CN112054497A - Communication equipment switching value output type explosion-proof safety barrier - Google Patents

Communication equipment switching value output type explosion-proof safety barrier Download PDF

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Publication number
CN112054497A
CN112054497A CN202010983950.6A CN202010983950A CN112054497A CN 112054497 A CN112054497 A CN 112054497A CN 202010983950 A CN202010983950 A CN 202010983950A CN 112054497 A CN112054497 A CN 112054497A
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CN
China
Prior art keywords
electrically connected
resistor
pin
terminal
power supply
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010983950.6A
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Chinese (zh)
Inventor
李威
周虎
侯荣奇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Suzhou Beijiafu Electric Automation Co ltd
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Suzhou Beijiafu Electric Automation Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Application filed by Suzhou Beijiafu Electric Automation Co ltd filed Critical Suzhou Beijiafu Electric Automation Co ltd
Priority to CN202010983950.6A priority Critical patent/CN112054497A/en
Publication of CN112054497A publication Critical patent/CN112054497A/en
Pending legal-status Critical Current

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D3/00—Arrangements for supervising or controlling working operations
    • F17D3/01—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of a product
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
    • G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
    • G05B19/0423—Input/output
    • G05B19/0425—Safety, monitoring
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
    • H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/02—Constructional details
    • H04Q1/11—Protection against environment
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/20—Pc systems
    • G05B2219/21—Pc I-O input output
    • G05B2219/21126—Signal processing, filter input

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

The explosion-proof safety barrier can limit the energy of switching value equipment, and at the same time can make explosion-proof treatment, and can limit the energy on the data line when the switching value signal is transferred into dangerous site, so that it is not enough to ignite explosive mixture, and at the same time can electrically isolate two equipments so as to raise the anti-interference property and safety of industrial control network. For example, if the electromagnetic valve is electrically connected to a non-explosion natural gas on-off controller, reliable communication guarantee can be realized by adding the electromagnetic valve provided by the invention, switching value signals of the controller are transmitted to field equipment and simultaneously subjected to explosion-proof treatment, any switching value signal in the controller is transmitted to the field, the energy on a line is not enough to ignite explosive mixtures, and meanwhile, the two equipment are electrically isolated, so that the safety and the reliability of industrial control are enhanced.

