Pressure Sensor Arduino nano Oem Sct-1 Problem

Projects General Guidance
1

hello, I connected the arduino nano directly to the sensor, but I can't get the correct value. You can find the schematic and codes below. I used Hx711 as amplifier for the sensor connection. I will use it for pressure. I see the value from the serial monitor section. Can you help me ?

SDDD
SDDD699×318 44.2 KB

Sensor datasheet = " OEM pressure sensor - SCT-1 - WIKA? "

#include "HX711.h" 

#define calibration_factor -7050.0 

#define LOADCELL_DOUT_PIN  2
#define LOADCELL_SCK_PIN  3

HX711 scale;

void setup() {
  Serial.begin(9600);
  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
  scale.set_scale(calibration_factor); 
  scale.tare();  

}

void loop() {
  Serial.print(scale.get_units(), 1); 
  Serial.print(" bar"); 
  Serial.println();
  delay(800);
}
2

VoAWZG
VoAWZG1200×1600 205 KB

3

What help do You need?
Searching this forum for " Arduino + HX711" will give lots of examples.

4

it does not read the data from the sensor, the result is wrong coding, I need help

5

No I think you have the wrong hardware connections.

That is where you are going wrong.
What is the sensor?

6

The subject has content.. Model "OEM SCT-1 pressure sensor "
OEM pressure sensor - SCT-1 - WIKA?

7

The sensor works at minivolt value. I used hx711 to increase the voltage, but the value appears to be 0 and 1, the pressure I applied is 3 bar. Measuring with a multimeter, there is no hardware problem. What can I do for the right value

8

:(( won't you be helping?

9

You have defined pins as d2/3 and have it connected to A4,A5 - that might mean something ?

I would run an example provided with the library, check mV output from the sensor .

10

Please measure the voltage on E+ of the HX711 module,
with the black probe held on the USB shield of the Nano.
If it's not 4.25volt then you could have a HX711 module with a production fault.
Leo..

11

There is no problem with the HX711, I installed a new one. It looks like a4 or a5 in the photo. But I connected it to d2 , d3 pin. I measured the mv values ​​with a multimeter, there is no problem. The value I get is 119.0, but when I apply pressure to the sensor, the value does not change and remains the same.

12

The new one could have the same problem.
So did you measure E+ (and E-).
4.25volt between E+ and metal shield of the USB socket.
0volt between E- and metal shield.
A+ and A- should measure half of E+
And there should be less than 20mV between them.
Leo..

13

You have the yellow wire from the HX711 connected to pin A7, A7 is analog ONLY, no good for digital (serial) signals.

14

I applied what you said. Volts as you said. there is no mistake. The photo on the subject is connected to the old current version d2 and d3 pins. I think there is something wrong with the coding but I can't figure it out.

15

I think there is no one on the forum to apply this sensor to the arduino.

16

The sensor is just a bridge. Show us a picture of the connections again.
From the right angle, so we can clearly see where they are going.

Is red connected to E+, and brown connected to E-
yellow to A- and orange to A+
Leo..

17

Hi, I was having the same problem and this page helped me. I recommend you to read it to solve your doubts. https://www.instructables.com/How-to-use-a-Flex-Sensor-Arduino-Tutorial/ keys

18

You can find the schematic and codes below

#include "HX711.h" 


#define LOADCELL_DOUT_PIN  2
#define LOADCELL_SCK_PIN  3

HX711 scale;

void setup() {
  Serial.begin(9600);
  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
  scale.set_scale(); 
  scale.tare();  


}

void loop() {
  Serial.print(scale.get_units(), 1); 
  Serial.print(" bar"); 
  Serial.println();
  delay(800);
}

The wiring diagram is as follows

Ekran Alıntısı
Ekran Alıntısı1021×396 302 KB

I don't understand where is wrong. I checked and changed all of them. No problems or malfunctions in any of them. The values ​​I got are as follows

Z23tDhdJ_8C61F959-9ED3-480E-B42E-4BB67FF88B91
Z23tDhdJ_8C61F959-9ED3-480E-B42E-4BB67FF88B911920×2560 1.17 MB

please help me :((

19

I see you changed the colours of the wires to the sensor.
Check wiring between HX711 and sensor again.
The connections don't seem to match sensor pinout in the datasheet.
Sensor datasheet, top to bottom in your picture: E+, A-, E-, A+

Clock and data pins in your last Fritzy also seem to be swapped.
Leo..

20

I tried everything but it doesn't work. Can anyone make the schematic and code from scratch?