CN210954690U

CN210954690U - Distributed intelligent signal acquisition device

Info

Publication number: CN210954690U
Application number: CN201922369708.5U
Authority: CN
Inventors: 马常松; 王麟; 李蕃; 兰鹏
Original assignee: Research Institute of Physical and Chemical Engineering of Nuclear Industry
Current assignee: Research Institute of Physical and Chemical Engineering of Nuclear Industry
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2020-07-07
Anticipated expiration: 2029-12-25

Abstract

The utility model discloses a distributed intelligent signal acquisition device, which comprises a signal conversion module and a signal acquisition module, wherein the signal conversion module is used for converting a current signal into a voltage signal; the AD acquisition module is used for acquiring voltage signals to be detected of the sensor, converting the voltage signals into digital signals and transmitting the digital signals to the main control chip; the constant current source and operational amplifier module converts the temperature change into a voltage signal and transmits the voltage signal to the main control chip for signal acquisition; the main control chip is used for acquiring and processing signals, data instruction communication, information storage and data calculation; a storage module storing device information; the communication module is used for realizing the communication between the main control chip and the upper monitoring; and the power supply module is used for supplying power to the whole device. The utility model CAN carry out on-line detection on the voltage/current signal output by the sensor and the temperature sensor nearby on site, and transmit the acquired data to the monitoring system through the CAN bus for subsequent data analysis; the signal acquisition device has the advantages of small volume, high precision, low cost and fast networking, and capacity expansion can be carried out as required.

Description

Distributed intelligent signal acquisition device

Technical Field

The utility model belongs to sensor output signal measures the field, concretely relates to distributing type intelligence signal pickup assembly.

Background

With the development of industrial automation process, a great number of sensors are distributed in the current industrial field, and the output information of the sensors needs to be collected, and the collected data is uploaded to a monitoring system for analysis, judgment and control. At present, the PLC is generally adopted to collect sensor signals, a measuring system is built quickly, the cost is high, the space occupation is large, the number of field lines is large, loss exists in the signal transmission process, and later maintenance is difficult.

SUMMERY OF THE UTILITY MODEL

The utility model relates to a overcome the shortcoming that exists among the prior art and propose, its purpose provides a distributing type intelligence signal pickup assembly.

The utility model discloses a realize through following technical scheme:

the utility model provides a distributed intelligence signal pickup assembly which characterized in that: the method comprises the following steps:

the signal conversion module is used for converting a current signal to be measured of the sensor into a voltage signal and transmitting the voltage signal to the AD acquisition module;

the AD acquisition module acquires a voltage signal to be detected of the sensor and a signal converted by the signal conversion module and transmits the acquired signal to the main control chip;

the constant current source and operational amplifier module is used for providing a constant current source for the temperature sensor, converting the resistance value of the temperature sensor into the change of voltage and transmitting the change of voltage to the main control chip for signal acquisition;

the main control chip is used for acquiring and processing the received signals, and performing data instruction communication, information storage and data calculation;

the storage module is responsible for the address, the detection threshold value, the communication mode and the voltage and current detection channel configuration information of the storage device;

the communication module is used for realizing the communication between the main control chip and the upper monitoring in a CAN communication mode and finishing the receiving of instructions and the transmission of data;

and the power supply module is used for supplying power to the whole device.

In the above technical solution, the signal conversion module includes a current-voltage converter and a first operational amplifier chip that are connected to each other.

In the technical scheme,

pins

1 and 3 of the current-voltage converter are respectively connected with the negative and positive of an input signal,

pins

2, 5 and 13 are directly grounded, pin 7 is grounded through a capacitor C1,

pins

16 and 4 are respectively connected with a power supply +12V, -12V,

pins

14 and 15 are connected with a pin 3 of an I operational amplifier chip through a resistor R3,

pins

8 and 4 of the I operational amplifier chip are respectively connected with the power supply +12V, -12V, and the pin 3 of the I operational amplifier chip is grounded through resistors R4 and R5; no. 1, No. 2 pins of chip are put to I fortune link to each other through R2, and its No. 2 pin passes through resistance R1 ground connection, and No. 1 pin output signal gets into AD collection module.