Description

Communication equipment switching value output type explosion-proof safety barrier
Technical Field
The invention relates to a signal isolation safety device, in particular to a switching value output type explosion-proof safety barrier of communication equipment, which can perform voltage limiting and current limiting energy control and electrical isolation on a switching value control circuit when a controller sends a downlink control instruction between field execution mechanisms, ensures the reliability of the transmission circuit in an automatic control occasion with explosive factors, realizes automatic control and remote operation, and can ensure signal isolation transmission and explosion-proof processing.
Background
With the continuous improvement of the industrial automation degree, the application of automatic control is higher and higher, and the downlink control instruction of the controller is indispensable for controlling the on-off of the field device. However, when an explosive factor exists, the electric arc can be caused by directly powering off the equipment, and the ignition caused by overlarge current can occur when the equipment is directly powered on, so that the situation is not allowed in an explosive environment, and the safety of life and property cannot be guaranteed. Ordinary switching value signals can not be directly used in places with explosive dangers, for example, in the fields of coal, petrochemical industry, natural gas and the like, when the switching value signals are switched on and off in the fields, lines are struck, explosive combustible materials are ignited, and the dangers are extremely high.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a switching value output type explosion-proof safety barrier of communication equipment, which can perform voltage limiting and current limiting energy control and electrical isolation on a switching value control circuit when a controller sends a downlink control instruction between field execution mechanisms, ensures the reliability of a transmission line in an automatic control situation with explosive factors, realizes automatic control and remote operation, and can ensure signal isolation transmission and explosion-proof processing.
The technical scheme adopted by the invention for solving the technical problems is as follows: a switching value output type explosion-proof safety barrier of communication equipment comprises an input end power supply management circuit, a transformer output rectifying filter circuit and an explosion-proof processing circuit of an intrinsic safety end, wherein the input end power supply management circuit consists of a pulse width modulation chip U3, a transformer U1, an input terminal U2C and an on-off signal indicator lamp D8, the input terminal U2C transmits signals to a pulse width modulation chip U3, the pulse width modulation chip U3 controls a primary side coil of the transformer U1, the transformer U1 feeds back coil feedback signals to a pulse width modulation chip U3, the voltage stabilizing function can be achieved, the transformer output rectifying filter circuit outputs signals to the rectifying filter circuit through a secondary side coil of the transformer U1, the signals are rectified and filtered and then transmitted to the explosion-proof processing circuit of the intrinsic safety end, and then the signals are output through an output terminal U2A.
The invention has the advantages that the invention can provide the switching value output type explosion-proof safety barrier of the communication equipment, can limit the energy of the switching value equipment, simultaneously carry out explosion-proof treatment, limit the energy on a data line when a switching value signal is transmitted to a dangerous site, ensure that the energy is not enough to ignite explosive mixtures, simultaneously electrically isolate the two equipment, and enhance the anti-interference performance and the safety of an industrial control network. For example, if the electromagnetic valve is electrically connected to a non-explosion natural gas on-off controller, reliable communication guarantee can be realized by adding the electromagnetic valve provided by the invention, switching value signals of the controller are transmitted to field equipment and simultaneously subjected to explosion-proof treatment, any switching value signal in the controller is transmitted to the field, the energy on a line is not enough to ignite explosive mixtures, and meanwhile, the two equipment are electrically isolated, so that the safety and the reliability of industrial control are enhanced.
Drawings
The structure and characteristics of the switching value output type explosion-proof safety barrier for communication equipment according to the present invention will be further described with reference to the accompanying drawings and embodiments, wherein:
