An environmental monitoring host

Abstract

The utility model discloses an environmental monitoring host computer, including main control unit, with the dew point / smoke compound sensor interface of main control unit connection, PT100 high accuracy temperature measurement module and RS485 isolation communication circuit and for this environmental monitoring host computer provides the multistage anti -jamming power module of power supply, the utility model discloses through multistage isolation power supply design, hardware level anti -jamming processing (optical coupling / RC / TVS) of key signal, high accuracy constant current source temperature measurement and compact interface integration, solved the problem that traditional monitoring equipment is vulnerable to interference, precision is insufficient, reliability is poor under the industrial environment.

Description

Technical Field

[0001] This utility model relates to the technical field, and more specifically, to an environmental monitoring host. Background Technology

[0002] Currently, in scenarios with strong electromagnetic interference, such as power and chemical industries, environmental monitoring hosts suffer from data acquisition instability and short system lifespan when collecting ambient temperature data, resulting in insufficient product accuracy and poor reliability. Utility Model Content

[0003] The purpose of this invention is to provide an environmental monitoring host to solve the problems existing in the prior art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] An environmental monitoring host includes a main control unit, a dew point / smoke composite sensor interface, a PT100 high-precision temperature measurement module and an RS485 isolated communication circuit connected to the main control unit, and a multi-level anti-interference power supply module that provides power to the environmental monitoring host.

[0006] Furthermore, the main control unit is an STM32F series microcontroller, which is connected to an 8MHz crystal oscillator X1, an SWD debugging interface P6, and a BOOT configuration circuit.

[0007] Furthermore, the multi-level anti-interference power supply module includes an AC / DC converter U12, an AC / DC converter U13, and a DC / DC converter U14. The AC / DC converter U12 is model HLK-5M05, its AC input terminal is connected to a varistor R45, and its output is 5VDC, which is filtered by a π-type filter. The DC / DC converter U14 is model AMS1117-3.3, its output is 3.3VDC, which is filtered by a capacitor bank. The AC / DC converter U13 is model HLK-PM01, its output is 24VDC, and it provides external power to the smoke sensor.

[0008] Furthermore, the dew point / smoke composite sensor interface includes a PT100 temperature measurement port P3 and a 4-20mA input interface P1. The PT100 temperature measurement port P3 is connected to a constant current source circuit, and the 4-20mA input interface P1 is connected to an RC filter circuit.

[0009] Furthermore, the RS485 isolated communication circuit uses an SP3485 chip.

[0010] Compared with the prior art, the advantages of this utility model are as follows: This utility model solves the problems of traditional monitoring equipment being susceptible to interference, having insufficient accuracy, and having poor reliability in industrial environments by using a multi-level isolated power supply design, hardware-level anti-interference processing for key signals (optical coupler / RC / TVS), high-precision constant current source temperature measurement, and compact interface integration. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the present invention;

[0013] Figure 2 This is the circuit diagram of the main control unit in this utility model;

[0014] Figure 3 This is the circuit diagram of the multi-level anti-interference power supply module in this utility model;

[0015] Figure 4 This is a circuit diagram of the dew point / smoke composite sensor interface in this utility model;

[0016] Figure 5 This is a circuit diagram of the PT100 interface circuit in this utility model;

[0017] Figure 6 This is the circuit diagram of the 4-20mA input circuit in this utility model;

[0018] Figure 7 This is a circuit diagram of the relay drive circuit in this utility model;

[0019] Figure 8 This is a circuit diagram of the RS485 isolated communication circuit in this utility model;

[0020] Figure 9 This is a circuit diagram of the switch input circuit in this utility model;

[0021] Figure 10 This is a circuit diagram of the status indicator circuit in this utility model;

[0022] Figure 11 This is a circuit diagram of the memory expansion circuit in this utility model;

[0023] Figure 12 This is the circuit diagram of the clock circuit in this utility model;

[0024] Figure 13 This is the circuit diagram of the reset circuit in this utility model. Detailed Implementation

[0025] The following detailed description of further embodiments of the present invention, in conjunction with the accompanying drawings, will make the advantages and features of the present invention more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0026] See Figure 1 As shown, this utility model provides an environmental monitoring host, including a main control unit, a dew point / smoke composite sensor interface, a PT100 high-precision temperature measurement module and an RS485 isolated communication circuit connected to the main control unit, and a multi-level anti-interference power supply module that provides power to the environmental monitoring host.

[0027] See Figure 2 As shown, the main control unit is an STM32F series microcontroller, which is connected to an 8MHz crystal oscillator X1, an SWD debugging interface P6, and a BOOT configuration circuit (composed of resistors R38 and R39).

[0028] See Figure 3 As shown, the multi-level anti-interference power supply module includes an AC / DC converter U12 and a DC / DC converter U14.

[0029] The AC / DC converter U12 is model HLK-5M05. Its AC input terminal is connected to a varistor R45, and its output is 5VDC, which is filtered by a π-type filter (composed of capacitor C28 and resistor R48).

[0030] In this embodiment, the EMC protection of the power module includes: parallel varistors R45 and R46 (10D471K) at the AC input terminal, TVS diodes D2 (M7-SMA) and D3 (30CA) on the DC side, and common mode inductors L1 and L2.

[0031] The DC / DC converter U14 is model AMS1117-3.3, and its output is 3.3VDC, which is filtered by a capacitor bank (composed of capacitors C29-C32).

[0032] See Figures 4-6 As shown, the dew point / smoke composite sensor interface includes a PT100 temperature measurement port P3 and a 4-20mA input interface P1.

[0033] The PT100 temperature measurement port P3 is connected to the PT100 interface circuit, and the 4-20mA input interface P1 is connected to the 4-20mA input circuit.

[0034] In this embodiment, the PT100 interface circuit includes: a constant current source load consisting of precision resistors R1 and R2 (4.7kΩ), an operational amplifier feedback loop resistor R19, a resistor R23 (100kΩ), and a noise suppression capacitor C15 (0.1μF).

[0035] In this embodiment, the 4-20mA input circuit includes: an input protection diode D1 (6.8CA), a filter capacitor C14 (2.2nF) and a current-limiting resistor R18 (10kΩ) connected in parallel, and a signal conversion resistor R17 (4.7kΩ).

[0036] See Figure 7 As shown, the relay drive circuit includes: ULN2003 Darlington array (U3, U4) driving the relay group, a parallel RC snubber circuit for the relay coil (R20 / R16 620Ω + C13 / C14 2.2nF), and freewheeling diodes D4-D6 (6.8CA).

[0037] See Figure 8 As shown, the RS485 isolation communication circuit uses an SP3485 chip, which forms an RS485 bus. The control signals (RE / DE) are isolated via optocouplers U5 and U6, which are TLP785 chips.

[0038] Specifically, the RS485 isolated communication circuit includes control signal optocoupler isolators U5 and U6 (TLP785), bus terminal TVS transistor D1 (6.8CA), and impedance matching resistors R4 and R7 (4.7kΩ).

[0039] See Figure 9 As shown, the digital input circuit includes 7 independent buttons, including: pull-up resistors R27-R33 (10kΩ), hardware debouncing capacitors C17-C23 (0.1μF), and ESD protection components R34-R37 (1kΩ).

[0040] See Figure 10 As shown, the status indicator circuit includes: LED1-LED6 connected to the MCU through current-limiting resistors R40-R44 (1kΩ), and running indicator lights LD1 and LD2 controlled by transistor driver circuits (Q1, Q2).

[0041] See Figure 11 As shown, the memory expansion circuit includes: I 2 C-interface EEPROM chip U7 (AT24C16C), pull-up resistors R35 and R36 (4.7kΩ).

[0042] See Figure 12 As shown, the clock circuit consists of a crystal oscillator X1 (8MHz), load capacitors C26 and C27 (22pF), and a matching resistor R41 (10kΩ).

[0043] See Figure 9 , Figure 13 As shown, the reset circuit includes a reset button S1, a filter capacitor C25 (0.1μF), and a pull-up resistor R39 (10kΩ).

[0044] External interfaces include dew point sensor interfaces (P0*101-P0*202), relay output terminals (JDQ11-JDQ25), and debugging interfaces (…). Figure 11 The P6 in the middle uses a 4-pin Header to connect to SWDIO / SWCLK.

[0045] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, the patent owner may make various modifications or alterations within the scope of the appended claims, as long as they do not exceed the protection scope described in the claims of the present invention, they shall all be within the protection scope of the present invention.

Claims

1. An environmental monitoring host, characterized in that, It includes a main control unit, a dew point / smoke composite sensor interface connected to the main control unit, a PT100 high-precision temperature measurement module and an RS485 isolated communication circuit, as well as a multi-level anti-interference power supply module that provides power to the environmental monitoring host.

2. The environmental monitoring host according to claim 1, characterized in that, The main control unit is an STM32F series microcontroller, which is connected to an 8MHz crystal oscillator X1, an SWD debugging interface P6, and a BOOT configuration circuit.

3. The environmental monitoring host according to claim 1, characterized in that, The multi-level anti-interference power supply module includes an AC / DC converter U12, an AC / DC converter U13, and a DC / DC converter U14. The AC / DC converter U12 is model HLK-5M05, its AC input terminal is connected to a varistor R45, and its output is 5VDC, which is filtered by a π-type filter. The DC / DC converter U14 is model AMS1117-3.3, its output is 3.3VDC, which is filtered by a capacitor bank. The AC / DC converter U13 is model HLK-PM01, its output is 24VDC, and it provides external power to the smoke sensor.

4. The environmental monitoring host according to claim 1, characterized in that, The dew point / smoke composite sensor interface includes a PT100 temperature measurement port P3 and a 4-20mA input interface P1. The PT100 temperature measurement port P3 is connected to the PT100 interface circuit, and the 4-20mA input interface P1 is connected to the 4-20mA input circuit.

5. The environmental monitoring host according to claim 1, characterized in that, The RS485 isolated communication circuit uses an SP3485 chip.

Images