Simulation design of boiler water level, temperature and pressure detection system based on 51 microcontroller

Simulation diagram proteus7.8 and above

Program compiler: keil 4/keil 5

Programming language: C language

Design number: S0056

1. Main functions:

Based on 51 microcontroller AT89C51/52 (common to 51 core microcontrollers such as AT89S51/52, AT89C51/52, STC89C51/52)

1. The system displays the water level detection value, boiler furnace temperature value, and boiler internal pressure value through LCD1602 in real time.

2. The upper and lower limits of the boiler water level, the upper and lower limits of the furnace temperature, and the upper and lower pressure limits can be set. The first line displays the upper limit value, and the second line displays the lower limit value.

3. If the water level, temperature and pressure exceed the limit, the buzzer will alarm and the alarm type will be indicated by LED.

4. The default lower limit of water level is 10cm, the upper limit is 40cm, the lower limit of pressure is 30kPa, the upper limit of pressure is 50kPa, the lower limit of temperature is 5℃, and the upper limit of temperature is 105℃.

5. The temperature sensor uses DS18B20; the water level sensor uses potentiometer simulation; the pressure sensor uses MPX4115.

The following is a display diagram of this design information:

2. Simulation results

Start simulation

Open the simulation project, double-click the microcontroller in proteus, select the hex file path, and then start simulation.

After starting the simulation, adjust the temperature to become larger. When the temperature of 106°C is greater than the upper temperature limit of 105°C, the buzzer will alarm and the upper temperature limit indicator will light up.

Adjust the temperature to become smaller. When the temperature is 4℃ lower than the lower temperature limit of 5℃, the buzzer will alarm and the lower temperature limit red light will light up.

During the simulation, adjust the value of the MPX4115 pressure sensor by pressing the buttons to change the displayed value. Adjust the pressure to become smaller. When the pressure is adjusted to 52kPa and is greater than the upper limit value, the buzzer will alarm and the red light of the upper limit air pressure alarm will light up.

Adjust the pressure to become smaller. When the pressure is adjusted to 26kPa and is lower than the lower limit value, the buzzer will alarm and the red light of the lower limit air pressure alarm will light up.

In the simulation, the resistance of the RV2 sliding rheostat is adjusted by pressing the buttons to simulate the change of the water level sensor with the height of the water level. The up and down arrows are used to change the resistance value. The down arrow decreases the value, and the up arrow increases the value.

Adjust the water level to become lower. When the water level is adjusted to 9CM and is lower than the lower limit value of 10CM, the buzzer will alarm and the red light of the lower limit of the water level will light up.

Adjust the water level to become higher. When the water level is adjusted to 41CM and is higher than the upper limit value of 40CM, the buzzer will alarm and the upper limit red light of the water level will light up.

After starting the simulation, you can enter the setting mode through the setting button of the matrix keyboard to adjust the default water level lower limit value, upper limit value, pressure lower limit value, pressure upper limit value, temperature lower limit value and temperature upper limit value. After entering the setting mode, the first line of LCD1602 displays the upper limit value, and the second line displays the lower limit value. After setting is completed, press OK to exit the setting.

The above simulation results are in line with the design requirements.

code

Use keil4 or keil5 to compile, the code has comments, and you can understand the meaning of the code in conjunction with the report.

Schematic diagram

The schematic diagram is drawn using AD and can be used for physical reference.

The difference between Proteus simulation and physical works:

1. Running environment: Proteus simulation runs on the computer, while the real thing runs on the hardware circuit board.

2. Debugging method: In Proteus simulation, you can easily perform single-step debugging and observe changes in variable values, while in real objects, you need to debug through a debugger or serial port output.

Circuit connection method: In Proteus simulation, the circuit connection can be modified through software settings, but in the real thing, it needs to be modified through the hardware circuit board and connecting wires.

3. Running speed: Proteus simulation usually runs faster than the real thing, because the simulation is based on computer operation, while the real thing needs to consider factors such as the physical limitations of the circuit board and the response time of the device.

4. Function realization: In Proteus simulation, different functions can be realized through software settings, but in real objects, they need to be realized according to the circuit design and device performance.