CN202486563U - PLC digital value input interface circuit - Google Patents
PLC digital value input interface circuit Download PDFInfo
- Publication number
- CN202486563U CN202486563U CN2011204901085U CN201120490108U CN202486563U CN 202486563 U CN202486563 U CN 202486563U CN 2011204901085 U CN2011204901085 U CN 2011204901085U CN 201120490108 U CN201120490108 U CN 201120490108U CN 202486563 U CN202486563 U CN 202486563U
- Authority
- CN
- China
- Prior art keywords
- circuit
- resistance
- plc
- light emitting
- emitting diode
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Electronic Switches (AREA)
Abstract
The utility model discloses a PLC digital value input interface circuit, and relates to the PLC technology field. The PLC digital value input interface circuit includes an external contact circuit (1), a signal input circuit (2), and a PLC internal processing circuit (3). The external contact circuit (1) is connected with the signal input circuit (2). The signal input circuit (2) is connected with the PLC internal processing circuit (3). The PLC digital value input interface circuit can detect whether or not a switching value input line of a passive contact or a sensor breaks, thus improving the authenticity of a detection signal and the reliability of a control system. Besides, the PLC digital value input interface circuit has the characteristics of simple structure, reliable detection, and strong practicality.
Description
Technical field:
The utility model relates to the PLC technical field, is specifically related to a kind of PLC digital-quantity input interface circuit.
Background technology:
In the industrial control system, PLC is very general to the switching value signals collecting such as sensor of the passive contact or the NPN type open collector way of output.If the signal input line route in machinery pull, broken string appears in reasons such as circuit self is aging, the plague of rats; On-site signal can't send PLC to; Then can not collect on-site signal correctly, in time; And fault is not easy to discover, and can reduce the authenticity of detection signal and the reliability of control system.
The utility model content:
Whether the purpose of the utility model provides a kind of PLC digital-quantity input interface circuit, and it not only can gather contact information, and have and exist broken string to carry out measuring ability to the signal input line road.
In order to solve the existing problem of background technology; The utility model is to adopt following technical scheme: it comprises external contact circuit 1, signal input circuit 2 and PLC inter-process circuit 3; External contact circuit 1 is connected with signal input circuit 2, and signal input circuit 2 is connected with PLC inter-process circuit 3.
Described external contact circuit 1 comprises switch S 1 and resistance R 1, and switch S 1 is connected in parallel with resistance R 1.
Described signal input circuit 2 is made up of direct-flow input circuit 4 and ac input circuit 5.
Described direct-flow input circuit 4 comprises resistance R 2-R4, light emitting diode VD1-VD2 and photoelectrical coupler U1; Input terminal A1 is connected with an end of resistance R 2; The other end of resistance R 2 is connected with an end of resistance R 3 and 1 end of photoelectrical coupler U1 respectively; The other end of resistance R 3 is connected with input terminal B1, and 2 ends of photoelectrical coupler U1 are connected with the positive pole of light emitting diode VD1, and the negative pole of light emitting diode VD1 is connected with input terminal B1; 3 ends of photoelectrical coupler U1 are connected with the negative pole of light emitting diode VD2 and an end of PLC inter-process circuit 3 respectively; The positive pole of light emitting diode VD2 is connected with an end of resistance R 4, and the other end of resistance R 4 is connected with working power VDD, and 4 ends of photoelectrical coupler U1 are connected with the other end of PLC inter-process circuit 3.
Described ac input circuit 5 comprises resistance R 6-R8; Capacitor C 1, bridge rectifier D 1, light emitting diode VD3-VD4 and photoelectrical coupler U2; Input terminal A2 is connected with an end of resistance R 6, and the other end of resistance R 6 is connected with the positive pole of capacitor C 1, and the negative pole of capacitor C 1 is connected with 5 ends of bridge rectifier D 1; 7 ends of bridge rectifier D 1 are connected with input terminal B2; 8 ends of bridge rectifier D 1 are connected with 9 ends of an end of resistance R 7 and photoelectrical coupler U2, and 10 ends of photoelectrical coupler U2 are connected with the positive pole of light emitting diode VD3, and the other end of the negative pole of light emitting diode VD3 and resistance R 7 all is connected with 6 ends of bridge rectifier D 1; 11 ends of photoelectrical coupler U2 are connected with the negative pole of light emitting diode VD4 and an end of PLC inter-process circuit 3 respectively; The positive pole of light emitting diode VD4 is connected with an end of resistance R 8, and the other end of resistance R 8 is connected with working power VDD, and 12 ends of photoelectrical coupler U2 are connected with the other end of PLC inter-process circuit 3.
Whether described signal input circuit 2 is used to detect on-the-spot contact switch closed.When the switch of external contact circuit 1 did not have closure, the not conducting of photoelectrical coupler of signal input circuit 2 sent 3 one noble potentials of PLC inter-process circuit to, and the expression signal input port does not have the signal input; When the switch closure of external contact circuit 1, signal input circuit 2 photoelectrical coupler conductings send 3 one electronegative potentials of PLC inter-process circuit to, and the expression signal input port has the signal input.
Described resistance R 4 is formed the burn out detection indicating circuit with resistance R 8, light emitting diode VD2 and light emitting diode VD4, and when circuit did not break, light emitting diode VD2 and light emitting diode VD4 were bright; When broken string took place, light emitting diode VD2 and light emitting diode VD4 went out.
Whether the utility model can exist broken string to detect the incoming line of switching values such as passive contact or sensor, has increased the authenticity of detection signal and the reliability of control system, have simple in structure, detect reliably.Characteristics such as practical.
Description of drawings:
Fig. 1 is the structural representation of the utility model.
Fig. 2 is the structural representation of direct-flow input circuit in the utility model.
Fig. 3 is the structural representation of ac input circuit in the utility model.
Embodiment:
With reference to Fig. 1-Fig. 3; This embodiment adopts following technical scheme: it comprises external contact circuit 1, signal input circuit 2 and PLC inter-process circuit 3; External contact circuit 1 is connected with signal input circuit 2, and signal input circuit 2 is connected with PLC inter-process circuit 3.
Described external contact circuit 1 comprises switch S 1 and resistance R 1, and switch S 1 is connected in parallel with resistance R 1.
Described signal input circuit 2 is made up of direct-flow input circuit 4 and ac input circuit 5.
Described direct-flow input circuit 4 comprises resistance R 2-R4, light emitting diode VD1-VD2 and photoelectrical coupler U1; Input terminal A1 is connected with an end of resistance R 2; The other end of resistance R 2 is connected with an end of resistance R 3 and 1 end of photoelectrical coupler U1 respectively; The other end of resistance R 3 is connected with input terminal B1, and 2 ends of photoelectrical coupler U1 are connected with the positive pole of light emitting diode VD1, and the negative pole of light emitting diode VD1 is connected with input terminal B1; 3 ends of photoelectrical coupler U1 are connected with the negative pole of light emitting diode VD2 and an end of PLC inter-process circuit 3 respectively; The positive pole of light emitting diode VD2 is connected with an end of resistance R 4, and the other end of resistance R 4 is connected with working power VDD, and 4 ends of photoelectrical coupler U1 are connected with the other end of PLC inter-process circuit 3.
Described ac input circuit 5 comprises resistance R 6-R8; Capacitor C 1, bridge rectifier D 1, light emitting diode VD3-VD4 and photoelectrical coupler U2; Input terminal A2 is connected with an end of resistance R 6, and the other end of resistance R 6 is connected with the positive pole of capacitor C 1, and the negative pole of capacitor C 1 is connected with 5 ends of bridge rectifier D 1; 7 ends of bridge rectifier D 1 are connected with input terminal B2; 8 ends of bridge rectifier D 1 are connected with 9 ends of an end of resistance R 7 and photoelectrical coupler U2, and 10 ends of photoelectrical coupler U2 are connected with the positive pole of light emitting diode VD3, and the other end of the negative pole of light emitting diode VD3 and resistance R 7 all is connected with 6 ends of bridge rectifier D 1; 11 ends of photoelectrical coupler U2 are connected with the negative pole of light emitting diode VD4 and an end of PLC inter-process circuit 3 respectively; The positive pole of light emitting diode VD4 is connected with an end of resistance R 8, and the other end of resistance R 8 is connected with working power VDD, and 12 ends of photoelectrical coupler U2 are connected with the other end of PLC inter-process circuit 3.