In the technical scheme, the signals converted by the constant current source and the operational amplifier module are transmitted to the AD peripheral of the main control chip.

In the above technical solution, the constant current source and the operational amplifier module include a No. ii operational amplifier chip,

pins

1 and 2 of the operational amplifier chip are connected through Pt100, pin 2 is grounded through resistor R6,

pins

3, 4 and 8 are respectively connected to 3.3V, -12V and +12V, pin 5 is grounded through resistors R9 and R10, pin 1 is connected to pin 5 through R9, pin 6 is connected to pin 2 through resistor R8, and pin 7 is connected to pin 6 through R7.

In the above technical solution, the memory module includes a memory chip and adopts an EEPROM manner.

In the above technical solution,

pins

1, 2, 3, 4, and 7 of the memory chip are grounded, pin 8 is connected to 3.3V, pin 6 is connected to 3.3V through a resistor R11, pin 5 is connected to 3.3V through a resistor R12, pin 5 of the memory chip is connected to pin 74 of the main control chip, and pin 6 is connected to pin 75 of the main control chip.

In the above technical solution, the communication module includes a CAN bus driver, and a number i isolation chip and a number ii isolation chip connected thereto respectively.

In the technical scheme, the pin No. 1 of the isolation chip No. I is connected with 3.3V, the pin No. 6 is connected with +5V, the pin No. 5 and the pin No. 6 are connected through a resistor R14, the pin No. 4 is grounded, the pin No. 5 is connected with the pin No. 1 of the CAN bus driver, and the pin No. 3 is connected with the pin No. 176 of the main control chip through a resistor R13; no. 4 pin ground connection of II isolation chip, No. 1 pin connects +5V, No. 6 pin connects 3.3V, lean on resistance R15 to be connected between No. 5 pin and the No. 6 pin, 3 pin passes through resistance 16 and links to each other with the No. 4 pin of CAN bus driver, No. 5 pin is connected with the No. 1 pin of main control chip, No. 2 pin ground connection of CAN bus driver, No. 3 pin connects +5V, No. 8 pin passes through resistance R17 ground connection, 6, No. 7 pin inserts CAN communication network's CANL and CANH respectively.

In the technical scheme, the power supply module comprises a module power supply I, a module power supply II and a module power supply III, wherein a pin 1 of the module power supply I is grounded, a pin 2 is connected with +24V, the

pins

1 and 2 are connected through a capacitor C2, a pin 6 outputs +12V, a pin 8 outputs-12V, a pin 7 is grounded, the

pins

6 and 7 are connected through a capacitor C3, and the

pins

7 and 8 are connected through a capacitor C4; the No. 1 pin of the No. II module power supply is connected with +24V, the No. 2 pin is grounded, the No. 3 pin outputs +5V, the No. 1 pin and the No. 2 pin are connected through a capacitor C5, and the No. 2 pin and the No. 3 pin are connected through a capacitor C6;

pins

5, 6, 11 and 12 of the power supply of the module III are connected with +5V,

pins

3 and 9 are grounded,

pins

17 and 18 output 3.3V, and

pins

23 and 24 output 1.9V.

The utility model has the advantages that:

the utility model provides a distributed intelligent signal acquisition device, which CAN carry out on-line detection on voltage/current signals output by a sensor and a Pt100 temperature sensor nearby on site and transmit acquired data to a monitoring system through a CAN bus for subsequent data analysis; the signal acquisition device has the advantages of small volume, high precision, low cost, fast networking and the like, can expand the capacity as required, and has an industrial application foundation.

