, and their outputs are connected to the inputs of the logical AND circuits, the outputs of which are connected to the existing clock inputs of the shift register; the contact circuit of the position switch of the switches of the protected objects is connected to the inputs of the first logical circuit "OR", to the inputs of the elements "NOT", differentiating circuits and inputs of the logic circuit "I", to the additional input of which is connected the second output of the end of the test shift register; the first group of output relays is renamed to the backup protection output relays, and the local alarm element "Fault of protection" is renamed to "Fault of the backup protection".

The drawing shows a diagram of a device for monitoring three-phase protection filters of higher harmonics. The figure shows:
1 block of automatic start of test control,
2 two-input circuit "OR",
3 input start memory element 4,
5 output of memory element 4 (to shift register),
6 input start test control shift register 7,
7 shift register with an excessive number of protection start outputs and a clock skip button,
8 output end of the test control of the shift register 7,
9 input reset element 4,
10 second input of memory element 4 (to the relay),
11 output protection relays,
12 the third output of memory element 4 (to the alarm circuit),
13 element of the local alarm "control protection",
14 outputs start protection shift register 7,
15 tested protections,
16 of the "And" circuit in an amount equal to the number of tested protections and the number of protected objects and with the number of inputs of each equal to the number of outputs of each protection,
17 clock inputs of the shift register 7,
18 output beginning of the test control of the shift register 7,
19 time delay element
20 element of the local alarm "Fault protection",
21 three-input circuit "And",
22 the first additional memory element with a start input 23, a reset input 24 and two outputs 25, 26,
27 is a second additional memory element with start input 28, reset input 29, with enable input 30, with input 31 for generating an additional signal for additional test control and output 32,
33, 34 additional time delay elements,
35 additional element of the local alarm "Fault of basic protections",
36 logical elements "NOT",
37 differentiating chains,
38 three logical elements "OR" with the number of inputs equal to the number of protected objects,
39 logical circuit "And" with the number of inputs equal to the number of protected objects and an additional input end of the test control,
40, 41 two-input logic circuits "And",
42 additional differentiating circuit in circuit 43 reset local alarm,
44 two-input logic circuits "OR" in an amount equal to the number of protections and the number of protected objects,
45 logical circuits "And" in an amount equal to the number of protections with the number of inputs by the number of protected objects,
46 additional group of output relays of the main protections,
47 additional element "NOT",
48 circuit relay position switches of objects,
49 additional input "Skip a beat" shift register 7,
50 group of schemes "And" 16 in an amount equal to the number of protected objects,
51 group of schemes "And" 45 in an amount equal to the number of protections.

