CN216871047U

CN216871047U - 485 communication module

Info

Publication number: CN216871047U
Application number: CN202123435872.5U
Authority: CN
Inventors: 张腾飞; 毛犇; 赖济民; 毛生辉; 胡钱波; 金海波; 余挺; 王圆; 高鹏强; 周冉冉; 郭志豪
Original assignee: Ningbo Sanxing Smart Electric Co Ltd
Current assignee: Ningbo Sanxing Smart Electric Co Ltd
Priority date: 2021-12-29
Filing date: 2021-12-29
Publication date: 2022-07-01
Anticipated expiration: 2031-12-29

Abstract

The utility model relates to a 485 communication module, which comprises a 485 module (2) in communication connection with an upper computer (1), an MCU (micro control unit) module (4) in communication connection with the 485 module (2) and an ammeter (3) respectively, and a power isolation module (5) arranged between the 485 module (2) and the ammeter (3) for isolating power supply voltage. The communication module improves the safety of the ammeter, and the application range of the ammeter is greatly improved.

Description

485 communication module

Technical Field

The utility model relates to the technical field of electric meters, in particular to a 485 communication module.

Background

Along with smart electric meter's popularization and industry divide the labour to refine more and more, the ammeter modularization becomes the tendency, and the designer carries out the modularized design with the ammeter structure according to the function, then assembles a plurality of modules and forms required ammeter, and the 485 communication module is born under this situation promptly.

The designer pegs graft the 485 communication module on the table, and the ammeter communicates with the host computer through the 485 communication module. But current 485 communication module designs still have some problems, for example current 485 communication module can't realize the power isolation, can't avoid human contact jaw and forceful electric power end to keep apart, has the potential safety hazard.

Simultaneously, current 485 communication module power is got from the ammeter, and the circuit design relation between this module and the ammeter can't effectively prevent the electric current refluence of ammeter to 485 communication module in, also has certain safety problem.

SUMMERY OF THE UTILITY MODEL

In view of the above problems, an object of the present invention is to provide a 485 communication module having a simple structure and high safety.

In order to achieve the purpose, the technical scheme of the utility model is as follows: the utility model provides a 485 communication module, 485 communication module includes the 485 module that links to each other with host computer communication, and the MCU module of being connected with 485 module and ammeter difference communication, its characterized in that:

the 485 communication module further comprises a power isolation module arranged between the 485 module and the ammeter and used for isolating power supply voltage.

Further, the power isolation module comprises an isolation transformer electrically connected between the ammeter and the 485 module.

Furthermore, the power isolation module further comprises a voltage stabilizing module arranged between the isolation transformer and the 485 module.

Further, the voltage stabilizing module comprises an AZ431 voltage stabilizing tube which is electrically connected with the isolation transformer and the 485 module.

Further, the 485 module comprises an NSi83085 type isolation chip with a capacitance-coupling isolation function, and a power supply end of the isolation chip is connected with an output end of the voltage stabilizing module.

Further, the MCU module adopts an FM3313 chip which can automatically identify and convert 485 communication baud rate.

Furthermore, an open-drain output module with a backflow prevention function is arranged between the signal output pin of the MCU module and the ammeter.

Furthermore, the open-drain output module comprises an NPN type triode, wherein the base electrode of the NPN type triode is connected with the signal output pin of the MCU module, the collector electrode of the NPN type triode is electrically connected with the ammeter, and the emitter of the NPN type triode is grounded.

Further, the 485 communication module also comprises a module indicator light for indicating the communication state of the 485 communication module.

Further, the module pilot lamp is including the red pilot lamp that is used for marking communication status between module and the ammeter and the green pilot lamp that is used for marking communication status between module and the host computer.

