Hi,
I would like to build a scale for my beehive this winter.
But what are the difference between the Bosche H40A and H30A, when I select the 200kg model?
I can see that the H40A has a max “Max. Plattformgröße: 500 x 500 mm” and the H40A says “Max. Plattformgröße: 400 x 400 mm”
I will use it for a Langstroth beehive.
Thanks in advance.
We have used both load cells for bee scales, the Bosche H40 is with 150 x 50 mm and a hight of 40 mm a bit more bulky but also more stable then the Bosche H30 with 150 x 35 x 40.
The specified plattform size is funny because Bosche changed it, see:
Thanks for the feedback, Clemens.
The only difference is in the datasheet I could see is regarding:
Characteristic value of the relative minimum division value
d. WZ (Y = Emax / vmin)
% from Emax
H40A = 15.000
H30A = 7500
Which means that the H30A has a better resolution.
For my first scale I will select the H40A.
I would not count on that because it is in the “datasheet” the same for all types of rated load (“Nennlast”). But the possible H40 load cells are “only” available form 100 to 500 kg mens 1 to 5x. In camparison H30 load cells are produced for 15 kg max up to 300 kg, mens 1 to 20x:
I would expect that it is the same in case you compare a 100 kg H30 and a 100 kg H40.
But the H40 is a good choice for a single point load cell and more stable than the H30 with the “downside” of a bit more bulky.
I usually cut weight values after 2 kg decimals in the firmware anyways to avoid noisy time series. 10g precision is a good compromise for bee hive scales.
And I prefer more robust cells unless using a two-point scale setup. Imagine a high tower of supers (up to 5 for me) in honey season with a single-point suspension. It will get shaky quickly
That makes sense.
I am planning to use a ESP32 (ESP-NOW) for the communication between the scale and the gateway to wifi.
Any pointers to github projects for firmware, that can be used as a starting point?