 The test control device of the set of protection for the higher harmonics filters contains a block (1) for automatically starting the test control, connected via the first input of the two-input OR circuit (2) to the start input (3) of the memory element (4), the first output of which (5) is connected to the input (6) of the beginning of the test control of the shift register (7) with an excessive number of protection start outputs (14) and a clock skip button. The output (8) of the end of the test cycle of the shift register is connected to the input (9) of the reset element (4) of the memory, the second output (10) of which is connected to the power supply circuit of the output relays (11) of the protection, and the third to the local signaling element (13) "protection control". The outputs (14) of starting the protection of the shift register (7) are connected to the inputs of the tested protections (15), and their outputs are connected respectively to the inputs of the AND circuits (16), the number of which is equal to the number of protections and the number of protected objects, with the number of inputs of each circuit "And" (16) equal to the number of outputs of the corresponding protection. The outputs of the AND circuits (16) are connected to the clock inputs (17) of the shift register (7), and its output (18) at the beginning of the test control is connected to the input of the time delay element (19), the output of which is connected to the local element (20) alarm "Fault protection" with access to the ACS. The device is equipped with an additional three-input logic circuit “AND” (21) with a first additional memory element (22) with a start input (23), a reset input (24), and two outputs (25, 26), a second additional memory element (27), with start input (28), reset input (29), with enable input (30), with input (31) for generating an additional test control signal and output (32), two additional time delay elements (33, 34), additional element ( 35) local alarm "Fault of the main protection" with the output to the ACS, logical elements ntami "NOT" (36) and differentiating chains (37) in an amount equal to the number of protected objects having individual switches, three logical elements "OR" (38) with the number of inputs equal to the number of protected objects having individual switches, logical circuit " And "(39) with the number of inputs equal to the number of protected objects, and an additional input for the end of test control, two-input I circuits (40, 41), as well as an additional differentiating circuit (42) for the local alarm reset circuit (43), two-input logic schemes " Lee "(44) equal in number to the number of protected objects logic" AND "(45) equal in number to the number of protection, and with the number of inputs of each circuit, equal to the number of protected objects, an additional group of output relays (46) of the main protection; an additional element "NOT" (47) at the output of the first additional memory element (22), a circuit (48) for connecting the relay contacts of the switches of protected objects; additional input (49) "skip a beat" of the shift register (7). One of the redundant protection start outputs (14) of the shift register is used to start the first additional memory elements (22) and time delay (33). In this case, the output of the start-up block (1) is connected to the input of the automated control system and to the first input of the three-input logic circuit (21), the second input of which is connected to the output of the automated control system (ACS), and its output is connected to the first input of the two-input logic circuit "OR "(2). One of the excess outputs of the protection start register (7) (14) is connected to the input (24) of the first additional memory element (22) and the input of the additional time delay element (33), the output of which is connected to one of those inputs (17) of the shift register ( 7). The start input (23) of the first additional memory element (22) and the start input (28) of the second additional memory element (27) are connected to the input (3) of the start of the memory element (4). The second additional time delay element (34) is connected by an input to the output of the time delay element (19), and by the output to the additional input (49) a “skip beat” of the shift register (7). An additional element (35) of the local alarm "Fault of the main protection" is connected to the two-input logic circuit "AND" (40) with an output to the input corresponding to the input to the ACS. The outputs of the elements “NOT” (36) are connected to the first inputs of the two-input logic circuits “OR” (44) and through the second logic element “OR” (38) to the enable input (30) of the second additional memory element (27). The outputs of the differentiating chains (37) through the third logical element "OR" (38) are connected to the input (31) of the formation of the signal for additional test control of the second additional memory element (27). The output of the first OR logic circuit (38) is connected to the third input of the additional AND logic circuit (21); the output of the AND circuit (39) is connected to the reset input (29) of the second additional memory element (27), and the output (32) of the signal for additional test control is connected to the inputs (3, 23, 28) of the start of all three memory elements (4, 22, 27). The first output (25) of the first additional memory element (27) is connected to the power circuit of an additional group of output relays (46) of the main protections, and its second output (26) is connected to the first input of the two-input logic circuit “I” (40) and through an additional element “NOT” (47) to the first input of the logic circuit “AND” (41), the output of which is connected to the input of the element (20) of the local alarm “Fault of backup protection” with an output to the ACS. The second inputs of the logic circuits “AND” (40, 41) are connected to the output of the time delay element (19). The input of the differentiating chain (42) of the local alarm reset circuit (43) is connected to the input of the time delay element (19) and the output (18) of the beginning of the test control of the shift register (7). The second inputs of the OR circuits (44) are connected to the outputs of the AND circuits (16), and the outputs of the OR circuits (44) are connected to the inputs of the logical AND circuits (45), the outputs of which are connected to the corresponding inputs (17) shift register (7). The circuit (48) of contacts of the relay of the position of the circuit breakers of the protected objects is connected to the inputs of the first logical circuit "OR" (38), to the inputs of the elements "NOT" (36), differentiating circuits (37) and the inputs of the logical circuit "AND" (39), the additional input of which is connected to the second output (8) of the end of the test control of the shift register (7). The group of output relays (11) is renamed to the output relays of the backup protection, and the element (20) of the local alarm "Fault of protection" is renamed to "Fault of the backup protection".

 The device operates as follows.

 In the automatic test control start block, an internal, independent and adjustable time delay is triggered. If there is at least one connected protected object on one of the circuits 48, there is a signal that passes through the corresponding input of the OR circuit (38) to the first input of the three-input circuit And (21). The signal from the start block (1) is fed to the second input of the And circuit (21) and the input of the automated control system (ACS), which receives this signal as an initiative signal, switches to work in a dialogue mode with the currently controlled object and generates a ready signal , which is fed to the third input of the AND circuit (21) and allows the signal to pass from the internal time delay of the start block (1) to the output of the AND circuit (21) and through the OR element (2) to the memory input triggers ( 4, 22, 27). Moreover, the memory element (27) is launched only if there is at least one disconnected object by signals in the circuit (48), through the elements "NOT" (36) and the circuit "OR" (38) at the enable input (30).

 The main element (4) of the memory at the output (10) generates a blocking signal for the group of output relays (11) of the backup protection, at the output (12) it generates a signal for the element (13) of the local signaling "Protection monitoring" and at the output (5) a signal that fed to the input (6) of the shift register (7) and sets it to the test control mode.

 The shift register 7 generates a signal to prepare for the start of the first tested protection at the corresponding output (14), and at the output (18) it generates a start signal for the time delay element (19), the response time of which is set longer than the test control time for all protections. Since the protections are divided into two groups: the main and backup tests start with the main protections and after verification they are returned to normal operation and continue to check the backup protections.

 Consider the operation of the device in the control of serviceable protections.

 Under the action of one of the signals at the output 14 of the block 7 of the shift register, the corresponding main protection is triggered and at its output signals are generated, for example, the type of protection, stage numbers, phase numbers, object number (object type). When the protection is activated, the object does not turn off, since the power of the output relays is blocked. The protection operation signals are fed to the inputs of the corresponding AND circuit 16, at the output of which a logical unit is formed, since it considers operation with serviceable protections. If artificial signals are used during testing, then at the output of all "I" circuits (16) of all objects (50) corresponding to one type of protection, logical unit signals are generated, which are fed through the "OR" circuits to the corresponding "And" circuits (45) and from its output to one of the clock inputs (17) of the shift register 7, setting it to check the next protection. If during testing they use signals from sensors of protected objects by increasing the amplification factors to the level of protection operation, then at the outputs of the protection of objects that are disabled, there will be no signals and, accordingly, the output signal in the corresponding circuit "I" (16). And also, provided that the device is constructed in such a way that one type of protection is simultaneously tested for all protected objects, the signal at the output of the “AND” circuit corresponding to this object (16) is replaced by the signal from the output of the corresponding “NOT” circuit (36) at the first input of the circuit OR (44).

 After checking the last protection from the group of basic protections, the shift register is set to a position in which instead of checking the next protection with a signal from one of the excess start outputs (14) of the register (7), the first additional time delay element (33) is triggered and through the input (24) the first additional memory element is triggered (22). At the outputs (26, 25) of the element (22), signals are taken, after which the power of the group of output relays (46) of the main protections is restored, that is, the main protections return to normal operation. Thus, during further verification of backup protection in the event of damage to the elements in the protected object, it becomes possible emergency shutdown of the damaged object. After the first additional delay element (33) is activated, a signal is generated at its output, which is fed to one of the clock inputs (17) of register 7 and sets it to the position for monitoring the first backup protection. After the last backup protection, a signal is generated at the last output of the shift register 7, which is used as the end of the test control and, through the output (8), is fed to the reset input (9) of the main memory element (4) and returns to its original state, in which the output (10) removes the blockage from the power supply circuit of the backup protection relay group and through the output (12) the signal is removed from the output of the local alarm element "Protection monitoring 13". Upon completion of the verification of each protection at the output (18) of the register (7), a reset signal is generated for the time delay element (19) and through an additional differentiating chain (42) of the local alarm reset circuit (43). The signal of the end of the test control from the output (8) of the register (7) is fed to the additional input of the logic circuit “I” (39) and, if there are signals about the connected state of all protected objects, a reset signal is generated at the output of the circuit (39), which is fed to the input (28) the second additional memory element (27) and resets it.

 If there is at least one disconnected object, the output of the And circuit (39) does not have a reset signal at the input (28) of the memory element (27), and thereby information about the test control in the presence of the disconnection of the object is saved. When connecting a protected object, the control of which has not been carried out, an additional signal is automatically generated to conduct additional test control. The specified signal is generated as follows. When a signal is changed from logical zero to a logical unit in one of the circuits (48) when another object is connected, the signal is differentiated using the corresponding chain (37) and through the third logical element “OR” (38) is fed to the input (31) of the second additional memory element (27), at the output (32) of which a start signal of all memory elements is generated and test control resumes.

 Consider the operation of the device when damage is detected in the protections.

 For example, when testing one of the protections of the main protection group, a malfunction is detected, that is, one or more signals from the set of a certain protection are missing. At the output of the corresponding AND circuit (16), there will be no signal and, accordingly, the signal at the output of the And system (45) and at the corresponding input (17) of the shift register (7), the shift register (7) stops in the position corresponding to the faulty protection . This situation persists until the main element (19) of the time delay is triggered, which starts when the test starts, the signal from the output of which is fed to the second inputs of the logic circuits “I” (41 and 40). When testing the main protection group, at the output (26) of the memory element (22) there is a signal that is fed to the first input of the AND circuit (40), the output of which is fed to the input of the local signaling element (35) of the main protection malfunction and (35) turns on the indicated alarm. In addition, the signal from the output of the exposure element (19) enters the input of the second additional time delay element (34) and, after its operation, a signal is supplied to the additional input (49) of the “skip beat” of shift register 7 and sets the latter to the next position, i.e. e. to check the next protection. Element (34) is necessary for triggering an alarm about a fault in the protection of which these relays can be included.

 When checking backup protection and detecting faulty protection, the shift register (7) similarly stops, the time delay element (19) is triggered, and a signal is sent to the element inputs (41, 40, 34). When checking backup protection, the first additional memory element (22) is in a reset state and, accordingly, there is no signal at the output (26), whose logic zero is fed through the "NOT" element (47) to the first input of the "AND" circuit (41) and allows passage signal element (19) to the input element (20) of the local alarm "Fault backup protection" and includes the specified alarm. Similarly, the second additional time delay element (34) is triggered and supplies a signal to the additional input (49) “skip a beat” of shift register 7 and sets the latter to the next position. The signal of the element (34) imitates the signal from the output of the next protection. After completion of the test control, regardless of whether the defenses are fully operational or partially defective, the output relays are disabled and the protections are switched to normal operation with the output of signals about the test control and its results.

Claims (1)

 A test control device for a set of protections for higher harmonics filters, containing an automatic test control start block, connected to the first input of the first OR element by an output, connected to the main memory element connected to the start input, the first output of which is connected to the input of the test control shift shift with an excessive number of outputs start protection and a button to skip a beat, the output of the end of the test test connected to the reset input of the main memory element, the second output it is connected to the power circuit of the output protection relays, and the third output to the local element of the alarm is “Protection Protection”, the start outputs of the shift register protections are connected to the corresponding inputs of the tested protections, the outputs of which are connected respectively to the inputs of the first AND elements, the number of which is equal to the number of protections and the number protected objects, with the number of inputs of each AND element equal to the number of outputs of the corresponding protection, the outputs of the first AND elements are associated with the clock inputs of the shift register, the output of the beginning of the test control is connected to the input of the main time delay element, the output of which is connected to the input of the local alarm element "Failure of backup protection", which has an output to the automated control system, characterized in that an additional element And, the first additional memory element with a start input, a reset input and two outputs, a second additional memory element with a start input, a reset input, an enable input, an input for generating an additional test control signal and an output, two will complement time delay elements, an additional local alarm element "Fault of the main protection", having access to the automated control system, the first elements NOT and the first differentiating chains in an amount equal to the number of protected objects, having individual switches, three OR elements with the number of inputs equal to the number protected objects having individual switches, the second additional element And with the number of inputs equal to the number of protected objects, and an additional input end test counter Oli, two two-input AND elements, a second differentiating chain of the local alarm reset circuit, additional two-input OR elements in an amount equal to the number of protections and the number of protected objects, third additional And elements in an amount equal to the number of protections, and with the number of inputs of each circuit equal to the number protected objects, an additional group of output relays of the main protection, the second element is NOT, the connection circuit of the relay contacts of the switches, protected objects, while the output of the start-up unit is connected to the output of the automatic control system and is connected to the first input of the first two-input element OR through the first input of the three-input element AND, the second input of which is connected to the output of the automated control system, one of the excess outputs of the start of the shift register protection is connected to the reset input of the first additional memory element and the input of the first additional element time delay, the output of which is connected to one of the clock inputs of the shift register, the start outputs of the first and second additional memory elements are connected to the start input of the main memory element, the second additional time delay element is connected by an input to the output of the first time delay element, and by the output to the additional input "Skip clock" of the shift register, an additional local alarm element, "Fault of the main protection" is connected to the output of the first two-input element And, and by accessing the corresponding input to the automated control system, the outputs of the first elements are NOT connected to the first inputs of the additional two-input elements OR and through the second OR element to the enable input of the second additional memory element, the outputs of the first differentiating chains through the third OR element are connected to the input of the signal for additional test control of the second additional memory element, the output of the first OR element is connected to the third input of the additional three-input element AND, the output of the second additional element AND connected to the reset input of the second additional memory element, the signal output for additional test control which is connected to the start inputs of the main and additional all memory elements, the first output of the first additional memory element is connected to the power circuit of an additional group of output relays of the main protection, and its second output to the first input of the first two-input element And through the second element NOT to the first input of the second two-input element And, through the second input of which the output of the main time delay element is connected to the input of the local alarm element "Fault of backup protection", the second input of the first two-input element And is connected to the output of the main element of the time delay, the input of the second differentiating chain of the local alarm reset circuit is connected to the input of the main element of the time delay and the output of the start of the test control of the shift register, the outputs of the first elements And are connected with the corresponding clock inputs, shift registers through the second additional two-input codes OR elements and third additional AND elements, inputs of the first OR element, inputs of the first NOT elements, first differentiating chains and inputs of the second additional the element And are connected to the circuit of the relay contacts of the position switches of the protected objects, and the additional input of the second additional element And is connected to the second output of the end of the test control of the shift register.