Drawings

Fig. 1 is a schematic structural diagram of the distributed intelligent signal acquisition device of the present invention;

fig. 2 is a schematic circuit diagram of a signal conversion module in the distributed intelligent signal acquisition device of the present invention;

fig. 3 is a schematic circuit diagram between the AD acquisition module and the main control chip in the distributed intelligent signal acquisition device of the present invention;

fig. 4 is a schematic circuit diagram of the constant current source and the operational amplifier module in the distributed intelligent signal acquisition device of the present invention;

fig. 5 is a schematic circuit diagram of a storage module in the distributed intelligent signal acquisition device of the present invention;

fig. 6 is a schematic circuit diagram of a communication module in the distributed intelligent signal acquisition device of the present invention;

fig. 7 is a schematic circuit diagram of a power supply module in the distributed intelligent signal acquisition device according to the present invention;

fig. 8 is a flow chart of the acquisition method of the distributed intelligent signal acquisition device of the present invention;

fig. 9 is a flow chart of the communication method of the distributed intelligent signal acquisition device of the present invention.

Wherein:

1 signal conversion module 2AD acquisition module

3 constant current source and operational amplifier module 4 main control chip

5 storage module 6 communication module

7 power supply module 8 current-voltage converter

No. 9I operational amplifier chip No. 10 III module power supply

11 II operational amplifier chip 12 storage chip

No. 13I isolation chip and No. 14 II isolation chip

16I model power supply of 15CAN bus driver

17 # II module power supply.

For a person skilled in the art, other relevant figures can be obtained from the above figures without inventive effort.

Detailed Description

In order to make the technical solution of the present invention better understood by those skilled in the art, the technical solution of the distributed intelligent signal acquisition apparatus of the present invention is further described below by referring to the drawings of the specification and the specific implementation manner.

Example 1

As shown in fig. 1, a distributed intelligent signal acquisition apparatus includes:

the signal conversion module 1 is used for converting a current signal to be measured of the sensor into a voltage signal and transmitting the voltage signal to the AD acquisition module 2;

the AD acquisition module 2 is used for acquiring a voltage signal to be detected of the sensor and a signal converted by the signal conversion module 1 and transmitting the acquired signal to the main control chip 4;

the constant current source and operational amplifier module 3 converts the temperature change of the sensor into a voltage signal and transmits the voltage signal to the AD peripheral equipment of the main control chip 4 for signal acquisition;

the main control chip 4 is used for collecting and processing the received signals, and performing data instruction communication, information storage and data calculation;

the storage module 5 is responsible for storing the address, the detection threshold value, the communication mode and the configuration information of the voltage and current detection channel of the device;

the communication module 6 is used for realizing the communication between the main control chip 4 and the upper monitoring in a CAN communication mode; receiving an upper monitoring command, and uploading detected data or error information to an upper monitoring system;

and a power supply module 7 for supplying power to the whole device.

In this embodiment, the 8 paths of voltage/current signal channels to be tested can be configured in different proportions as required, the range of the voltage signal to be tested is 0V- +10V, and the voltage signal directly enters the AD acquisition module 2 for signal acquisition. The range of the current signal to be measured is 4-20 mA, the current signal is converted into a 0- +10V signal through the signal conversion module 1 and then enters the AD acquisition module 2 for signal acquisition. The signal of the Pt00 sensor to be measured is processed by the constant current source and the operational amplifier module 3, the temperature change is converted into 0- +3.3V signal, and the signal enters the AD peripheral of the main control chip 4 for signal acquisition. The data detected by the main control chip 4 is uploaded to an upper monitoring system through the communication module 6. Each signal acquisition device has a unique identification address, and the identification information of the device is stored in the storage module 5 and can be read and modified online. And simultaneously storing the detection threshold value of the signal, the communication mode and the configuration information of the voltage/current detection channel. The power supply module 7 is responsible for supplying power to the various modules.

As shown in fig. 2, the signal conversion module 1 is mainly responsible for converting a current signal with an output current signal of 4-20 mA of an industrial field sensor into a voltage signal for signal acquisition in the AD acquisition module for the conversion of the amplitude of the output current signal. Firstly, the voltage signals are converted into 0-5V voltage signals through a precise current-voltage converter 8 (the model is RCV420), and then the voltage signals are converted into 0-10V voltage signals through a I operational amplifier chip 9 (the model is AD822) and enter an AD acquisition module.

