CN201413570Y - Data acquisition and transmission instrument with photoelectric isolation function - Google Patents

Abstract

The utility model discloses a data acquisition and transmission instrument with photoelectric isolation function, which comprises a microcontroller MCU, an analog quantity access interface, a digital quantity access interface, a storage unit and a real-time clock circuit respectively connected with the microcontroller MCU , and the power supply for supplying power to each power unit, the number of the analog input interface and the digital input interface are multiple, and the analog input interface is successively passed through the A/D conversion circuit and the signal isolation circuit. Connected to the microcontroller MCU, the digital input interface is connected to the microcontroller MCU through the serial communication module, the signal isolation circuit 2 and the serial port expansion unit in turn; the power supply is A/D conversion circuit after the DC/DC power isolation module And serial communication module power supply. The utility model has the advantages of reasonable structure, small size, fast response speed and strong impact resistance, and can effectively solve various signal isolation problems in the use process of the data acquisition instrument.

Description

Data acquisition and transmission instrument with photoelectric isolation function

technical field

The utility model relates to a data acquisition and transmission instrument, in particular to a data acquisition and transmission instrument with photoelectric isolation function.

Background technique

At present, most of the data acquisition instruments used in the market are integrated with analog input interface and digital input interface at the same time. In order to ensure the safety of the equipment, the signal part is isolated; the power part is not isolated from the system power supply. Since the data acquisition instrument is generally used in industrial places, its digital interface is connected to the on-site instrument, so the high-voltage environment in the industrial place may affect the response speed, service life, and anti-interference ability of the data acquisition instrument. Certainly affected.

Utility model content

The technical problem to be solved by the utility model is to provide a data acquisition and transmission instrument with photoelectric isolation function in view of the deficiencies in the above-mentioned prior art, which has a reasonable structure, small size, fast response speed, strong impact resistance, and can Effectively solve various signal isolation problems in the use of data loggers.

In order to solve the above technical problems, the technical solution adopted by the utility model is: a data acquisition and transmission instrument with photoelectric isolation function, including a microcontroller MCU, an analog input interface, a digital input interface, and a microcontroller respectively The storage unit connected to the MCU and the real-time clock circuit, and the power supply for supplying power to each power consumption unit, the number of the analog input interface and the digital input interface are multiple, and it is characterized in that: the analog The quantity access interface is connected to the microcontroller MCU after the A/D conversion circuit and the signal isolation circuit one in turn, and the digital quantity access interface is connected to the microcontroller MCU after the serial port communication module, the signal isolation circuit two and the serial port expansion unit in turn ; The power supply supplies power to the A/D conversion circuit and the serial port communication module after passing through the DC/DC power isolation module.

The serial port communication module is an RS232 chip and/or an RS485 chip.

The first signal isolation circuit is a PS2801 photoelectric coupling circuit.

The second signal isolation circuit is a HCPL-600 high-speed photoelectric coupling circuit.

Compared with the prior art, the utility model has the following advantages: 1. The design is reasonable, and has the advantages of fast response speed, long service life, small volume and impact resistance. 2. The use effect is good. Its isolation circuit is integrated with power isolation circuit and signal isolation circuit, which can effectively suppress system noise and eliminate ground loop interference. In addition, in the actual use process, in order to prevent the damage caused by the high voltage to the equipment of the data acquisition instrument, a high-voltage capacitor with a capacity of 3KV is connected to the signal input end of the data acquisition instrument in parallel to ensure the reliable operation of the equipment and the safety of the operator. personal safety. 3. The utility model completely isolates the transmitted digital signal from the power supply used in the digital transmission part; at the same time, the analog signal is transferred to the digital signal of the microcontroller MCU after being converted by the A/D conversion circuit. The signal and the power supply are also separately isolated; in this way, the analog part is completely isolated from the digital part, thereby reducing the interference of the analog part on the digital part. Through practical application, after adopting the isolation circuit described in the utility model, the stable operation of the data acquisition and transmission instrument can be guaranteed, and the use time of the equipment can be prolonged. To sum up, the utility model has reasonable structure, small size, fast response speed and strong impact resistance, and can effectively solve various signal isolation problems during the use of the data acquisition instrument.

The technical solutions of the present utility model will be further described in detail through the drawings and embodiments below.

Description of drawings

Fig. 1 is the circuit block diagram of the utility model.

Explanation of reference signs:

1-microcontroller MCU; 2-analog access interface; 3-digital access interface;

4-storage unit; 5-real-time clock circuit; 6-power supply;

7-A/D conversion circuit; 8-Signal isolation circuit one; 9-Serial communication module;

9-1-RS232 chip; 9-2-RS485 chip; 10-signal isolation circuit two;

11-serial port expansion unit; 12-DC/DC power isolation module.

Detailed ways

As shown in Figure 1, the utility model comprises microcontroller MCU1, analog quantity access interface 2, digital quantity access interface 3, storage unit 4 and real-time clock circuit 5 connected with microcontroller MCU1 respectively, and to each The power supply 6 for power supply by the electric unit. There are multiple analog quantity access interfaces 2 and digital quantity access interfaces 3 . The analog quantity access interface 2 is connected to the microcontroller MCU1 after the A/D conversion circuit 7 and the signal isolation circuit one 8 successively, and the digital quantity access interface 3 is successively passed through the serial port communication module 9, the signal isolation circuit two 10 and the The serial port expansion unit 11 is followed by the microcontroller MCU1; the power supply 6 supplies power to the A/D conversion circuit 7 and the serial port communication module 9 respectively through the DC/DC power isolation module 12 .

The serial port communication module 9 is an RS232 chip 9-1 and/or an RS485 chip 9-2, and the signal isolation circuit one 8 is a PS2801 photoelectric coupling circuit. The second signal isolation circuit 10 is an HCPL-600 signal isolation circuit.

In this embodiment, the number of the analog input interface 2 is three, and the signals connected to it are specifically the on-site voltage and current signals collected by relevant sensors, and the three analog input signals are converted by A/D After the circuit 7 is converted into a digital signal, it communicates with the microcontroller MCU1 in the form of an SPI bus, and the communication between the A/D conversion circuit 7 and the microcontroller MCU1 uses a PS2801 photoelectric coupling circuit to realize signal isolation; The DC/DC power isolation module 12 effectively isolates the power supply 6 and the A/D conversion circuit 7 , and realizes the independent power supply of the A/D conversion circuit 7 .

The number of said digital quantity access interface 3 is five, specifically including 4-way RS232 communication module and 1-way RS485 communication module, wherein the 4-way RS232 communication module is composed of 2 groups of RS232 chips, and the RS485 communication module is composed of a group of RS485 chips , each group of RS232 chips and RS485 chips and the power supply 6 are isolated through the DC/DC power isolation module 12, which realizes the independent power supply of each group of chips, and also avoids the gap between each group of chips when connecting devices. mutual interference. In addition, because the digital signal requires a high transmission rate in use, ordinary optocoupler isolation can only achieve signal isolation, but cannot meet high-speed applications. The utility model adopts a high-speed optocoupler circuit, which realizes In addition to signal isolation, it can also meet the maximum transmission rate of 19200bit/S.

The above are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any simple modifications, changes and equivalent structural changes made to the above embodiments according to the technical essence of the present utility model still belong to Within the scope of protection of the technical solution of the utility model.

Claims (4)

1. instrument is transmitted in the data acquisition with photoelectricity isolation features, comprise microcontroller MCU (1), analog quantity access interface (2), digital quantity access interface (3), storage unit (4) and the real time clock circuit (5) that joins with microcontroller MCU (1) respectively, and the power supply (6) that each power unit is powered, the quantity of described analog quantity access interface (2) and digital quantity access interface (3) is a plurality of, it is characterized in that: described analog quantity access interface (2) meets microcontroller MCU (1) successively after A/D change-over circuit (7) and signal isolation circuit one (8), and described digital quantity access interface (3) is successively through serial communication module (9), meet microcontroller MCU (1) behind signal isolation circuit two (10) and serial ports expansion unit (11); Described power supply (6) is respectively A/D change-over circuit (7) and serial communication module (9) power supply after DC/DC power isolation module (12).

2. according to the described data acquisition transmission instrument with photoelectricity isolation features of claim 1, it is characterized in that: described serial communication module (9) is RS232 chip (9-1) and/or RS485 chip (9-2).

3. according to claim 1 or 2 described data acquisition transmission instrument with photoelectricity isolation features, it is characterized in that: described signal isolation circuit one (8) is PS2801 photoelectricity coupled circuit.

4. according to claim 1 or 2 described data acquisition transmission instrument with photoelectricity isolation features, it is characterized in that: described signal isolation circuit two (10) is HCPL-600 high speed optoelectronic coupled circuit.