CN210626920U

CN210626920U - 16-channel isolation digital quantity transmission module based on RS-485 communication

Info

Publication number: CN210626920U
Application number: CN201921497574.9U
Authority: CN
Inventors: 蔡崇开
Original assignee: Quanzhou Guanhangda Electronic Technology Co ltd
Current assignee: Quanzhou Guanhangda Electronic Technology Co ltd
Priority date: 2019-09-10
Filing date: 2019-09-10
Publication date: 2020-05-26
Anticipated expiration: 2029-09-10

Abstract

The utility model discloses a 16 passageway keeps apart digital quantity transport module based on RS-485 communication, including digital quantity input circuit, digital quantity output circuit, first photoelectric isolator, second photoelectric isolator, microcontroller, electrical isolator, RS-485 transceiver and power supply circuit, digital quantity input circuit's output is connected with microcontroller through first photoelectric isolator, digital quantity output circuit's input passes through the second photoelectric isolator and is connected with microcontroller, the module is provided with 16 ways digital quantity passageways, every digital quantity passageway all configures alone into digital quantity input channel or digital quantity output channel, RS-485 transceiver passes through electrical isolator and is connected with microcontroller, power supply circuit provides stable operating voltage for the module. The utility model discloses conveniently gather switchgear such as various digital quantity signals and control relay of industrial field, output data has the safety protection function, has avoided the influence of industrial field signal to communication interface.

Description

16-channel isolation digital quantity transmission module based on RS-485 communication

Technical Field

The utility model belongs to the technical field of the data acquisition module, concretely relates to 16 passageway isolation digital quantity transport module based on RS-485 communication.

Background

In an industrial control process, it is often necessary to collect a digital input signal on site and control an actuator or a switching device on site by analyzing and outputting the digital quantity. For this reason, it is necessary to design a 16-channel isolation digital quantity transmission module based on RS-485 communication.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a 16 passageway isolation digital quantity transport module based on RS-485 communication.

In order to achieve the above purpose, the utility model adopts the following technical scheme: a16-channel isolation digital quantity transmission module based on RS-485 communication comprises a digital quantity input circuit, a digital quantity output circuit, a first photoelectric isolator, a second photoelectric isolator, a microcontroller, an electrical isolator, an RS-485 transceiver and a power supply circuit, wherein the output end of the digital quantity input circuit is connected with the microcontroller through the first photoelectric isolator, the input end of the digital quantity output circuit is connected with the microcontroller through the second photoelectric isolator, the module is provided with 16 digital quantity channels, each digital quantity channel is independently configured to be a digital quantity input channel or a digital quantity output channel, the RS-485 transceiver is connected with the microcontroller through the electrical isolator, and the power supply circuit provides stable working voltage for the module.

Preferably, the microcontroller further comprises a watchdog circuit, and the watchdog circuit is connected with the microcontroller.

Preferably, the microcontroller further comprises an EEPROM memory, and the EEPROM memory is connected with the microcontroller.

Preferably, the input type of the digital input channel is a switch contact signal or a level signal, and the output type of the digital output channel is a collector open-drain output.

Preferably, the power supply device further comprises a power supply indicator light and a working state indicator light, wherein the power supply indicator light is connected with the power supply circuit, and the working state indicator light is respectively connected with the power supply circuit and the microcontroller.

Preferably, the power supply circuit comprises a main power supply circuit, a secondary voltage stabilizing circuit and an isolation power supply circuit, wherein an output end of the main power supply circuit is respectively connected with an input end of the secondary voltage stabilizing circuit and an input end of the isolation power supply circuit, one output end of the isolation power supply circuit is connected to the digital quantity input circuit, the other output end of the isolation power supply circuit is connected to the digital quantity output circuit, and an output end of the secondary voltage stabilizing circuit is connected to the digital quantity output circuit, the microcontroller and the RS-485 transceiver.

Preferably, the microcontroller employs a 32-bit RISC CPU ARM chip.

The utility model discloses following beneficial effect has: the module is provided with 16 paths of digital quantity isolation channels which can be configured as input or output channels, so that various digital quantity signals of an industrial field can be conveniently acquired, switching equipment such as a relay can be controlled, and the module can be widely applied to various industrial fields; the RS-485 communication interface with isolation is adopted, so that the influence of industrial field signals on the communication interface of the microcontroller is avoided, and the microcontroller has ESD (Electro-Static Discharge), overvoltage and overcurrent protection functions; the module output data has a safety protection function, and a user can set a group of output states when the module and the host computer lose communication, so that the safety of the controlled equipment is not influenced.

Drawings

Fig. 1 is a schematic block diagram of an embodiment of the present invention.

Fig. 2 is a circuit diagram of a microcontroller according to an embodiment of the present invention.

Fig. 3 is a circuit diagram of a compatible connection between a 1-way digital quantity input circuit and a 1-way digital quantity output circuit according to an embodiment of the present invention.