Pins

1 and 3 of the current-voltage converter 8 are respectively connected with the negative and positive of an input signal, pins 2, 5 and 13 are directly grounded, and pin 7 is connected with the ground through a capacitor C1. 16. The 4 pins are respectively connected with +12V and-12V of a power supply, and the 14 and 15 pins are connected with the 3 pins of the I-type operational amplifier chip 9 through a resistor R3. The 8 and 4 pins of the I operational amplifier chip 9 are respectively connected with a power supply +12V and-12V, the 3 pins of the I operational amplifier chip 9 are connected with the ground through resistors R4 and R5, the 1 and 2 pins of the I operational amplifier chip 9 are connected with the ground through R2, the 2 pin is connected with the ground through a resistor R1, and the 1 pin outputs signals to the AD acquisition module 2.

As shown in fig. 3, the AD acquisition module 2 is mainly responsible for converting an input voltage/current analog signal into a digital signal, and then storing the data in the main control chip 4 for waiting for processing, and the AD acquisition module 2 selects an a/D conversion chip with the model number ADs 8568.

Pins 16-23 and 26-33 of the AD acquisition module 2 are respectively connected with pins 136-122, 116 and 115 of the main control chip 4, pins 8-13 and 34-41 are respectively connected with pins 18-21, 2, 6, 175, 7, 174, 11-13, 16 and 17 of the main control chip 4, pin 1 is connected with-12V, and pin 48 is connected with + 12V.

The main control chip 4 selects TMS320F28335 of TI company, and is mainly responsible for controlling AD chip acquisition, Pt00 signal acquisition and processing, data instruction communication, information storage and data calculation.

As shown in fig. 4, the constant current source and operational amplifier module 3 detects the Pt100 by a constant current source method, converts the resistance change of the Pt100 into a voltage signal, and performs signal acquisition by the AD peripheral of the main control chip 4. The constant current source is generated through one path of operational amplifier of the operational amplifier chip II 11, and the other path of operational amplifier is used for amplifying the voltage drop signal of the Pt100 to a voltage signal of 0-3.3V and entering the AD peripheral of the main control chip 4.

The constant current source and operational amplifier module 3 is responsible for providing a constant current source for the Pt100 and converting the resistance value of the Pt100 into the change of voltage. The connection relationship is as follows: the constant current source and operational amplifier module 3 comprises a No. II operational amplifier chip 11, pins 1 and 2 of the operational amplifier chip are connected through Pt100, pin 2 is grounded through a resistor R6, pins 3, 4 and 8 are respectively connected with 3.3V, -12V and +12V, pin 5 is grounded through resistors R9 and R10, pin 1 and pin 5 are connected through R9, pin 6 and pin 2 are connected through a resistor R8, and pin 7 and pin 6 are connected through R7. According to the concept of virtual earth and virtual break of the operational amplifier, the virtual frame circuit of the operational amplifier chip II 11 is equivalent to a constant current source flowing through Pt100, the voltage drop on the Pt100 is only related to the change of the resistance value of the chip, and the amplification factor can be controlled by adjusting R7, R8, R9 and R10.

As shown in fig. 5, the storage module 5 is responsible for storing the device of the present invention, which is used for storing the address, the detection threshold and the abnormal operation state measurement parameter, the communication mode and the configuration information of the voltage and current detection channel. The memory module 5 adopts an EEPROM mode, and the memory module 5 comprises a memory chip 12 with the model number of AT24C1024 and resistors R11 and R12.

Pins

1, 2, 3, 4 and 7 of the memory chip 12 are grounded, pins 8 are connected with 3.3V, pins 6 are connected with 3.3V through a resistor R11, pins 5 are connected with 3.3V through a resistor R12, pins 5 and pins 6 of the memory chip 12 are connected with pins 74 and pins 6 of the main control chip 4 respectively.