Whether described signal input circuit 2 is used to detect on-the-spot contact switch closed.When the switch of external contact circuit 1 did not have closure, the not conducting of photoelectrical coupler of signal input circuit 2 sent 3 one noble potentials of PLC inter-process circuit to, and the expression signal input port does not have the signal input; When the switch closure of external contact circuit 1, signal input circuit 2 photoelectrical coupler conductings send 3 one electronegative potentials of PLC inter-process circuit to, and the expression signal input port has the signal input.
Described resistance R 4 is formed the burn out detection indicating circuit with resistance R 8, light emitting diode VD2 and light emitting diode VD4, and when circuit did not break, light emitting diode VD2 and light emitting diode VD4 were bright; When broken string took place, light emitting diode VD2 and light emitting diode VD4 went out.
Whether this embodiment can exist broken string to detect the incoming line of switching values such as passive contact or sensor, has increased the authenticity of detection signal and the reliability of control system, have simple in structure, detect reliably.Characteristics such as practical.
Claims (5)
1. PLC digital-quantity input interface circuit; It is characterized in that it comprises external contact circuit (1), signal input circuit (2) and PLC inter-process circuit (3); External contact circuit (1) is connected with signal input circuit (2), and signal input circuit (2) is connected with PLC inter-process circuit (3).
2. a kind of PLC digital-quantity input interface circuit according to claim 1 is characterized in that described external contact circuit (1) comprises switch S 1 and resistance R 1, and switch S 1 is connected in parallel with resistance R 1.
3. a kind of PLC digital-quantity input interface circuit according to claim 1 is characterized in that described signal input circuit (2) is made up of direct-flow input circuit (4) and ac input circuit (5).
4. a kind of PLC digital-quantity input interface circuit according to claim 3; It is characterized in that described direct-flow input circuit (4) comprises resistance R 2, R3, R4, light emitting diode VD1, VD2 and photoelectrical coupler U1; Input terminal A1 is connected with an end of resistance R 2; The other end of resistance R 2 is connected with an end of resistance R 3 and 1 end of photoelectrical coupler U1 respectively; The other end of resistance R 3 is connected with input terminal B1, and 2 ends of photoelectrical coupler U1 are connected with the positive pole of light emitting diode VD1, and the negative pole of light emitting diode VD1 is connected with input terminal B1; 3 ends of photoelectrical coupler U1 are connected with the negative pole of light emitting diode VD2 and an end of PLC inter-process circuit (3) respectively; The positive pole of light emitting diode VD2 is connected with an end of resistance R 4, and the other end of resistance R 4 is connected with working power VDD, and 4 ends of photoelectrical coupler U1 are connected with the other end of PLC inter-process circuit (3).
