RU128757U1 - CONTROL SYSTEM OF DISCRETE SIGNAL SOURCES - Google Patents

Abstract

1. A system for monitoring the state of discrete signal sources, containing a discrete sensor connected by one output to a pulse source consisting of a power source, a transistor switch and a pulse generator, and the other output to the beginning of a communication line, at the other end of which an object control device input is connected through a driver control, characterized in that it entered the control unit of the communication line containing a key, the first input of which is connected to the second output of the power source as part of the pulse source, and in the key output is connected to a communication line wire connected to a discrete sensor, to the second wire of which a current sensor is connected, the output of which is connected through an amplifier with a delay element through one of the inputs of the “OR” element to the input of the trigger to “zero”, to the second input of the element “OR” the “Reset” button is connected, one of the outputs of the pulse generator is connected to the input of the trigger setting to “one”, it is also connected to the second input of the key of the control unit of the communication line, and the output of the trigger is connected to an RC circuit, the output of which is connected n the input of the threshold element, the output of which is connected to the status indicator of the communication line. 2. The system according to claim 1, characterized in that the key of the control unit of the communication line is connected with the possibility of closing in time intervals corresponding to the open state of the transistor switch of the pulse source connected to the discrete sensor.

Description

The utility model relates to the field of automatic control of technological equipment, including remote control, and information-measuring equipment, and in particular, devices for generating and transmitting electrical signals in pulsed form and can be used to monitor the status of discrete signal sources (for example, sensors , buttons, switches) in control systems of technological equipment complexes, for example, automatic lines, and information-measuring systems.

In these areas of technology there is a need to obtain information about the progress of a controlled technological process using discrete contact sensors, the closed or open state of which is determined by the technological contact sensor or button, and on the other hand, a control device for forming the process.

This information is transmitted via a communication line to which a contact sensor or button is connected on one side and a control device for generating equipment control commands on the other.

As a prototype, a device for monitoring the state of discrete signal sources can be adopted (RF patent for utility model No. 53048, G08C 19/18, Н02М 3/335, publ. 04/27/2006.), Containing a communication line, at one end of which a discrete contact is connected sensor, on the other - through the driver, the input of the control device, characterized in that a pulse source is inserted into the device, the output of which is connected to one of the outputs of the discrete sensor, the other output of which is connected to the communication line, to the other end of which a divider of two been consistent connected resistors to the output of which is connected a diode amplitude detector input filter, the output of which is connected to the input of the control device for forming control commands. The pulse source includes a pulse generator, a power source, a transistor switch.

The disadvantages of the prototype include the lack of control of the state of the line along which information is transmitted about the state of the discrete sensor, which reduces the reliability of information transfer. This disadvantage is eliminated by the proposed solution.

The task at hand is the expansion of the system’s functionality.

The technical result consists in the fact that, in addition to the state of the discrete signal source, the state of the communication line is constantly monitored, which ensures:

- improving the reliability of discrete signal sources and the reliability of determining their condition;

- automatic continuous monitoring of a break in the communication line;

- instant detection of the fact of a line break and minimization, thereby, the time to eliminate it;

- improving the reliability of determining the state of a discrete signal source by eliminating the incorrect perception of its state associated with a broken line, which allows you to separate the failures of a discrete signal source and line.

This is achieved by the fact that in the state monitoring system of discrete signal sources containing a discrete sensor connected by one output to a pulse source, consisting of a power source, a transistor switch and a pulse generator, the other output to the beginning of the communication line, at the other end of which an input is connected control device of the control object, a communication line monitoring unit is introduced containing a key, the first input of which is connected to the second output of the power source as part of the pulse source, and the output the key is connected to a communication line wire connected to a discrete sensor, to the second wire of which a current sensor is connected, the output of which is connected through an amplifier with a delay element through one of the inputs of the "OR" element to the input of the trigger to "zero", to the second input of the element OR ”the“ Reset ”button is connected, one of the outputs of the pulse generator is connected to the input of setting the trigger to“ one ”, it is also connected to the second input of the key of the control unit of the communication line, and the output of the trigger is connected to an RC circuit, the output of which is connected to One of the threshold element to the output of which the line status indicator is connected. Moreover, the key of the line monitoring unit is connected with the possibility of closing in time intervals corresponding to the open state of the key of the pulse source connected to the discrete sensor.

Figure 1 shows a schematic diagram of a system; 2 is a timing chart for illustrating operation.

The system contains a pulse source 1 with outputs 1 and 2, a discrete sensor 2, the state of which is determined by the technological process or an operator’s command, a communication line 3, a shaper 4 which includes a divider on resistors R1 and R2, to the output of which a control device 5 of the control object, for generating control commands, a wire 6 connecting the discrete sensor on one side with the transistor switch 7 of the pulse source, which also includes a direct current power supply IPPT and a generator p pulses 8 GI, and on the other hand, with the input of communication line 3 (first straight wire L1.1-L1.2) These elements are present in the prototype — RF patent for utility model No. 53048. A communication line monitoring unit has been introduced into the system, containing in the second return wire of communication line 3 (L2.1-L2.2) a current sensor 9 in the form of a resistor R _w connected to an amplifier 10, the output of which through the delay element 11 is connected to the first input of the element 12 “OR”, the output of which is connected to the input “R” of setting to “zero” of trigger 13. The reset button is connected to the second input of element 12 “OR”. Output 2 of pulse generator 8 (as part of pulse source 1) is connected to input “S” of setting trigger 13 to “unity”, also connected to second input of key 14 of communication line control unit, first input of which is connected to second output with voltage Uout. 2 IPPT as part of the pulse source 1, and the output of the key 14 is connected to the first wire (L1.1) of the communication line 3. The output of the trigger 13 is connected to the RC circuit 15 with the diode VD1, to the output of which (capacitor C) is connected the input of the threshold element 16, for example, in the form of a Schmitt trigger, to the output of which an indicator is connected Status line 17, in the form of a LED VD2 resistor R. To register output line failure threshold element 16 may be connected to a computer. Elements of the circuit 9-17 are included in the control unit of the communication line. The key 14 of the control unit of the communication line is connected with the possibility of closing in time intervals corresponding to the open state of the transistor switch 7 of the pulse source 1 connected to the discrete sensor 2.