The utility model discloses the device adopts CAN communication mode to the external communication. As shown in fig. 6, the communication module 6 is responsible for receiving the upper monitoring command and uploading the detected data or error information to the upper monitoring system through the communication module.

The communication module 6 comprises a CAN bus driver 15 with a model of PCA82C250, and a first isolation chip 13 and a second isolation chip 14 which are connected with the CAN bus driver and have models of TLP 2361.

The CAN bus driver 15 provides an interface between a CAN controller and a physical bus, is physically connected with a main control chip through pins TXD and RXD, and is hung on the CAN communication bus through transceiving ends CANH and CANL.

The No. 1 pin of the No. I isolation chip 13 is connected with 3.3V, the No. 6 pin is connected with +5V, the No. 5 pin is connected with the No. 6 pin through a resistor R14, the No. 4 pin is grounded, the No. 5 pin is connected with the No. 1 pin of the CAN bus driver 15, and the No. 3 pin is connected with the No. 176 pin of the main control chip 4 through a resistor R13; no. 4 pin ground connection of II isolation chip 14, No. 1 pin connects +5V, No. 6 pin connects 3.3V, lean on resistance R15 to be connected between No. 5 pin and the No. 6 pin, 3 pin passes through resistance 16 and links to each other with No. 4 pin of CAN bus driver 15, No. 5 pin is connected with No. 1 pin of main control chip 4, No. 2 pin ground connection of CAN bus driver 15, No. 3 pin connects +5V, No. 8 pin passes through resistance R17 ground connection, 6, No. 7 pin inserts CAN communication network's CANL and CANH respectively.

For a high-precision signal acquisition and processing system, the precision of a power supply module directly influences the precision of an acquired signal. As shown in fig. 7, the power supply module 7 supplies power to the respective modules. The power supply used by the utility model comprises 12V, +5V, +3.3V, + 1.9V. The device adopts +24V power supply, wherein +/-12V is obtained by converting an input power supply of +24V through a module power supply I16 with the model number WRA2412S, and +5V is obtained by converting an input power supply of +24V through a module power supply K7805 II 17. Considering the power consumption of the 3.3V and 1.9V circuit parts, a model III module power supply 10 of TI company, the model number of TPS767D301, is adopted, the output voltage of the power supply is 3.3V all the way, 1.9V all the way, and the maximum output current of each power supply is 1 ampere.

The No. 1 pin of the No. I module power supply 16 is grounded, the No. 2 pin is connected with +24V, the No. 1 and the No. 2 pins are connected through a capacitor C2, the No. 6 pin outputs +12V, the No. 8 pin outputs-12V, the No. 7 pin is grounded, the No. 6 and the No. 7 pins are connected through a capacitor C3, and the No. 7 and the No. 8 pins are connected through a capacitor C4; pin 1 of the module power supply 17 No. II is connected with +24V, pin 2 is grounded, pin 3 outputs +5V, pins 1 and 2 are connected through a capacitor C5, and pins 2 and 3 are connected through a capacitor C6; pins 5, 6, 11 and 12 of the module power supply 10 No. III are connected with +5V, pins 3 and 9 are grounded, pins 17 and 18 output 3.3V, and pins 23 and 24 output 1.9V.

Example 2

The utility model discloses a signal acquisition method, as shown in FIG. 8, concrete step is as follows:

s1: start of

S2: and powering on and initializing the device. After the device is started, the main control chip 4 is initialized with each peripheral function module.

S3: and reading device address and threshold information. And reading the address and threshold information stored in the device.

S4: voltage/current channel information is read. The distribution proportion of the number of voltage signal detection channels and the number of current signal detection channels is read according to the field condition for 8 channels.

S5: if yes, the process proceeds to S6, and if no, the process proceeds to S7.

S6: the devices communicate. And the device is communicated with an upper monitoring system.

S7: and detecting a voltage/current signal.