Fig. 4 is a circuit diagram of an isolated RS-485 transceiver according to an embodiment of the present invention.

Fig. 5 is an integrated circuit diagram of the watchdog circuit and the EEPROM memory according to the embodiment of the present invention.

Fig. 6 is a circuit diagram of a power indicator according to an embodiment of the present invention.

Fig. 7 is a circuit diagram of an operating status indicator light according to an embodiment of the present invention.

Fig. 8 is a circuit diagram of a main power circuit according to an embodiment of the present invention.

Fig. 9 is a circuit diagram of a two-stage voltage regulator circuit according to an embodiment of the present invention.

Fig. 10 is a circuit diagram of an isolated power circuit according to an embodiment of the present invention.

The labels in the figure are: 1. a digital quantity input circuit; 2. a digital quantity output circuit; 3. a first opto-isolator; 4. a second opto-isolator; 5. a microcontroller; 6. an electrical isolator; 7. an RS-485 transceiver; 8. a power supply circuit; 9. a watchdog circuit; 10. an EEPROM memory.

Detailed Description

In order to make the aforementioned and other features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

As shown in fig. 1, the present embodiment provides a 16-channel isolated digital quantity transmission module based on RS-485 communication, including a digital quantity input circuit 1, a digital quantity output circuit 2, a first optoelectronic isolator 3, a second optoelectronic isolator 4, a microcontroller 5, an electrical isolator 6, an RS-485 transceiver 7, and a power supply circuit 8, where an output end of the digital quantity input circuit 1 is connected to the microcontroller 5 through the first optoelectronic isolator 3, an input end of the digital quantity output circuit 2 is connected to the microcontroller 5 through the second optoelectronic isolator 4, the module is provided with 16 digital quantity channels, each digital quantity channel is independently configured as a digital quantity input channel or a digital quantity output channel, the RS-485 transceiver 7 is connected to the microcontroller 5 through the electrical isolator 6, and the power supply circuit 8 provides a stable operating voltage for the entire module.

In this embodiment, the microcontroller 5 adopts a 32-bit RISC CPU ARM chip, specifically adopts an LPC2131 single chip microcomputer as shown in fig. 2, has a very fast data processing capability, and can be applied in a high-performance and high-speed application environment; operating the system: a real-time operating system; supply voltage: +10 to +30V_DCThe power source is reversely connected for protection; working temperature range: -20 ℃ to +85 ℃; an industrial grade plastic housing, mounted with standard DIN rails; communication interface: isolation 2500V_DCESD, overvoltage, overcurrent protection.

In the present embodiment, the 16 digital quantity channels are public connection terminals, and the connections of the digital quantity input channel and the digital quantity output channel on the terminals are as shown in fig. 3, wherein the first optoelectronic isolator 3 is preferably but not limited to a PC354NT optical coupler, and the second optoelectronic isolator 4 is preferably but not limited to a TLP281 optical coupler. The working mode of the current channel needs to be configured before use, and the current channel can be configured as input or output through software. When the DI input is selected, the module outputs internal DO as high level by default, namely, the triode is cut off, and the state of the channel is ensured to be consistent with the external signal. When the channel is selected as the DO output, the user can control the output value of the channel, and can read the output value of the current port through the DI channel. At this time, the user cannot externally input signals on the channel, otherwise, the module or the external equipment can be damaged. The factory default configuration channel is the DI input mode.

In the embodiment, the input type of the digital input channel is a switch contact signal or a level signal; input range: high level (digital 1): + 3.5V to +50V, low level (digital 0): less than or equal to + 1V; switch contact effective input impedance: less than or equal to 1k omega; DI count signal: frequency of<2kHz, high level hold time>200 us; isolation and pressure resistance: 2500 VDC. The output type of the digital output channel is collector open-drain output, and the maximum load voltage is as follows: 50V, maximum load current: 50mA, isolation withstand voltage: 2500V_DC。

In this embodiment, the electrical isolator 6 and the RS-485 transceiver 7 are preferably, but not limited to, an RSM3485C isolation transceiver module as shown in fig. 4, and the RSM3485C isolation transceiver module integrates power isolation, electrical isolation, an RS-485 interface chip and a bus protection device, so as to be conveniently embedded in a user equipment, so that the product has a function of connecting to an RS-485 network.

In the present embodiment, the 16-channel isolated digital quantity transmission module based on RS-485 communication further comprises a watchdog circuit 9 and an EEPROM memory 10, the watchdog circuit 9 and the EEPROM memory 10 are respectively connected with the microcontroller 5, the watchdog circuit 9 and the EEPROM memory 10 are preferably, but not limited to, a CAT1023 monitoring circuit as shown in fig. 5, and the CAT1023 monitoring circuit is a complete solution for memory and power supply monitoring based on a microcontroller system. The watchdog circuit 9 is adopted, so that the system of the module can be restarted when an accident occurs, and the system is more stable and reliable.

