ELEGOO 5PCS HC-SR04 Ultrasonic Module Distance Sensor Kit

These have worked great for sensing water level. I have had it sitting at the top of a sealed tank with two holes just big enough for the sensors to fit. I DIYed an enclosure out of an old plastic case that some GRK screws came in. This is absolutely not the recommended way to use them, but have been receiving accurate measurements for the last ~3 weeks with a 15 second update interval running 24/7.

These are decent inexpensive ultrasound detectors. I use them on my little robots to avoid obstacles. And on on stationary devices to detect motion. And they are fairly accurate less than a centimeter for nearby objects. They’re good out to about 200 cm’s.

Complete project description follows but the keys for the Ultrasonic Distance Sensor: 1) it's been running in a plastic box, outside, for almost a month with no problem. The Arduino wakes us every 15 minutes and takes a measurement, transmits it, then goes back to sleep. 2) it is measuring the distance TO WATER! I even turned the swim jets in my pool on to test turbulence and it works fine.Green Pond Bridge Boat ClearanceAt ‘very low tide’ the clearance under Green Pond Bridge in Cape Cod is 6’6” or less and that is too low for the boat I use. The tide charts for Falmouth, MA are theoretical and can vary as much as 18” from what is actually happening at the bridge. This system monitors the clearance and transmits the information on the internet.All of these parts were purchased from Amazon.TransmitterAn (Arduino) Elegoo UNO R3 board is connected to an Elegoo HC-SR04 Ultrasonic Distance Sensor. The UNO and the sensor calculate the distance from a fixed dock to the sea level, then transmit that data using a MakerFocus NRF24L01 Wireless Transceiver to the Receiver described below. The Transmitter sits on the end of a dock where there is no power, so the UNO, Transceiver and Distance Sensor are powered by the energyShield 2. This battery has special capabilities – it wakes everything up every 15 minutes. The system takes a couple readings of the distance to the water then transmits that data, then the battery shuts it all off. The data transmitted includes information from the battery – time, date, and voltage.I have been testing this unit at home (in Dallas) and it has been operating outside, for about 20 days. Based on battery drain it looks like it will operate for about 4-5 months before it needs a recharge. When the temperature drops below zero the system still works fine but the voltage reported in the battery seems low.All of this is housed in a plastic box printed for the purpose with a FlashForge 3d Printer Creator Pro, using eSun White ABS+ filamentPicture below.ReceiverAn (Arduino) Elegoo MEGA 2560 R3 is connected to another NRF24 Transceiver to receive the data. The MEGA does the math to convert the distance from the dock to the water, to the bridge clearance. Then the information is displayed on an Elegoo UNO R3 Touch Screen (that also works fine on the Mega).Picture below. A small plastic frame for the Receiver was also printed on the 3d printerWeb ServerFinally, the information in the MEGA is transmitted over a serial bus to a Hiletgo ESP8266 NodeMCU ESP-12E Internet WIFI Development Board (Also operates using Arduino IDE programming). This board is connected to the MEGA via the XCSOURCE Logic Level Converter and powered by a UCEC MB102 Breadboard Power Supply Module. All mounted on an Elegoo Breadboard. The ESP8266 is programmed to be a web server. It connects to the internet through the modem/router provided by AT&T.Picture of my cell phone below.

Super fast delivery, excellent quality sensors. I’m working on a project and will definitely order from this seller again, anytime. Grateful for the help, thank you.

These are pretty useful devices. The distant measurements are pretty accurate. I placed a ruler out from the front of the sensor and measured at various distances from the Arduino serial port. Inside of 11cm, the distances were 1 cm off when using integer variables. At 12 cm and over, I got accurate measurements for all whole centimeter tests. If you want to do measurements of 11cm or less or need fractions of centimeters, you should use floating point variables.

Great selection for the project i am working on.

Great

A nice plus are the Dupont wires provided. However the 5 sensors have a total of 20 connections. Yes there are 20 wires provided but 10 are female-male and 10 are female-female. It would be nicer if there were 20 of each since you want female-male to connect to breadboards.FYI, if you use them with the one wire (bidirectional) configuration and add a 74HC4051 mux/demux you can drive 8 of these with only four pins on the Arduino.

These little modules work great and are sold in a group of 5 for a great price. All 5 come bundled in a single anit-static bag, and were well packaged. Also, did you see that last line where Elego mentions they include "a little gift"? I missed that, and it was a pleasant surprise. No spoilers, but that little gift was a great help in connecting up those sensors. The range is listed to 500 cm but I started to get large margin of errors past 400 cm. I also couldn't read closer than 4 cm (not 2 cm). To get a more accurate reading within the 4 cm to 400 cm range, I found taking a moving average of the last 3 readings to be good enough to do the trick. If you're not picky, one reading is sufficient.The PCB is well designed - it is the minimum size to hold the sonic sensors, rugged and firm. There are 4 pins; two for 5v and GND, 1 to TRIGGER it, and one to read the ECHO from. Usage is actually quite simple:1. Send a pulse to the TRIGGER pin to start the ranging;2. Measure the time in microseconds that it takes the ECHO pin to respond;3. Divide the time taken by a constant (manufacturer provided; it is 58.0 for CM) to get the distance.I'm not sure how much Amazon will allow me to write in a review, but I'm including the minimalist sketch (no comments) below to get you started (for Arduino, sorry, I'm not familiar with Pi). This will loop the ranging while reporting the distance in CM to the SERIAL MONITOR window in the Arduino IDE every second:--- Example Minimalist Sketch for HC-SR04 in Arduino --/* HC-SR04 Sonic Ranging Sensor5v to VCC7 to Trig8 to EchoGND to GND */void setup(){pinMode(7, OUTPUT);digitalWrite(7, LOW);Serial.begin(9600);}void loop(){unsigned long start;digitalWrite (7, HIGH);delayMicroseconds(10);digitalWrite (7, LOW);// Wait - for ECHO pulsewhile (digitalRead(8) == 0);start = micros();while (digitalRead(8) == 1);Serial.println ((micros() - start) / 58.0);delay(1000);}--- End ---

Awesome, good quality

Funziona perfettamente. Utilizzato per riempire una vasca fino a livello x.

Ottimi sensori poi arrivano pure con cavi maschio femmina e femmina femmina inclusi

Well presented, quality work and quick delivery.