Digital temperature sensor

Digital temperature and humidity sensor: It is a sensor that can directly read the physical quantity of temperature and humidity through the temperature and humidity sensitive elements and corresponding circuits, which is convenient for computers, plc, intelligent instruments and other data acquisition equipment.

Working principle

When the power supply is started, the digital temperature sensor is in the state of energy shutdown. After power supply, the user can make it in the continuous conversion temperature mode or single conversion mode by changing the register resolution. In the continuous conversion mode, the digital temperature sensor continuously converts the temperature and stores the results in the temperature register, reading the contents of the temperature register does not affect its temperature conversion; in the single conversion mode, the digital temperature sensor performs a temperature conversion, the results are stored in the temperature register, and then returns to the closed mode. This conversion mode is suitable for temperature sensitive applications. 。 In the application, users can set up resolution registers to achieve different temperature resolutions. The resolution of the registers can be 8 bits, 9 bits, 10 bits, 11 bits or 12 bits. The corresponding temperature resolutions are 1.0, 0.5, 0.25, 0.125 or 0.0625 degrees, respectively. The default resolution of the temperature conversion results is 9 bits. DS1722 has two communication interfaces: Motorola serial interface and standard three-wire interface. Users can select communication standard through SERMODE pin.

Typical Application of Digital Temperature and Humidity Sensor

Nowadays, with the increasing degree of informatization, the computer room, which is responsible for information processing and exchange, is the whole information network engineering.

Data transmission center, data processing center and data exchange center. In order to ensure the normal operation of the equipment in the computer room and the staff have one.

Good working environment is indispensable for monitoring the temperature and humidity of the computer room. Reasonable and normal temperature and humidity environment is the equipment of the computer room.

An important guarantee for regular operation.

The requirements of computer room site are mainly based on the national standard GB2887-89 Technical Conditions for Computing Site.

"GB9361-88 Computing Site Safety Requirements" and "GB50174-93 Computer Room Design Code". Along with the calculation

With the development of computer technology and the wide use of computer system, the environment of computer room must satisfy the temperature and humidity of computer equipment.

Technical requirements.

The temperature and humidity in the computer room are the necessary conditions for the normal operation of computer equipment. We must install them in a reasonable position in the computer room.

Temperature and humidity sensors are installed to realize 24-hour real-time monitoring of temperature and humidity, and can be implemented on the monitoring host of the central control room.

Temperature and humidity measurements at various locations are displayed. Once the value exceeds the upper and lower limits of the preset temperature and humidity, it can be monitored on the host computer.

Alarm is given by changing the numerical color of the corresponding position. In order to monitor the temperature and humidity of the whole room in general, fresh air can be used.

Temperature and humidity transmitters are installed in the air inlet of the machine and the return air outlet of the main air conditioner respectively to detect temperature and humidity.

Temperature and humidity monitoring can be used not only in machine room monitoring, but also in biopharmaceuticals, sterile room, clean workshop and electricity.

Places and fields where temperature and humidity monitoring is needed in all walks of life, such as credit banks, libraries, archives, cultural relics, intelligent buildings, etc.

II. Characteristics of application schemes

High-performance temperature and humidity transmitter is adopted with high accuracy and stability.

Digital signal transmission, convenient wiring, signal transmission distance.

Open communication protocol, easy to expand the system.

Configuration software interface ensures system stability.

Software is rich in functions, practical, easy to maintain and upgrade.

3. System Hardware Configuration

1. Hardware requirements of PC:

Microsoft Windows 2000 (Chinese version) or Windows XP operating system (Chinese version).

IBM PC and its compatible computers, Pentium 500 MH CPU, 64 M memory.

(3) More than 10G hard disk, more than 200M free hard disk space.

(4) SVGA graphics card PCI or AGP graphics card, more than 16M display memory

2. On-site hardware configuration:

(1) RS485/232 conversion module

(2) JCJ100N Digital Temperature and Humidity Transmitter

(3) AC/DC power converter 220VAC/12VDC 2A or on-site 12DC/2A DC power supply

IV. System Structure

The system uses COM1 serial port to connect RS485/232 converter to collect data.

(2) System communication mode: RS485/232, two-wire data+, data-, baud rate: 9600 BPS

(3) Working voltage: 220 VAC + 10%, or 12 VDC + 10% 2A

V. System Configuration Description

1. Digital temperature and humidity transmitter

Digital temperature and humidity sensor sampling card has 10-bit dual-channel successive approximation A/D converter, standard RS-232 or

485 communication interface. This product adopts the filtering method of combining recursive average digital software filtering with hardware circuit filtering, which makes the outside world pair with each other.

Sampling interference is minimized as far as possible, with high accuracy, strong stability, good consistency and fast response.

A multi-point temperature and humidity measurement system (up to 256 digital temperature and humidity sensors) can be composed of a standard 485 serial interface and a computer.

Description of main parameters:

Operating Voltage: 12V-24VDC

Temperature measurement range: 0-50-20-60-40-80, other notes.

☆ 准 确 度：优于±0.5℃(0～50℃)

Moisture measurement range: 0-100% RH

☆ 准 确 度：±3%RH（20%～90%RH，23℃）；±2%RH（20%～90%RH，23℃）

Signal Output: Standard RS485 Interface

Address settings: Built-in dial switch, 32 address settings (hexadecimal 00-1F)

2. Data Software Description

Installation and ready-to-use: The software is easy to install. Click "Setup.exe" to run and complete the installation without any other settings.

Use, real ready-to-use.

Multiple interfaces: real-time digital display, real-time curve, historical curve, data report, configuration report and other data display