fig. 1 is a circuit diagram of a first embodiment of the present invention.
Fig. 2 is a block circuit schematic diagram of a first embodiment of the present invention.
In the figure: u1. transformer, U3. pulse width modulation chip, U2C input terminal, U2A output terminal, D8. on-off signal indicator lamp, Q1. reference source and Q2 field effect transistor.
Detailed Description
In the embodiment shown in fig. 1, a transformer (U1), a pulse width modulation chip (U3), an input terminal (U2C), an output terminal (U2A), an on-off signal indicator lamp (D8), a reference source (Q1) and a field effect transistor (Q2) are provided.
In the embodiment shown in fig. 2, the circuit principle of the present invention is labeled as follows: the safety side switching value signal is input into the power supply management circuit, the signal adjusted by the power supply management circuit is input into the pulse width modulation chip, the signal is isolated by the pulse width modulation chip and the high-frequency transformer, rectified and filtered, and then input into the explosion-proof processing circuit, and the signal can be connected to the dangerous side switching value signal after explosion-proof processing, so that the safety purpose is achieved.
The invention relates to a communication equipment switching value output type explosion-proof safety barrier, which comprises an input end power supply management circuit, a transformer output rectifying and filtering circuit and an explosion-proof processing circuit at an intrinsic safety end, wherein the input end power supply management circuit is composed of a pulse width modulation chip (U3), the transformer (U1), input terminal (U2C) and break-make signal indicator lamp (D8) are constituteed, input terminal (U2C) signal transmission is to pulse width modulation chip (U3), pulse width modulation chip (U3) control transformer (U1) primary coil, transformer (U1) feedback coil feedback signal gives pulse width modulation chip (U3), can realize the function of stabilizing voltage, transformer output rectifier filter circuit is given rectifier filter circuit by transformer (U1) secondary winding output signal, the signal is given the explosion-proof processing circuit of this ampere's end after rectifier filter, then export via output terminal (U2A).
According to the communication equipment switching value output type explosion-proof safety grid, the 6 th pin of an input terminal (U2C) is electrically connected with the negative pole GND of a non-intrinsic safety end power supply, the 5 th pin of the input terminal (U2C) is electrically connected with a capacitor (C5) and a fuse (F2), the other end of the capacitor (C5) is electrically connected with the negative pole GND of the non-intrinsic safety end power supply, the other end of the fuse (F2) is electrically connected with the positive pole of a diode (Q3), the negative pole of the diode (Q3) is electrically connected with the positive pole of an electrolytic capacitor (C7), a resistor (R10), the collector of a triode (Q4), a resistor (R7) and the 12 th pin of a transformer (U1) and the positive pole VCC of the non-intrinsic safety end power supply, the negative pole of the electrolytic capacitor (C7) is electrically connected with the negative pole GND of the non-intrinsic safety end power supply, the other end of the resistor (R10) is electrically connected with the base of the triode (Q4) and the negative pole of the diode (D7), the positive pole of the diode (D7) is electrically connected The power supply circuit comprises a 7-pin VCC, a negative electrode end of a capacitor (C9) is electrically connected with a negative electrode GND of a non-intrinsic safety end power supply, the other end of a resistor (R7) is electrically connected with a resistor (R9) and a 6 th pin UV of a pulse width modulation chip (U3), the other end of a resistor (R9) is electrically connected with a resistor (R13) and a 5 th pin OV of the pulse width modulation chip (U3), the other end of a resistor (R13) is electrically connected with a negative electrode GND of the non-intrinsic safety end power supply, and the 8 th pin VD of the pulse width modulation chip (U3) is electrically connected with a 11.
In the communication equipment switching value output type explosion-proof safety barrier, a 4 th pin CMP of a pulse width modulation chip (U3) is electrically connected with a resistor (R12) and a capacitor (C6), the other end of the resistor (R12) is electrically connected with a capacitor (C8), the other end of the capacitor (C8) is electrically connected with the other end of a capacitor (C6), a resistor (R8), a resistor (R11) and a 3 rd pin FB of the pulse width modulation chip (U3), a 2 nd pin CT of the pulse width modulation chip (U3) is electrically connected with a capacitor (C4), the other end of the capacitor (C4) is electrically connected with a capacitor (C3), a 1 st pin GND and a non-intrinsic safety end power supply cathode GND of the pulse width modulation chip (U3), a 10 th pin of a transformer (U1) is electrically connected with the non-intrinsic safety end power supply cathode GND, a 9 th pin of the transformer (U1) is electrically connected with a diode (D2), the cathode end of the diode (D2) is electrically connected with the other end of the, the other end of the resistor (R11) is electrically connected with the negative pole GND of the non-intrinsic safety end power supply.