S8: and detecting Pt100 signals. The change of the temperature is expressed as the change of the resistance value on the Pt100, and the corresponding temperature value is obtained by detecting the voltage values at two ends of the Pt100 and looking up a table.

The device and the upper monitoring system adopt CAN bus communication, and the device receives corresponding instructions according to the set address and executes corresponding operation after analysis. The detection of the communication command by the device is to perform an inquiry at the timer interrupt, as shown in fig. 9, the specific steps of the device communication in step S6 are as follows:

s9: start of

S10: and judging whether the communication response time is exceeded. If the excess is exceeded, the process proceeds to S11, and if the excess is not exceeded, the process proceeds to S12.

S11: and if the communication response time is exceeded, alarming to display abnormal communication.

S12: and judging whether the address of the device in the instruction is consistent with that of the device. If the address in the command does not match the own device address, the process proceeds to S18, and if the address matches, the process proceeds to S13.

S13: it is determined whether the command is a data write command or a read command. The data write command proceeds to S14, and the data read command proceeds to S16.

S14: and acquiring and analyzing communication data.

S15: the data write operation is performed according to the instruction.

S16: and acquiring and analyzing communication data.

S17: data read operations are performed according to the instructions.

S18: and (6) ending.

The utility model provides a distributing type intelligence signal pickup assembly carries out the online distributed measurement that detects to sensor output signal, mainly is the sensor signal that is voltage or electric current to the output form to and Pt100 temperature sensor carries out the on-line measuring. The utility model has high performance-price ratio, and can realize the detection of 8 voltage/current signals and the detection of 4 Pt100 sensor signals; the number of voltage and current signal detection channels can be configured according to the field requirement, and the method has strong adaptability and expansibility; the address of the device in the communication network can be stored, the device identification address can be modified and inquired on line, and the universality and interchangeability of the device are improved.

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The applicant states that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and those skilled in the art should understand that any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present invention are within the protection scope and the disclosure scope of the present invention.

Claims

1. The utility model provides a distributed intelligence signal pickup assembly which characterized in that: the method comprises the following steps:

the signal conversion module (1) converts a current signal to be measured of the sensor into a voltage signal and transmits the voltage signal to the AD acquisition module (2);

the AD acquisition module (2) is used for acquiring a voltage signal to be detected of the sensor and a signal converted by the signal conversion module (1) and transmitting the acquired signal to the main control chip (4);

the constant current source and operational amplifier module (3) is used for providing a constant current source for the temperature sensor, converting the resistance value of the temperature sensor into the change of voltage and transmitting the change of voltage to the main control chip (4) for signal acquisition;

the main control chip (4) is used for acquiring and processing the received signals, and performing data instruction communication, information storage and data calculation;

the storage module (5) is responsible for the address, the detection threshold value, the communication mode and the voltage and current detection channel configuration information of the storage device;

the communication module (6) is used for realizing the communication between the main control chip (4) and the upper monitoring in a CAN communication mode and completing the instruction receiving and data transmission;

and the power supply module (7) is used for supplying power to the whole device.

2. A distributed intelligent signal acquisition apparatus as claimed in claim 1, wherein: the signal conversion module (1) comprises a current-voltage converter (8) and a No. I operational amplifier chip (9) which are connected with each other.

3. A distributed intelligent signal acquisition apparatus as claimed in claim 2, wherein: pins 1 and 3 of the current-voltage converter (8) are respectively connected with the negative and positive of an input signal, pins 2, 5 and 13 are directly grounded, pin 7 is grounded through a capacitor C1, pins 16 and 4 are respectively connected with a power supply +12V, -12V, pins 14 and 15 are connected with a pin 3 of the I operational amplifier chip (9) through a resistor R3, pins 8 and 4 of the I operational amplifier chip (9) are respectively connected with the power supply +12V, -12V, and a pin 3 of the I operational amplifier chip (9) is grounded through resistors R4 and R5; no. 1 and No. 2 pins of the No. I operational amplifier chip (9) are connected through R2, the No. 2 pin is grounded through a resistor R1, and the No. 1 pin outputs signals to an AD acquisition module (2).

