# Load Cell and HX711 in UNO board **URL:** \ **Category:** Sensors\ **Created:** [April 14, 2026, 4:32pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925 "2026-04-14T16:32:14Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![albaren1](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/albaren1/32/1267667_2.png) [@albaren1](https://forum.arduino.cc/u/albaren1)\ **Post date:** [April 14, 2026, 4:32pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/1 "2026-04-14T16:32:14Z")
I’m working on a small-scale project using an Arduino Uno, an HX711 amplifier, and a 4-wire load cell. The setup works in the sense that I can read values from the HX711 and the weight changes when I apply force, but the readings are extremely unstable. Even when a constant weight is applied, the value keeps fluctuating and slowly drifting over time instead of stabilizing. For example, the measurement might start around a certain value and then gradually decrease or wander even though nothing is changing mechanically. Things I’ve already tried: - Averaging multiple samples using `scale.get_units(10)` - Re-taring the scale - Letting the HX711 warm up - Checking wiring multiple times - Powering the system through USB and through a separate supply - Ensuring the load cell is mounted properly and not touching other surfaces Despite all of that, the readings still fluctuate significantly. It makes the system very difficult to use for any measurement that needs even moderate stability. At this point I’m wondering if this behavior is just typical of cheap HX711 + load cell setups, or if I might have a defective load cell or amplifier module. Has anyone experienced similar instability with this setup? Are there known tricks to improve stability, or should I consider using a different ADC or higher quality load cell? Here is a sample of the output data: ���f��~怘����f�����`�fxx�������怘����f�����`�fxx�������怘�f�f���xfx□�~ff�~�`������怘�HX711 scale test HX711 not ready... HX711 not ready... Remove weight... Scale ready. Weight: -0.78 Weight: -8.28 Weight: -14.67 Weight: -19.47 Weight: -24.10 Weight: -28.21 Weight: -31.83 Weight: -35.17 Weight: -38.16 Weight: -41.01 Weight: -43.58 Weight: -46.16 Weight: -48.01 Weight: -50.11 Weight: -51.72 Weight: -53.03 Weight: -54.34 Weight: -55.44 Weight: -56.36 Weight: -57.51 Conections: ![image](https://europe1.discourse-cdn.com/arduino/original/4X/5/4/d/54d0346958f3c0e75f6dd8e85a1b6a97227d6bbe.png) ```arduino #include "HX711.h" #define HX711_DT 8 #define HX711_SCK 9 HX711 scale; float calibration_factor = 420.0; void setup() { Serial.begin(57600); delay(2000); Serial.println("HX711 scale test"); scale.begin(HX711_DT, HX711_SCK); while (!scale.is_ready()) { Serial.println("HX711 not ready..."); delay(500); } Serial.println("Remove weight..."); delay(3000); scale.set_scale(calibration_factor); scale.tare(); Serial.println("Scale ready."); } void loop() { float weight = scale.get_units(10); Serial.print("Weight: "); Serial.println(weight); delay(500); } ``` ![20260414_132501](https://europe1.discourse-cdn.com/arduino/original/4X/f/1/6/f166a6fc33a4a73e0936ba718ee2f8628eebdc6d.jpeg) ![20260414_132423](https://europe1.discourse-cdn.com/arduino/original/4X/d/1/1/d1173b1f8f0a929f412d7553f44b9a7a7fe3faba.jpeg) ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 14, 2026, 4:43pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/2 "2026-04-14T16:43:20Z")
> [@albaren1](#): > > Even when a constant weight is applied, the value keeps fluctuating and slowly drifting over time I had the same thing happen, I fixed it with the multiple readings, sort by value, take median API in the library, sorry don't recall the name. Your Serial output does NOT show fluctuating and drift, it is constrantly increasing. 1. Did you calibrate? 2. Post ALL your code in code tags. ---
**Author:** ![gilshultz](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gilshultz](https://forum.arduino.cc/u/gilshultz)\ **Post date:** [April 14, 2026, 5:05pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/3 "2026-04-14T17:05:17Z")
Post a picture of your wiring, that sounds a lot like noise. ---
**Author:** ![albaren1](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/albaren1/32/1267667_2.png) [@albaren1](https://forum.arduino.cc/u/albaren1)\ **Post date:** [April 14, 2026, 5:29pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/4 "2026-04-14T17:29:31Z")
Hello, I just added the code. Yes, I tried to calibrate, but since the values are always decreasing. It makes it difficult to know when it is the right value. ---