In this embodiment, the 16-channel isolated digital quantity transmission module based on RS-485 communication further includes a power indicator shown in fig. 6 and a working status indicator shown in fig. 7, the power indicator is connected to the power circuit 8, and the working status indicator is connected to the power circuit 8 and the microcontroller 5, respectively. The power supply indicator lamp is a red indicator lamp, and when the lamp is on, the power supply of the module is normal; the working state indicator light is a red-green double-color indicator light, the fact that the module is not electrified or does not operate is indicated when the light is not on, the fact that the module is initialized to make mistakes is indicated when the red light is on, the fact that the module normally operates but does not communicate with the host machine is indicated when the green light is normally on, and the fact that the module is connected with the host machine and normally communicates is indicated when the green light flickers.

In this embodiment, the power supply circuit 8 includes a main power supply circuit, a secondary voltage stabilizing circuit and an isolation power supply circuit, an output end of the main power supply circuit is respectively connected to an input end of the secondary voltage stabilizing circuit and an input end of the isolation power supply circuit, an output end of the isolation power supply circuit is connected to the digital input circuit 1, another output end of the isolation power supply circuit is connected to the digital output circuit 2, an output end of the secondary voltage stabilizing circuit is connected to the digital output circuit 2, the microcontroller 5, the RS-485 transceiver 7, the power indicator lamp, the working state indicator lamp and the like, and the voltage is more stable and reliable. The main power supply circuit is preferably but not limited to a TPS5430 power supply module shown in FIG. 8, the secondary voltage stabilizing circuit is preferably but not limited to an SP6201EM5-L-3.3 power supply module shown in FIG. 9, and the isolated power supply circuit is preferably but not limited to a ZY0505FKS-1W power supply module shown in FIG. 10.

The working principle of the embodiment is as follows: the module integrates functions of digital quantity input and output, data processing, RS-485 communication and the like, supports 16 paths of digital quantity isolation channels, and each channel can be independently configured to be input or output; the digital input supports switch contact signals and level signals, so that various digital signals of an industrial field and switch equipment such as a control relay can be conveniently acquired, and the digital input can be widely applied to various industrial fields; when the module and the host computer are not successfully communicated after exceeding the set safe time, the module outputs the set safe output value to protect the safety of the control equipment and restores the state of the module to be the unconnected state; the RS-485 communication interface with isolation is adopted, so that the influence of industrial field signals on the communication interface of the microcontroller is avoided, and the device has ESD, overvoltage and overcurrent protection functions.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and any person skilled in the art should not depart from the technical solution of the present invention, and any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the scope of the present invention.

Claims

1. A16-channel isolation digital quantity transmission module based on RS-485 communication is characterized in that: the digital quantity monitoring module comprises a digital quantity input circuit, a digital quantity output circuit, a first photoelectric isolator, a second photoelectric isolator, a microcontroller, an electrical isolator, an RS-485 transceiver and a power supply circuit, wherein the output end of the digital quantity input circuit is connected with the microcontroller through the first photoelectric isolator, the input end of the digital quantity output circuit is connected with the microcontroller through the second photoelectric isolator, the module is provided with 16 digital quantity channels, each digital quantity channel is independently configured into a digital quantity input channel or a digital quantity output channel, the RS-485 transceiver is connected with the microcontroller through the electrical isolator, and the power supply circuit provides stable working voltage for the module; the power supply circuit comprises a main power supply circuit, a secondary voltage stabilizing circuit and an isolation power supply circuit, wherein the output end of the main power supply circuit is respectively connected with the input end of the secondary voltage stabilizing circuit and the input end of the isolation power supply circuit, one output end of the isolation power supply circuit is connected to the digital quantity input circuit, the other output end of the isolation power supply circuit is connected to the digital quantity output circuit, and the output end of the secondary voltage stabilizing circuit is connected to the digital quantity output circuit, the microcontroller and the RS-485 transceiver.

2. The RS-485 communication based 16-channel isolated digital quantity transport module according to claim 1, wherein: the watch dog circuit is connected with the microcontroller.

3. The RS-485 communication based 16-channel isolated digital quantity transport module according to claim 1 or 2, wherein: the microcontroller is connected with the power supply, and the power supply is connected with the microcontroller.

4. The RS-485 communication based 16-channel isolated digital quantity transport module according to claim 1, wherein: the input type of the digital quantity input channel is a switch contact signal or a level signal, and the output type of the digital quantity output channel is collector open-drain output.

5. The RS-485 communication based 16-channel isolated digital quantity transport module according to claim 1, wherein: the power supply circuit is characterized by further comprising a power supply indicating lamp and a working state indicating lamp, wherein the power supply indicating lamp is connected with the power supply circuit, and the working state indicating lamp is connected with the power supply circuit and the microcontroller respectively.

6. The RS-485 communication based 16-channel isolated digital quantity transport module according to claim 1, wherein: the microcontroller adopts a 32-bit RISC CPU ARM chip.