4. A distributed intelligent signal acquisition apparatus as claimed in claim 1, wherein: and the signals converted by the constant current source and operational amplifier module (3) are transmitted to an AD peripheral of the main control chip (4).

5. A distributed intelligent signal acquisition apparatus as claimed in claim 1, wherein: the constant current source and operational amplifier module (3) comprises a No. II operational amplifier chip (11), pins 1 and 2 of the constant current source and operational amplifier chip are connected through Pt100, a pin 2 is grounded through a resistor R6, pins 3, 4 and 8 are respectively connected with 3.3V, -12V and +12V, a pin 5 is grounded through resistors R9 and R10, a pin 1 is connected with a pin 5 through R9, a pin 6 is connected with a pin 2 through a resistor R8, and a pin 7 is connected with a pin 6 through R7.

6. A distributed intelligent signal acquisition apparatus as claimed in claim 1, wherein: the memory module (5) comprises a memory chip (12) and adopts an EEPROM mode.

7. A distributed intelligent signal acquisition apparatus as claimed in claim 6, wherein: no. 1, 2, 3, 4 and 7 pins of the memory chip (12) are grounded, No. 8 pin is connected with 3.3V, No. 6 pin is connected with 3.3V through a resistor R11, No. 5 pin is connected with 3.3V through a resistor R12, No. 5 pin of the memory chip (12) is connected with No. 74 pin of the main control chip (4), and No. 6 pin is connected with No. 75 pin of the main control chip (4).

8. A distributed intelligent signal acquisition apparatus as claimed in claim 1, wherein: the communication module (6) comprises a CAN bus driver (15), and a No. I isolation chip (13) and a No. II isolation chip (14) which are respectively connected with the CAN bus driver.

9. A distributed intelligent signal acquisition apparatus as claimed in claim 8, wherein: the No. 1 pin of the No. I isolation chip (13) is connected with 3.3V, the No. 6 pin is connected with +5V, the No. 5 pin is connected with the No. 6 pin through a resistor R14, the No. 4 pin is grounded, the No. 5 pin is connected with the No. 1 pin of the CAN bus driver (15), and the No. 3 pin is connected with the No. 176 pin of the main control chip (4) through a resistor R13; no. 4 pin ground connection of II isolation chip (14), No. 1 pin connects +5V, No. 6 pin connects 3.3V, lean on resistance R15 to be connected between No. 5 pin and the No. 6 pin, 3 pin passes through resistance 16 and links to each other with No. 4 pin of CAN bus driver (15), No. 5 pin is connected with No. 1 pin of main control chip (4), No. 2 pin ground connection of CAN bus driver (15), No. 3 pin connects +5V, No. 8 pin passes through resistance R17 ground connection, 6, No. 7 pin inserts CAN communication network's CANL and CANH respectively.

10. A distributed intelligent signal acquisition apparatus as claimed in claim 1, wherein: the power supply module (7) comprises a module power supply I (16), a module power supply II (17) and a module power supply III (10), wherein a pin 1 of the module power supply I (16) is grounded, a pin 2 is connected with +24V, pins 1 and 2 are connected through a capacitor C2, a pin 6 is output with +12V, a pin 8 is output with-12V, a pin 7 is grounded, pins 6 and 7 are connected through a capacitor C3, and pins 7 and 8 are connected through a capacitor C4; no. 1 pin of the No. II module power supply (17) is connected with +24V, No. 2 pin is grounded, No. 3 pin outputs +5V, No. 1 and No. 2 pins are connected through a capacitor C5, and No. 2 and No. 3 pins are connected through a capacitor C6; pins 5, 6, 11 and 12 of the module power supply (10) III are connected with +5V, pins 3 and 9 are grounded, and pins 17 and 18 output pins 3.3V and pins 23 and 24 output pins 1.9V.