CN203298804U - Environmental temperature/humidity wireless monitoring measuring instrument - Google Patents

Abstract

The utility model relates to an environmental temperature and humidity wireless monitoring and measuring instrument, which is composed of a main unit of the environmental temperature and humidity wireless monitoring and measuring instrument and a wireless monitoring module. , signal output port, adjustment knob and function selection switch, the host of the measuring instrument has a wireless receiving circuit. The wireless monitoring module is provided with a measurement switch button and a rotatable transmitting antenna, and the wireless monitoring module has a temperature and humidity sensor and a wireless transmitting circuit. At the same time, the measuring instrument can be connected with a computer to complete the analysis, calculation and processing of data. The measuring instrument can realize the real-time monitoring of the temperature and humidity of the test environment, multi-point wireless measurement and other functions. At the same time, it has a reasonable structure and is easy to operate. It is suitable for the teaching measurement and experiment of electronic technology courses in colleges and universities.

Description

Environmental temperature and humidity wireless monitoring and measuring instrument

technical field

The utility model relates to a wireless monitoring and measuring instrument for ambient temperature and humidity, which belongs to the field of electronic technology, physical measurement and experiment of colleges and universities.

Background technique

Temperature is one of the common and important physical parameters in production process and scientific experiments. In the actual production process, temperature measurement and subsequent control are closely linked to major technical and economic indicators such as production safety, production efficiency, product quality, and energy conservation. Humidity refers to the water vapor content in the gas, and hygrometers are often used in production to measure or control the humidity of air or industrial process gases.

Traditional temperature and humidity measurements mostly use manual measurement, which is more cumbersome and less efficient than automatic measurement. At the same time, the fixed temperature and humidity recorder can only be placed in a specific area, and in some cases, it is limited by the tested sample, working conditions and test area, so it is necessary to apply a portable temperature and humidity recorder that can record multiple test areas. measurement method. In order to ensure correct measurement data and consider the convenience of operation, it is necessary to develop an instrument that can wirelessly monitor and measure the temperature and humidity of the environment.

Utility model content

Aiming at the shortcomings of the existing measuring instruments, the utility model adopts the wireless single-chip microcomputer CC1110 to form the wireless transmitting and wireless receiving circuit, and combines the digital temperature and humidity sensor SHT11 as the sensing element to connect to the wireless transmitting end, and place it in the target environment to be measured It can receive the temperature and humidity of the working area within 200m. At the same time, the signal can also be connected to the computer through the RS-232 serial port communication, and the signal can be analyzed, calculated and processed.

The utility model is composed of a main unit of an environmental temperature and humidity wireless monitoring and measuring instrument and a wireless monitoring module. The main unit of the measuring instrument is equipped with a three-digit display temperature gauge, a three-digit display hygrometer, a power switch, a signal output port, an adjustment knob and a function selection switch. , The host of the measuring instrument has a wireless receiving circuit; the wireless monitoring module is provided with a measurement switch button and a rotatable transmitting antenna, and the wireless monitoring module has a temperature and humidity sensor and a wireless transmitting circuit.

The utility model consists of a wireless single-chip microcomputer chip CC1110 and a temperature and humidity sensor SHT11 to form a data collection terminal and a transmitting and receiving module. The main chip of the wireless receiving circuit in the host of the measuring instrument adopts the single-chip microcomputer CC1110. The temperature and humidity sensor in the wireless monitoring module adopts SHT11, and the wireless transmitting circuit also adopts the main chip CC1110.

The core device of the wireless communication circuit of the utility model is the CC1110 chip, which is a low-power wireless single-chip microcomputer produced by TI Company, and the chip includes a standard 8051MCU and a wireless transceiver chip. The 8051MCU comes with 32KB Flash and 4KB RAM, and also includes timers, watchdog timers, sleep mode timers for 32kHz crystal oscillators, power-on reset circuits, point drop detection circuits, and 21 I/O ports. The wireless signal of this system can work in the 315/433/868/915MHz frequency band. The RF radio frequency transceiver of CC1110 integrates a configurable modem, supports different modulation formats, and its data transmission rate can reach 500kb/s.

