Drifting Load cell in a stable environment

[Modesty]

Hi helping members.

I think I have got a lot of info and learning regarding load cells, thanks a lot!

I feel that @DaveEvans summarize it for me. I think I give up the on point load cell and go back to my first system, 4 load cells, mounted on the bee hives "bottom" stand, then on the main hive stand I add some hard plastic (snow scrape type) where the load cells rest on the hive bench.

Reason I did not continue using the 4 load cells was that I could not find reasonable priced cells that delivers a datasheet, I only found "alibaba" type for 2$ + a green HX711. And if you read this tread you see that I struggled to make a stable system.

Have you a tip where I can buy a reasonable good load cells that have load 24/7-365 for a reasonable price, I don't need HX711, that is integrated on my PCB?

M

[DaveEvans]

I don't know of a good source for that sort of load cell. See below for a list of some reputable manufacturers. They may have what you're looking for (but I'm skeptical).

However, if I were you, I'd consider trying the one cell idea mentioned in #142 and shown in the sketch below, provided that I:

1. liked my existing load cell
2. didn't mind that I'd be using less of the available range of the cell (since it would be only carrying approximately half of the hive weight, not the full weight)
3. didn't mind that the changing hive c.g. (as the bees create honey) will distort the measurements

Issue 2 could be resolved by buying a load cell with a smaller capacity.

A list of some load cell manufacturers:

• Omega
• Futek
• HBM
• Honeywell
• Vishay/BLH

[Modesty]

Hi

an update for you / my helpers last 2 years

Scale vs. temp, 48 h
Pretty interesting

Scale is stable within 9 grams, and it is due to temp changes

I will not make a calibration code for this as long as it is this accurate, and I will only use 1 desimal
so load is 25.3 kg, and that is what is on it (my calibration laod)

[Modesty]

Now I'm ready to give the Bee montor system to my wife. > 2 years work as hobby.

This is from a real time test. Without a bee hive on top, but with all stuff running, and display on Home Assistant.

Example

[madlan]

Any update on your project? Is it working well since deploying?

[Modesty]

Hi @madlan

PCB v2 is working , some problem with solar charging.

I have prepared a PCB v3, not ordered jet, there I use superCapasitor as power, lipo backup..

I try to keep first post updated, so please read that also.

PCB3:

[Modesty]

Hi

Finally, PCB v3 is ready for production. Cant wait to test using super capacitor as main power source.

This is my sensor connecting PCB, this way I can remove main PCB for service.