Compared with the prior art, the utility model has the advantages that:

by arranging the isolation transformer between the ammeter and the 485 module and adopting the 485 chip with the capacitance-coupling isolation function, the signal isolation and the communication port isolation between the 485 communication module and the power end of the ammeter can be effectively realized, the contact between a human body contact end and a strong electric end is avoided, and the safety of the ammeter is improved; the arrangement of the open-drain output module can effectively prevent the current of the electric meter from flowing backwards, and the overall stability of the electric meter is improved; the MCU module adopts a chip with the functions of automatically identifying and converting the communication baud rate, so that the baud rate self-adaption of the electric meter can be realized, and the application range of the electric meter is improved; the design of module pilot lamp, the communication state between 485 communication module of being convenient for operating personnel directly perceivedly looking over, ammeter and the host computer has improved convenient operation nature.

Drawings

Fig. 1 is a block diagram of a 485 communication module according to the present application.

Fig. 2 is a schematic circuit diagram of a 485 module in the 485 communication module of the present application.

Fig. 3 is a schematic diagram of a power isolation module circuit in the 485 communication module of the present application.

Fig. 4 is a schematic circuit diagram of the MCU module, the open-drain output module, and the module indicator lamp in the 485 communication module of the present application.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

As shown in fig. 1-4, in the preferred embodiment of the 485 communication module, the 485 communication module includes a 485 module 2 communicatively connected to an upper computer 1, and an MCU module 4 communicatively connected to the 485 module 2 and an electric meter 3, respectively, in order to solve the problem of power isolation, effectively avoid the contact of the human body contact end with the strong electric power end, and improve the safety, the 485 communication module further includes a power isolation module 5 disposed between the 485 module 2 and the electric meter 3 to isolate the power voltage.

In the present embodiment, as shown in fig. 3, the power isolation module 5 includes an isolation transformer T1 electrically connected between the electricity meter 3 and the 485 module 2. The isolation transformer T1 can convert the 5V voltage from the electricity meter into 5V voltage for the 485 module 2, but in order to ensure the power supply stability, the circuit further includes a voltage stabilizing module 6 disposed between the isolation transformer T1 and the 485 module 2, and in particular, in this embodiment, the voltage stabilizing module 6 includes an AZ431 zener N4 electrically connected to the isolation transformer T1 and the 485 module 2.

In order to further ensure the isolation of the communication port, the 485 module 2 includes an isolation 485 chip N2, and specifically, in this application, the isolation chip N2 is a NSi83085 type isolation chip having a capacitive isolation function, and a power supply terminal of the isolation chip is connected to an output terminal of the voltage regulator module 6, as shown in fig. 2. Meanwhile, the communication rate of the chip reaches 115200bps, and the chip can bear 5kV alternating-current voltage and is safe and reliable.

When the ammeter is in intercommunication with the host computer, according to current design, both sides must pass through once matching collision, just can find the baud rate that is fit for each other and will communicate, and this has seriously influenced communication efficiency, and in order to solve this problem, MCU module 4 in this application adopts FM3313 chip N1 that has automatic identification and conversion 485 communication baud rate.

The chip of the type has wide communication baud rate and can realize self-adaptation, so that when an upper computer communicates at any baud rate of 1200-year 115200bps, a 485 communication module can identify, the communication efficiency of the electric meter is greatly improved, obviously, under the condition, the baud rate of the electric energy meter can be set, the setting range of the baud rate is between 1200-year 115200bps, and in the actual application process, the default baud rate of the electric meter is 9600 bps.

In order to further improve the safety and stability of the circuit, an open-drain output module 7 with a backflow prevention function is arranged between the signal output pin 12 of the MCU module 4 and the electric meter 3. As shown in fig. 4, the open-drain output module 7 includes an NPN transistor V1 having a base connected to the signal output pin 12 of the MCU module 4, a collector electrically connected to the electric meter 3, and a transmitter grounded.

For the clear operational aspect that shows 485 communication module, this 485 communication module still includes the module pilot lamp 8 that is used for marking 485 communication module running state.

As shown in fig. 4, the module indicating lamp 8 includes a red indicating lamp HL1 for indicating an operation state between the module and the electricity meter 3 and a green indicating lamp HL2 for indicating an operation state between the module and the upper computer 1.