数字传感技术，具有极高的可靠性和卓越的长期稳定性，含有已校准的数字信号输出的温湿度复合传感器。其内部包括一个电容式聚合体测湿元件和一个能隙式测温元件，并与一个14位的A/D转换器以及串行接口电路集成在同一芯片上，它可与单片机直接相连，此外，该传感器还具有响应速度快、抗干扰能力强、性价比高等优点。The core device of the temperature and humidity acquisition circuit of the utility model is the SHT11 chip, which is a single-chip sensor launched by Sensirion in Switzerland, based on the world-leading

Digital sensing technology, with extremely high reliability and excellent long-term stability, contains a temperature and humidity composite sensor with calibrated digital signal output. Its interior includes a capacitive polymer moisture measuring element and an energy gap temperature measuring element, and is integrated with a 14-bit A/D converter and serial interface circuit on the same chip, which can be directly connected to the microcontroller. In addition, The sensor also has the advantages of fast response speed, strong anti-interference ability, and high cost performance.

The utility model combines the adjustment knob and the function selection switch, and can set the alarm point for the temperature and humidity of the measuring point. When the temperature and humidity exceed the set range, an alarm will be given.

Description of drawings

Figure 1 is the main unit of the environmental temperature and humidity wireless monitoring and measuring instrument, in which 1 is a three-digit display hygrometer, 2 is a three-digit display temperature gauge, 3 is a power switch, 4 is a signal output port, 5 is an adjustment knob, 6 is a Function selection switch.

Fig. 2 is a wireless monitoring module, in which 7 is a measurement switch button, and 8 is a rotatable transmitting antenna.

Figure 3 is a wireless communication circuit.

Figure 4 is the temperature and humidity acquisition circuit.

Detailed ways

In conjunction with the accompanying drawings, the working and circuit conditions of the ambient temperature and humidity wireless monitoring and measuring instrument will be described in detail below.

The current of the main chip CC1110 of the measuring instrument is lower than 16.2mA or 16mA in the receiving and transmitting modes respectively; in the sleep mode, the current is only 0.5uA, and the external interrupt or RTC can wake up the system; in the standby mode, the current is lower than 0.3uA, The external interrupt can wake up the system; the hardware supports CSMA/CA function; it has a wide voltage range: 2.0V ~ 3.6V; it also has DMA function and battery detection function.

In the wireless communication circuit, the high-speed clock source circuit of CC1110 is composed of 26MHz crystal oscillators X1, C20 and C21. The wireless receiving end of the system is powered by the mains power supply, so the power consumption can be ignored, so the high-speed clock source can be used. The wireless monitoring module working in the test area is powered by a battery and takes on the task of collecting temperature and humidity data. Considering the consumption of the battery, a low-speed clock source with low power consumption is used. The low-speed clock source circuit is composed of 32.768kHz crystal oscillator X2, C31 and C32.

The circuit composed of capacitors C12-C17 and inductors L10-L13 completes the conversion of the signal into a single-ended RF signal, and cooperates with the 50Ω antenna. Resistor R22 is used to set the bias current.

In the temperature and humidity acquisition circuit, the power supply voltage of the chip is 3.3V, and a 100nF capacitor C42 is installed between the power supply pin and the ground to play the role of decoupling and filtering. The serial interface is a two-wire structure. The serial clock input SCK is connected to P1.5 of CC1110 for communication synchronization between CC1110 and SHT11; the serial data DATA is a three-state gate structure, which is connected to P1.5 of CC1110. 4 connected for data reading. DATA changes state on the falling edge of SCK clock and is only valid on the rising edge of SCK. During data transmission, when the SCK clock is at a high level, DATA needs to remain stable. In order to avoid signal conflicts, a 10kΩ pull-up resistor R47 is installed to make P1.4 output a low level.

The measuring instrument can realize the real-time monitoring of the temperature and humidity of the test environment, multi-point wireless measurement and other functions. At the same time, it has a reasonable structure and is easy to operate. It is suitable for the teaching measurement and experiment of electronic technology courses in colleges and universities.

Claims (3)

1. ambient temperature and humidity wireless monitor measuring instrument, it is characterized in that: by ambient temperature and humidity wireless monitor measuring instrument main frame and wireless monitor module, formed, on the measuring instrument main frame, be provided with the aobvious humidometer (1) of three figure places, three figure place temperature display kilsyth basalts (2), power switch (3), signal output port (4), adjusting knob (5) and functional select switch (6), in the measuring instrument main frame, have wireless receiving circuit; On the wireless monitor module, be provided with measuring switch button (7) and rotatable emitting antenna (8), in the wireless monitor module, have Temperature Humidity Sensor and radio transmitter.

2. ambient temperature and humidity wireless monitor measuring instrument according to claim 1, is characterized in that: the wireless receiving circuit master chip employing single-chip microcomputer CC1110 in its main frame.

3. ambient temperature and humidity wireless monitor measuring instrument according to claim 1, is characterized in that: the Temperature Humidity Sensor employing SHT11 in its wireless monitor module, radio transmitter master chip employing CC1110.

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