The system operates as follows (Figure 2).

The pulses at the input of the discrete sensor 2 are generated from the IPPT with a voltage U _out .1, as part of the pulse source 1, when the transistor switch 7 is closed, which is controlled by pulses from the output 1 of the pulse generator 8. When the discrete sensor 2 is closed, these pulses enter the line communication 3 (Figure 2, a) and then after processing by the shaper 4 enter the control device 5 of the control object. In accordance with the prototype, these pulses are characterized by high duty cycle, i.e. the condition that

t _and << T _and ,

where t _and is the pulse duration,

T _and - the pulse repetition period.

To monitor the condition of the line, the transistor switch 14 provides the supply to the beginning of the communication line of pulses (Figure 2, b), from the second output of the IPPT pulse source 1. with a lower voltage U _o .2.

The voltage U _o .2 is selected so that the pulses for checking the line do not lead to the formation of control commands for the control device 5. This is achieved so that the voltage U _{d of the} output of the divider R1, R2 of the shaper 4 is less than the input voltage of the control device 5, corresponding to the level of the logical unit U _log..ed. .

or

If we accept that these conditions are met with a margin, then

Key 14 is controlled by pulses from output 2 of the pulse generator ГИ 8, which follow with the same period T _and duration t _and , but are shifted (delayed) relative to the pulses from the output 1 of ГИ for the time t ₃ 1 (Figure 2, b ) Thus, the supply to the line of pulses with an amplitude U _o .2 occurs in the intervals between the main pulses with an amplitude U _o .1.

We call the main first pulses with an amplitude U _o .1 as impulses for monitoring the CD sensor, and the impulses with an amplitude U _oo. 2 as impulses for monitoring the communication line of the CL. To control the passage of CL pulses along the communication line, a current sensor 9 is included in its second wire L2.1 - L2.2 in the form of a shunt resistance R _w . In the normal state line and the key circuit 14 passes current through the circuit U _O .2 IPPT, the key 14, the first conductive line L1.1 - L1.2, divider resistors R1, R2 in the composition of the shaper 4, the second conductive line L2.2 - A2 .1, current sensor 9, common wire (⊥) IPPT.

The pulses from the output 2 ГИ 8 control the closure of the key 14 and simultaneously arrive at the input "S" of the installation in the trigger unit 13, which is shown in Figure 2, d. With the passage of current along the line due to the action of CL pulses, a pulse signal DT is generated on the current sensor 9 (Figure 2, c), which through the amplifier 10, a delay element 11, which biases it by the time t ₃ 2 (Figure 2, g) and the element "OR" 12 is fed to the input "R" of the trigger 13 and puts it in its original state. At its output, a voltage is set corresponding to the level of logical zero. This process corresponds to the normal (normal) state of the communication line (Figure 2, e).

An RC chain is connected to the output of the trigger 13, therefore, in the single state of the trigger 13, the capacitor C starts to charge, but due to the short-term single state of the trigger 13, the voltage across the capacitor C does not have time to reach the value of the threshold setting of the threshold element 16, as a result of which a level will be present at its output logical zero. At the same time, the VD2 LED does not light up, which indicates the normal state of the communication line.

In the event of a breakdown of any wire of the line, when KL pulses arrive at the input of the L1.1 line (Figure 2, b), there will be no response signal from the current sensor 9, as a result of which the trigger 13, delivered to the unit by the pulse from the output. 2 GI, will not be reset (Figure 2, e, "Open"). In this case, the capacitor C (RC circuit 15) is charged to the threshold level U _threshold . (Figure 2, g), which leads to the switching of the threshold element 16 to a single state (Figure 2, h) and the LED VD2 of the line status indicator 17 signaling a broken line.

A single signal from the output of the threshold element 16 can also be fed to a computer to register a break in the communication line and take measures to eliminate it. After eliminating the breakage of the communication line, the "Reset" button must be pressed to bring the control unit of the communication line to its original state (Figure 2, and). The diode VD1 in the RC circuit 15 provides a fast discharge of the capacitor C when the trigger 13 is switched from a single state to zero.

Claims (2)

1. A system for monitoring the state of discrete signal sources, containing a discrete sensor connected by one output to a pulse source consisting of a power source, a transistor switch and a pulse generator, and the other output to the beginning of a communication line, at the other end of which an object control device input is connected through a driver control, characterized in that it entered the control unit of the communication line containing a key, the first input of which is connected to the second output of the power source as part of the pulse source, and in the key output is connected to a communication line wire connected to a discrete sensor, to the second wire of which a current sensor is connected, the output of which is connected through an amplifier with a delay element through one of the inputs of the “OR” element to the input of the trigger to “zero”, to the second input of the element “OR” the “Reset” button is connected, one of the outputs of the pulse generator is connected to the input of the trigger setting to “one”, it is also connected to the second input of the key of the control unit of the communication line, and the output of the trigger is connected to an RC circuit, the output of which is connected n the input of the threshold element, the output of which is connected to the status indicator of the communication line. 2. The system according to claim 1, characterized in that the key of the control unit of the communication line is connected with the possibility of closing in time intervals corresponding to the open state of the transistor switch of the pulse source connected to the discrete sensor.

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