Specifically, when the red indicator lamp HL1 is turned off, it indicates that the module is in normal communication with the electric meter 3, when the module is normally on, it indicates that the module is in abnormal communication with the electric meter, and when the module is in flashing, for example, the module is turned on for 1s and then turned off for 1s, it indicates that data exchange is in progress between the module and the electric meter; the green indicator lamp HL2 indicates that the module is normally communicated with the upper computer terminal when being normally on, indicates that the module is abnormally communicated with the upper computer when being off, indicates that the module is normally communicated with the upper computer terminal when being flickered for 1s and then is off for 1s, and indicates that data exchange is being carried out between the module and the upper computer.

Therefore, the isolation transformer is arranged between the ammeter and the 485 module, and the 485 chip with the capacitance-coupling isolation function is adopted, so that the signal isolation between the 485 communication module and the power end of the ammeter and the isolation between the 485 communication module and the communication port are effectively realized, the contact between a human body contact end and a strong electric end is avoided, and the safety of the ammeter is improved; the arrangement of the open-drain output module can effectively prevent the current of the electric meter from flowing backwards, and the overall stability of the electric meter is improved; the MCU module adopts a chip with the functions of automatically identifying and converting the communication baud rate, so that the baud rate self-adaption of the electric meter can be realized, and the application range of the electric meter is improved; the design of module pilot lamp, the communication state between 485 communication module of being convenient for operating personnel directly perceivedly looking over, ammeter and the host computer has improved convenient operation nature.

While embodiments of the utility model have been shown and described, it will be understood by those skilled in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the utility model, the scope of which is defined by the claims and their equivalents.

Claims

1. The utility model provides a 485 communication module, 485 communication module includes 485 module (2) that link to each other with host computer (1) communication, MCU module (4) with 485 module (2) and ammeter (3) difference communication connection, its characterized in that:

the 485 communication module further comprises a power isolation module (5) which is arranged between the 485 module (2) and the ammeter (3) and used for isolating power supply voltage.

2. The 485 communication module of claim 1, wherein:

the power isolation module (5) comprises an isolation transformer (T1) electrically connected between the ammeter (3) and the 485 module (2).

3. The 485 communication module of claim 2, wherein:

the power isolation module (5) further comprises a voltage stabilizing module (6) arranged between the isolation transformer (T1) and the 485 module (2).

4. The 485 communication module of claim 3, wherein:

the voltage stabilizing module (6) comprises an AZ431 voltage stabilizing tube (N4) which is electrically connected with the isolation transformer (T1) and the 485 module (2).

5. The 485 communication module of claim 3, wherein:

the 485 module (2) comprises an NSi83085 type isolation chip (N2) with a capacitive coupling isolation function, and a power supply end of the isolation chip (N2) is connected with an output end of the voltage stabilizing module (6).

6. The 485 communication module of claim 2, wherein:

the MCU module (4) adopts an FM3313 chip (N1) which can automatically identify and convert 485 communication baud rate.

7. The 485 communication module of claim 2, wherein:

and a leakage opening output module (7) with a backflow prevention function is arranged between the signal output pin (12) of the MCU module (4) and the ammeter (3).

8. The 485 communication module of claim 7, wherein:

the open-drain output module (7) comprises an NPN type triode (V1) with a base electrode connected with a signal output pin (12) of the MCU module (4), a collector electrode electrically connected with the ammeter (3) and a transmitter grounded.

9. The 485 communication module of claim 2, wherein:

the 485 communication module also comprises a module indicator lamp (8) for indicating the communication state of the 485 communication module.

10. The 485 communication module of claim 9, wherein:

the module indicator lamp (8) comprises a red indicator lamp (HL1) used for indicating the communication state between the module and the ammeter (3) and a green indicator lamp (HL2) used for indicating the communication state between the module and the upper computer (1).