5. a kind of PLC digital-quantity input interface circuit according to claim 3; It is characterized in that described ac input circuit (5) comprises resistance R 6, R7, R8; Capacitor C 1, bridge rectifier D 1, light emitting diode VD3, VD4 and photoelectrical coupler U2; Input terminal A2 is connected with an end of resistance R 6, and the other end of resistance R 6 is connected with the positive pole of capacitor C 1, and the negative pole of capacitor C 1 is connected with 5 ends of bridge rectifier D 1; 7 ends of bridge rectifier D 1 are connected with input terminal B2; 8 ends of bridge rectifier D 1 are connected with 9 ends of an end of resistance R 7 and photoelectrical coupler U2, and 10 ends of photoelectrical coupler U2 are connected with the positive pole of light emitting diode VD3, and the other end of the negative pole of light emitting diode VD3 and resistance R 7 all is connected with 6 ends of bridge rectifier D 1; 11 ends of photoelectrical coupler U2 are connected with the negative pole of light emitting diode VD4 and an end of PLC inter-process circuit (3) respectively; The positive pole of light emitting diode VD4 is connected with an end of resistance R 8, and the other end of resistance R 8 is connected with working power VDD, and 12 ends of photoelectrical coupler U2 are connected with the other end of PLC inter-process circuit (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011204901085U CN202486563U (en) | 2011-11-30 | 2011-11-30 | PLC digital value input interface circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011204901085U CN202486563U (en) | 2011-11-30 | 2011-11-30 | PLC digital value input interface circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202486563U true CN202486563U (en) | 2012-10-10 |
Family
ID=46960972
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011204901085U Expired - Fee Related CN202486563U (en) | 2011-11-30 | 2011-11-30 | PLC digital value input interface circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202486563U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104597822A (en) * | 2013-10-31 | 2015-05-06 | 施耐德电器工业公司 | Digital input line break detection method and circuit |
| CN105301484A (en) * | 2014-05-30 | 2016-02-03 | 国网山西省电力公司电力科学研究院 | Passive contact testing device |
| CN108958141A (en) * | 2018-05-02 | 2018-12-07 | 李献云 | Digital input circuit broken string real-time detection method and circuit |
-
2011
- 2011-11-30 CN CN2011204901085U patent/CN202486563U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104597822A (en) * | 2013-10-31 | 2015-05-06 | 施耐德电器工业公司 | Digital input line break detection method and circuit |
| CN105301484A (en) * | 2014-05-30 | 2016-02-03 | 国网山西省电力公司电力科学研究院 | Passive contact testing device |
| CN108958141A (en) * | 2018-05-02 | 2018-12-07 | 李献云 | Digital input circuit broken string real-time detection method and circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201084002Y (en) | PLC digital quantity input interface circuit | |
| CN103063979B (en) | Load open-circuit detection circuit | |
| CN204065213U (en) | Zero sequence current mutual inductor break detection circuit and residual current detection circuit | |
| CN202486563U (en) | PLC digital value input interface circuit | |
| CN104198794A (en) | Zero sequence current transformer wire-break detection and residual current detection circuit | |
| CN103499748A (en) | Online monitoring system of supercapacitor bank | |
| CN103454581A (en) | Contactor performance testing equipment | |
| CN201335880Y (en) | Shaft current detection device for generator | |
| CN203941243U (en) | A kind of three-phase electric power open phase testing circuit | |
| CN203688642U (en) | Power failure detection circuit | |
| CN103728488A (en) | Wind driven generator over-temperature detecting method and system | |
| CN203616424U (en) | A novel battery reversal connection detection circuit | |
| CN203118869U (en) | Relay control circuit | |
| CN203572900U (en) | Broken line detection circuit for state grid special transformer collection terminal control circuit | |
| CN202976407U (en) | Earthquake alarm | |
| CN202383233U (en) | Diagnosis circuit for low-voltage differential signal cable of automobile | |
| CN202435029U (en) | Battery reverse connection prevention circuit | |
| CN204615365U (en) | A kind of permagnetic synchronous motor back electromotive force protective device | |
| CN209446725U (en) | The insulating gate type field effect tube detection circuit of open loop push-pull converter | |
| CN203761361U (en) | Level shift circuit | |
| CN204347175U (en) | A kind of lightning current HF reject device with monitoring function | |
| CN208707308U (en) | A kind of power supply reverse connection protection device | |
| CN205355780U (en) | PFC current foldback circuit | |
| CN201434671Y (en) | Ice covering thickness testing device for high-voltage transmission line | |
| CN204480446U (en) | Coal gas explosion alarm and power circuit thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20121010 Termination date: 20131130 |