**Author:** ![albaren1](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/albaren1/32/1267667_2.png) [@albaren1](https://forum.arduino.cc/u/albaren1)\ **Post date:** [April 14, 2026, 5:30pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/5 "2026-04-14T17:30:15Z")
Just added a couple of pictures to the post. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 14, 2026, 5:43pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/6 "2026-04-14T17:43:17Z")
Please read the pinned post 'How to get the most from the Forum' In the future do NOT edit or add to an existing post, just add on. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 14, 2026, 5:46pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/7 "2026-04-14T17:46:12Z")
Did you run the example calibrate sketch? ---
**Author:** ![kmin](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/kmin/32/1147370_2.png) [@kmin](https://forum.arduino.cc/u/kmin)\ **Post date:** [April 14, 2026, 5:46pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/8 "2026-04-14T17:46:29Z")
> [@albaren1](#): > > the readings still fluctuate significantly hx711can output value between 0 and 8M for one direction, for sure they fluctuate. Take some approx. reading with no load and another with ~ half of the rated load of your cell. What digits you get? ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 14, 2026, 5:56pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/9 "2026-04-14T17:56:14Z")
Start with the example Kitchen scale. NOTE: all and every API call must be done in the exact order. The only changes to make to the example is the display part, the rest is correct as is. I used median\_avg and 15 samples. That gives a fairly clean result. ---
**Author:** ![jim-p](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/jim-p/32/922840_2.png) [@jim-p](https://forum.arduino.cc/u/jim-p)\ **Post date:** [April 14, 2026, 6:32pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/10 "2026-04-14T18:32:03Z")
Hi @albaren1 See this topic: > [@Load cell amplifier HX711 - wrong ground?](https://forum.arduino.cc/t/load-cell-amplifier-hx711-wrong-ground/1046075): > > Hi I have this type hx711 card I have read that ground is not properly connected to pin 5 on chip. Se yellow line for possible modification Can anybody confirm this? And is there a way to measure this with a multimeter? [image] M Check if missing ground. ---
**Author:** ![gilshultz](https://avatars.discourse-cdn.com/v4/letter/g/67e7ee/32.png) [@gilshultz](https://forum.arduino.cc/u/gilshultz)\ **Post date:** [April 15, 2026, 3:17am UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/11 "2026-04-15T03:17:28Z")
Your soldering needs a bit of practice. It looks like the iron was held a long time burning the wire and not hot enough to properly melt the solder. It appears you are using lead free, try a 60/40 from a known supplier such as Kester. You might try buying some DuPont type cables and cutting to length, that will keep the module pins clean. They cost less then a pack of cigarettes. The wire in some is very thin so be careful. Do not give up on the soldering practice. ![image](https://europe1.discourse-cdn.com/arduino/original/4X/b/1/2/b12c1fa261db2d26d4f48631b0f8501957780a58.jpeg) ---
**Author:** ![Wawa](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/wawa/32/1211303_2.png) [@Wawa](https://forum.arduino.cc/u/Wawa)\ **Post date:** [April 16, 2026, 8:33pm UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/12 "2026-04-16T20:33:48Z")
> [@gilshultz](#): > > They cost less then a pack of cigarettes. I hve seen you use this analogy before. Remember that this is a global site. Cigarette price differs a lot around the world. Here (NZ) a packet of 20 is US30.00 You can buy a shipload of dupond wires for that. Leo.. ---
**Author:** ![GolamMostafa](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/golammostafa/32/239011_2.png) [@GolamMostafa](https://forum.arduino.cc/u/GolamMostafa)\ **Post date:** [April 17, 2026, 2:00am UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/13 "2026-04-17T02:00:11Z")
> [@Wawa](#): > > You can buy a shipload of dupond wires for that. Here in BD, we can by at US$30.00 -- 23 x 20-pin x 30-cm male-to-male jumpers. ![image](https://europe1.discourse-cdn.com/arduino/original/4X/7/8/3/7834745b63564340f02f05079e352d074c62ca44.jpeg) ---
**Author:** ![xfpd](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/xfpd/32/1120236_2.png) [@xfpd](https://forum.arduino.cc/u/xfpd)\ **Post date:** [April 17, 2026, 4:08am UTC](https://forum.arduino.cc/t/load-cell-and-hx711-in-uno-board/1439925/14 "2026-04-17T04:08:54Z")
Data looks like a discharging capacitor. ![image](https://europe1.discourse-cdn.com/arduino/original/4X/8/c/5/8c5f2687af61925b51cd76203c5c125b7f413ee5.png)