Water flow sensor, YF-S401, YF-S402, Flow meter, air from the pump

[grzeniux]

Hi, I have a problem with the flow meter
Generally the flow meter catches air, which makes me unable to take accurate measurements.
Correction, maybe not so much that the flow meter is catching air, because there is no signal on the logic state analyser during air. The signal is only there when water is actually flowing.
I am attaching a screenshot where I have set the pump to take a measured 20ml three times, and let's say this would agree with the measurements I used to take "dry", i.e. without a water pump just pouring into the sensor And then it agreed that:
ML = totalImpulses * 0.48 ;

 

 

 

 

I got rid of the pins that the water pump was giving by adding a 10nF capacitor between the pump supply

 

Below I attach the code I uploaded to the STM32L432KCU6 nucleo

And the stm32CUBEide settings

The components I am using:

* Pump: https://botland.store/pumps/7206-liquid-pump-12v-110l-h-7mm-5904422335595.html

* Sensor: https://botland.store/flow-sensors/4411-liquid-flow-sensor-yf-s402-6lmin-m11x125-thread-5904422373900.html

Video:

https://drive.google.com/file/d/1n6x9XY8-xxHOtbEWO173gqmJYZqNjTSB/view?usp=sharing

Does anyone know what I am doing wrong? How do I correctly count the liquid already flowed?

[grzeniux]

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define Pump GPIO_PIN_11
#define IN1 GPIO_PIN_3
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

 struct lcd_disp disp;

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim){
 	if(htim->Instance == TIM6)
 	{
 	//	sprintf((char *)disp.f_line, "Shoty");
 	//	sprintf((char *)disp.s_line, "Driny");
 		lcd_display(&disp);
 		
 	}
 }


/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */


uint16_t flowsensor = GPIO_PIN_4; // Zmień na odpowiedni pin

volatile int flow_frequency;
float vol, l_minute;
float xy = 0.0;
//unsigned char flowsensor = 2; // Sensor Input
unsigned long currentTime;
unsigned long cloopTime;
unsigned long totalImpulses = 0; // Nowa zmienna do przechowywania liczby impulsów
float imp = 0;
float total_ml;
float ML;

void flow () // Interrupt function to increment flow
{
 flow_frequency++;
 totalImpulses++;
}


struct lcd_disp disp;


/* USER CODE END 0 */

/**
 * @brief The application entry point.
 * @retval int
 */
int main(void)
{
 /* USER CODE BEGIN 1 */

 /* USER CODE END 1 */

 /* MCU Configuration--------------------------------------------------------*/

 /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
 HAL_Init();

 /* USER CODE BEGIN Init */

 /* USER CODE END Init */

 /* Configure the system clock */
 SystemClock_Config();

 /* USER CODE BEGIN SysInit */

 /* USER CODE END SysInit */

 /* Initialize all configured peripherals */
 MX_GPIO_Init();
 MX_USART2_UART_Init();
 MX_I2C1_Init();
 MX_TIM6_Init();
 /* USER CODE BEGIN 2 */
 	disp.addr = (0x27 << 1);
	disp.bl = true;
	lcd_init(&disp);

	// HAL_GPIO_WritePin(GPIOB, IN1, GPIO_PIN_RESET);
	 HAL_GPIO_WritePin(GPIOA, Pump, GPIO_PIN_RESET); // TRUN ON PUMP



 /* USER CODE END 2 */

 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {

		 currentTime = HAL_GetTick();
	 // Every second, calculate and print litres/hour
	 if (currentTime >= (cloopTime + 1000))
	 {
	 cloopTime = currentTime; // Updates cloopTime
	 if (flow_frequency != 0)
	 {
	 l_minute = (flow_frequency / 9.8); // (Pulse frequency x 60 min) / 9.8 Q = flowrate in L/hour

	 // Przeliczenie ilości impulsów na ilość mililitrów
	 // float ml_per_impulse = 0.95;
	 // total_ml = totalImpulses * ml_per_impulse;

	 // l_minute = l_minute / 60;
	 // l_minute = l_minute * 1000;
	 // vol = vol + (l_minute / 7.58);
	 vol = vol + l_minute;
	 xy = vol * 1000;
	 xy /= 200;

	 ML = totalImpulses * 0.48 ;


	 sprintf((char *)disp.f_line, "I: %lu, ml: %2.2f, ", totalImpulses, ML);
	 lcd_display(&disp);

	 // Dodanie informacji o ilości impulsów i ilości mililitrów
	 sprintf((char *)disp.s_line, "p: %2.2f, %2.2f ml", vol, total_ml);
	 lcd_display(&disp);

	 flow_frequency = 0; // Reset Counter
	 }
	 else
	 {
	 // Dodanie informacji o ilości impulsów i ilości mililitrów
	 // sprintf((char *)disp.f_line, "%.2f, I: %lu, %.2f ml, ", xy, totalImpulses, total_ml);
	 sprintf((char *)disp.f_line, "I: %lu, %2.2f ml, ",totalImpulses, ML);

	 sprintf((char *)disp.s_line, "V: %2.2f X", vol);
	 lcd_display(&disp);
	 }
	 }



 /* USER CODE END WHILE */

 /* USER CODE BEGIN 3 */
 }
 /* USER CODE END 3 */
}

/**
 * @brief System Clock Configuration
 * @retval None
 */
void SystemClock_Config(void)
{
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

 /** Configure the main internal regulator output voltage
 */
 if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure LSE Drive Capability
 */
 HAL_PWR_EnableBkUpAccess();
 __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);

 /** Initializes the RCC Oscillators according to the specified parameters
 * in the RCC_OscInitTypeDef structure.
 */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE|RCC_OSCILLATORTYPE_MSI;
 RCC_OscInitStruct.LSEState = RCC_LSE_ON;
 RCC_OscInitStruct.MSIState = RCC_MSI_ON;
 RCC_OscInitStruct.MSICalibrationValue = 0;
 RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_6;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_MSI;
 RCC_OscInitStruct.PLL.PLLM = 1;
 RCC_OscInitStruct.PLL.PLLN = 40;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV7;
 RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
 RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }

 /** Initializes the CPU, AHB and APB buses clocks
 */
 RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
 |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
 {
 Error_Handler();
 }

 /** Enable MSI Auto calibration
 */
 HAL_RCCEx_EnableMSIPLLMode();
}

/* USER CODE BEGIN 4 */


void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
 if (GPIO_Pin == flowsensor)
 {
 // HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_3);
 flow();
 }
}




/* USER CODE END 4 */

/**
 * @brief This function is executed in case of error occurrence.
 * @retval None
 */
void Error_Handler(void)
{
 /* USER CODE BEGIN Error_Handler_Debug */
 /* User can add his own implementation to report the HAL error return state */
 __disable_irq();
 while (1)
 {
 }
 /* USER CODE END Error_Handler_Debug */
}

#ifdef USE_FULL_ASSERT
/**
 * @brief Reports the name of the source file and the source line number
 * where the assert_param error has occurred.
 * @param file: pointer to the source file name
 * @param line: assert_param error line source number
 * @retval None
 */
void assert_failed(uint8_t *file, uint32_t line)
{
 /* USER CODE BEGIN 6 */
 /* User can add his own implementation to report the file name and line number,
 ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
 /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

[Techn]

These kinds of sensor just give you a count whether you blow air into it or water flows through it. so volume is number of count/second X area of the tube. It is assumed that the tube is full. If you need to measure very accurate, better to take the weight of the liquid using sensitive balance.

[LooOnSTM]

Hello, I'm also doing a project with stm32 and flow sensor, can you tell me something?