I’m using the Wi and another scale and they disagree!
If you’ve purchased the Sette 270Wi – we know that you ‘understand’ having consistency in your dosing is a key element to your brewing approach/method.
We partnered with Acaia in the development of the Sette for this very reason. Acaia comes from a background of lab-grade precision balances. They know absolute accuracy and helped us establish a factory 3 point linear calibration procedure.
What am I seeing? An auxiliary scale shows a different reading for a given output, compared to what the 270Wi says. For example, my 270Wi claims the dose is 18.0g but when I transfer the coffee to my other scale it reports a slight different weight (e.g. 18.2g).
Why am I seeing this variation? Basically…the two scales don’t have the same calibration at this point in time. Neither can be assumed as correct without verification. To ensure absolute accuracy, ALL scales require recalibration of varying frequency depending on conditions and resolution. If you are using data from two scales; then BOTH scales should be calibrated and cross-verified.
What is absolute accuracy? Absolute accuracy is a term that describes the reading of a given piece of hardware (scale) relative to an established international standard (the kilogram). For more info on the standard behind kilogram check this Wiki out.
How important is absolute accuracy? That is up to you, as there are a lot of ‘it depends’ involved, and there are diminishing returns when evaluating the cost/benefit of absolute accuracy. As a single example, we pulled a factory built 270Wi out of the box at our Bellevue office and found the accuracy to be 99.9% relative to the international standard. Keep in mind that the Wi has a resolution of 0.1g, so in this case the 0.1% error found in our out-of-box example will be negligible due to the rounding built into our algorithms.
What can I do about it? Buy a 500g calibration weight directly from Acaia and calibrate! Increasing the frequency of recalibration better maintains absolute accuracy of the scale.
Single Point Calibration: