SU309320A1 - A METHOD FOR AUTOMATIC CONTROL OF NO - Google Patents

Description

The invention relates to methods for automatically monitoring the absence of a closure and insulation resistance on the case of busbars of DC sources by alternately connecting and disconnecting them to a sensitive control element, such as a current relay, using a switching unit with subsequent signaling and outputting information to the printing unit.

The known methods of control of a similar purpose do not exclude the effect of capacitive current from capacitors connected to the busbars to suppress interference in the DC source circuits and therefore do not provide the necessary accuracy of control.

In order to increase the control accuracy by eliminating the influence of capacitive current from the indicated capacitors, before each connection of the controlled bus to the sensitive element, it is closed to the case through a resistance equivalent to the resistance of the sensitive element.

FIG. 1 is a schematic diagram of an apparatus for carrying out the described method; in fig. 2-diagram of the register operation control circuits; in fig. 3 is a register and alarm circuit.

of output pulses of PSNP-RZ-PS relay, register P - relay Pb-PIS, sensitive element - PIS current relay, equivalent of a sensitive element - resistor Ri, device operation control elements - switch P, relay, PZI-PZS, button Kc, switching elements circuits of control, measurement, light and sound alarms and information output to the printing device - relay 24. 25-PSZ, RZZ, warning lights 1-Liu, bell Sv.

The drawing shows, by way of example, a device for carrying out the method as applied to the control of four DC sources Ui-Ui.

Automatic control is carried out as follows. The switch I set to position A is automatic. Through the contacts of the relay Pzi, Pi9 (see Fig. 2), voltage 27 is applied to the elements of the device. The multivibrator (Pi and Pr), the clock pulse generator "even," coup, (relay РЗ-PS) and the interrogation register (relay Re-RC) work. The contacts of the RT-Rtz relay interrogate the tires, i.e. alternate connecting to the device and disconnecting from it all monitored power supply buses. For the duration of the polling pulse, each tire is selected using a relay contact

measuring element valency - resistor Rt for 2-10 seconds for complete discharge or charging of existing capacitors between the current source buses and the housing, after which the resistor Ri is disconnected from the selected bus and connected to it via the PZ relay contacts - measuring element, relay coil Pie, the other end of which is connected to the housing. After switching off the winding of the relay RK from the selected bus, the PI relay is again triggered, the polling register connects to the device the next bus, which, like the previous one, and first closes through the resistor to the housing, and then connects to the relay Pie, etc.

If the bus to be monitored (opposite to the polarity of the monitored source relative to the bus connected to the relay Pie) is not closed to the housing and does not have the understood leakage resistance Ry and the current sufficient to operate the relay Pie, then its contacts remain open. If the controlled bus is closed to the case, or the leakage resistance is low and the current is sufficient to activate the Pie relay, then the Pie relay is triggered, and its contacts will receive a signal to the alarm elements: light - light "Body Liu, sound bell Sv, through the contacts of one of the relays, respectively, one of the Pas-Pcg relay is activated, which is blocked through its contacts, and one of the lights comes on, the corresponding one, and the bus closed to the housing, through the contacts of the PZZ-REE and RZZ relays, the information will go to the recording device .

For example, the bus "- | -I1 is closed on the body" - the light bulb lights up, the relay P2, PT, Pie is triggered. PZ, the “Liu's body” lamp lights up, and the bell rings for only for the duration of the closure of the PZ relay contacts. If there is a closure of several current sources on the busbar case, then the corresponding number of light bulbs will also be on. After the control of the last bus of the last source is completed, the register returns to its original state and the buses of the sources are polled again from the beginning. If the current source is disconnected from the current source with the bus closed to the case, then pressing the C button triggers the PZZ relay, the circuit breaks - 27 V, the corresponding relay P25-Pz2, which was blocked, unlocked and the corresponding lamp went out.

When controlling for a command from a printing device, the switch I is set to the position AP - “Automatic”. The seal. PIS relay triggers. From the printing device, a signal is sent to the device of the current source bus control — the L lamp lights, “Original press, the P2i relay is on. When issuing from the remote control system of any team to perform any operations, as well as receiving a receipt for the execution of a command in the controlled system, this information comes from the recording control panel to the printing device. At the moment of registration, the Le lamp goes out, the Print is original, and the relay P2z is turned on, i.e. a command is sent to the control device

current source busses.

In this case, through the contacts of the relay Pzi, PIS, PZS, voltage 27 is applied to the nodes of the device.

The operation of the device for monitoring the sources of current is carried out similarly to the operation of the device when the switch P is set to the initial position "Automatic. But in this case, the device will perform one cycle of monitoring all the current source buses and stop at the last device register level, the relay P24 will work. PIS, the multivibrator will stop working and, consequently, the process of polling current source busses to the next command from the printing device.

When checking the DC sources manually, the switch P is set to any of the following positions: 3, 5, 7, 9, 11, 13, 15, 17 (see Fig. 1) corresponding to the controlled tires -L, -HZ,, - Jaz,

+ Yaz, -Y4, + Ya4, while before installing the switch in the desired position, press the button Kn to close the selected bus to the case through the resistor Ri and through the contacts of the relay PI, and after 10 seconds release,

and the coil of the relay Pi6 is connected to the selected bus. In the case of the closure of a monitored tire (the opposite polarity relative to the selected tire of the monitored source), the Pie relay is activated on the case,

Liu's lamp is lit “Case, the bell rings.

Subject invention

The method of automatic control of the absence of closure and insulation resistance on the case of busbars of direct current sources by alternately connecting and disconnecting them to a sensitive control element, such as a current relay, using a switching unit with subsequent signaling and outputting information to the print unit, characterized in that in order to increase the control accuracy by eliminating the influence

capacitive current from capacitors connected between the tires of the current source and the case, before each connection of the controlled bus to the sensitive element, is closed to the case through the resistance,

equivalent to the resistance of the sensitive element.

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Poll register