The invention relates to a switching value output type explosion-proof safety grid of communication equipment, wherein a 1 st pin of a transformer (U1) is electrically connected with a positive terminal of a diode (D1), a negative terminal of the diode (D1) is electrically connected with a positive terminal of an electrolytic capacitor (C1), a capacitor (C2), a resistor (R5), a fuse (F1) and a positive terminal VO of a local-safety-end power supply, the positive terminal VO of the local-safety-end power supply is electrically connected with a resistor (R7), the other terminal of the resistor (R7) is electrically connected with a positive terminal of an on-off signal indicator lamp (D8), a negative terminal of the on-off signal indicator lamp (D8) is electrically connected with a negative terminal GO of the local-safety-end power supply, a 2 nd pin of a transformer (U1) is electrically connected with a negative terminal of the electrolytic capacitor (C1), the other terminal of the capacitor (C2), a positive terminal of a reference source (Q1) and a resistor (R6), a reference source (Q636) controls an extreme terminal of an electric resistor (R6), a positive, the negative end of a reference source (Q1) is electrically connected with the other end of a resistor (R5), the negative end of a diode (D3) and the source end of a field effect tube (Q2), the other end of a fuse (F1) is electrically connected with the negative end of a Zener diode (D4), the negative end of the Zener diode (D5), the negative end of the Zener diode (D6), a resistor (R1) and a resistor (R3), the other end of a resistor (R1) is electrically connected with the other end of a resistor (R3), a resistor (R2) and a resistor (R4), the other end of a resistor (R2) is electrically connected with the other end of the resistor (R4) and the 1 st pin of an output terminal (U2A), and the drain end of the field effect tube (Q2) is electrically connected with the positive end of the Zener diode (D4), the positive end of the Zener diode (D5), the positive end of the Zener diode (D6) and the 2 nd.
The communication equipment switching value output type explosion-proof safety barrier can limit the energy of switching value equipment, simultaneously carry out explosion-proof treatment, limit the energy on a data line when a switching value signal is transmitted to a dangerous site, ensure that the energy is not enough to ignite explosive mixtures, simultaneously electrically isolate the two equipment, and enhance the anti-interference performance and the safety of an industrial control network. For example, if the electromagnetic valve is electrically connected to a non-explosion natural gas on-off controller, reliable communication guarantee can be realized by adding the electromagnetic valve provided by the invention, switching value signals of the controller are transmitted to field equipment and simultaneously subjected to explosion-proof treatment, any switching value signal in the controller is transmitted to the field, the energy on a line is not enough to ignite explosive mixtures, and meanwhile, the two equipment are electrically isolated, so that the safety and the reliability of industrial control are enhanced.
The communication equipment switching value output type explosion-proof safety barrier receives a switching value signal from a safety area, isolates an explosion-proof treatment and transmits the signal to equipment in a dangerous area, and can control the output of an intrinsic safety end through a dry contact, an open-circuit signal of a collector or a logic level signal to drive the intrinsic safety end low-power equipment or other unit combination instruments in the dangerous area. Such as electromagnetic valve, audible and visual alarm, etc. The input, the output and the power supply are isolated from each other at three ends, so that the interference of an industrial complex environment can be resisted, the reliability and the safety are improved, the requirements of II C-level intrinsic safety and explosion prevention are met, the output stability is high, and the production operation safety in a flammable and explosive environment can be protected. The safety barrier and the dangerous area are separated, the energy on the transmission line is limited in a safe range, and the safety barrier is very convenient and practical.
The invention has good effect.

Claims (4)

1. An explosion-proof safety barrier for communication equipment switch output comprises an input end power management circuit, a transformer output rectifying and filtering circuit and an explosion-proof processing circuit at the intrinsic safety end, the input end power management circuit is characterized by comprising a pulse width modulation chip (U3), a transformer (U1), an input terminal (U2C) and an on-off signal indicator lamp (D8), wherein the input terminal (U2C) transmits signals to the pulse width modulation chip (U3), the pulse width modulation chip (U3) controls a primary coil of the transformer (U1), a feedback coil of the transformer (U1) feeds back signals to the pulse width modulation chip (U3), the voltage stabilizing function can be achieved, the transformer outputs a rectification filter circuit, signals are output to the rectification filter circuit through a secondary coil of the transformer (U1), and the signals are transmitted to an explosion-proof processing circuit at the local safety end after rectification and filtering and then are output through an output terminal (U2A). To the on-site hazardous area.
2. The switching value output type anti-explosion safety grid of communication equipment according to claim 1, wherein the 6 th pin of the input terminal (U2C) is electrically connected to the non-intrinsic safety end power supply cathode GND, the 5 th pin of the input terminal (U2C) is electrically connected to the capacitor (C5) and the fuse (F2), the other end of the capacitor (C5) is electrically connected to the non-intrinsic safety end power supply cathode GND, the other end of the fuse (F2) is electrically connected to the anode end of the diode (Q3), the cathode end of the diode (Q3) is electrically connected to the anode end of the electrolytic capacitor (C7), the resistor (R10), the collector of the triode (Q4), the resistor (R7) and the 12 th pin of the transformer (U1) and the non-intrinsic safety end power supply cathode VCC, the cathode end of the electrolytic capacitor (C7) is electrically connected to the non-intrinsic safety end power supply cathode GND, the other end of the resistor (R48) is electrically connected to the base of the triode (Q39 4) and the cathode end of the diode (D7), the, the triode (Q4) transmitter is electrically connected with the positive terminal of an electrolytic capacitor (C9) and the 7 th pin VCC of the pulse width modulation chip (U3), the negative terminal of a capacitor (C9) is electrically connected with the negative pole GND of a non-intrinsic safety end power supply, the other end of a resistor (R7) is electrically connected with a resistor (R9) and the 6 th pin UV of the pulse width modulation chip (U3), the other end of a resistor (R9) is electrically connected with a resistor (R13) and the 5 th pin OV of the pulse width modulation chip (U3), the other end of the resistor (R13) is electrically connected with the negative pole GND of the non-intrinsic safety end power supply, and the 8 th pin VD of the pulse width modulation chip (U3) is electrically connected with the.
3. The switching value output type explosion-proof safety barrier of communication equipment as claimed in claim 1, wherein the 4 th pin CMP of the pulse width modulation chip (U3) is electrically connected with the resistor (R12) and the capacitor (C6), the other end of the resistor (R12) is electrically connected with the capacitor (C8), the other end of the capacitor (C8) is electrically connected with the other end of the capacitor (C6), the resistor (R8), the resistor (R11) and the 3 rd pin FB of the pulse width modulation chip (U3), the 2 nd pin CT of the pulse width modulation chip (U3) is electrically connected with the capacitor (C4), the other end of the capacitor (C4) is electrically connected with the capacitor (C3), the 1 st pin GND of the pulse width modulation chip (U3) and the negative pole of the non-intrinsic-ampere-terminal power supply, the 10 th pin CT of the transformer (U1) is electrically connected with the negative pole of the non-GND-ampere-terminal, the 9 th pin of the transformer (U1) is electrically, the other end of the resistor (R11) is electrically connected with the negative pole GND of the non-intrinsic safety end power supply.
4. The switching value output type explosion-proof safety barrier of communication equipment as claimed in claim 1, wherein the 1 st pin of said transformer (U1) is electrically connected to the positive terminal of diode (D1), the negative terminal of diode (D1) is electrically connected to the positive terminal of electrolytic capacitor (C1), capacitor (C2), resistor (R5), fuse (F1) and positive terminal VO of intrinsically safe power supply, the positive terminal VO of intrinsically safe power supply is electrically connected to resistor (R7), the other terminal of resistor (R7) is electrically connected to the positive terminal of on-off signal indicator (D8), the negative terminal of on-off signal indicator (D8) is electrically connected to the negative terminal GO of intrinsically safe power supply, the 2 nd pin of transformer (U1) is electrically connected to the negative terminal of electrolytic capacitor (C1), the other terminal of capacitor (C2), the positive terminal of reference power supply (Q1) and resistor (R6), and reference power supply (Q1) controls the other terminal of resistor (R6) and the positive terminal of diode (D3), A grid end of a field effect transistor (Q2) and a cathode GO of a local safety end power supply, a cathode end of a reference source (Q1) is electrically connected with the other end of a resistor (R5), a cathode end of a diode (D3) and a source end of the field effect transistor (Q2), the other end of a fuse (F1) is electrically connected with a cathode end of a Zener diode (D4), a cathode end of a Zener diode (D5), a cathode end of the Zener diode (D6), a resistor (R1) and a resistor (R3), the other end of a resistor (R1) is electrically connected with the other end of the resistor (R3), a resistor (R2) and a resistor (R4), the other end of a resistor (R2) is electrically connected with the other end of the resistor (R4) and a 1 st pin of an output terminal (U2A), the drain end of the field effect transistor (Q2) is electrically connected with the positive end of the Zener diode (D4), the positive end of the Zener diode (D5), the positive end of the Zener diode (D6) and the No. 2 pin of the output terminal (U2A).
CN202010983950.6A 2020-09-09 2020-09-09 Communication equipment switching value output type explosion-proof safety barrier Pending CN112054497A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010983950.6A CN112054497A (en) 2020-09-09 2020-09-09 Communication equipment switching value output type explosion-proof safety barrier

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010983950.6A CN112054497A (en) 2020-09-09 2020-09-09 Communication equipment switching value output type explosion-proof safety barrier

Publications (1)

Publication Number Publication Date
CN112054497A true CN112054497A (en) 2020-12-08

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Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010983950.6A Pending CN112054497A (en) 2020-09-09 2020-09-09 Communication equipment switching value output type explosion-proof safety barrier

Country Status (1)

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CN (1) CN112054497A (en)

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