# Parameter `ChangeRateThreshold`
Default Value: `2`

Range: `0` .. `9`.

Threshold parameter for change rate detection.<br>
This parameter is intended to compensate for small reading fluctuations that occur when the meter does not change its value for a long time (e.g. at night) or slightly turns backwards. This can eg. happen on watermeters.

It is only applied to the last digit of the read value (See example below).
If the read value is within PreValue +/- Threshold, no further calculation is carried out and the Value/Prevalue remains at the old value.

!!! Note
    If you edit the config file manually, you must prefix this parameter with `<NUMBER>` followed by a dot (eg. `main.ChangeRateThreshold`). The reason is that this parameter is specific for each `<NUMBER>` (`<NUMBER>` is the name of the number sequence defined in the ROI's).

## Example

- Smallest ROI provides value for `0.000'x` (Eg. a water meter with 4 pointers behind the decimal point)
- ChangeRateThreshold = 2
  
#### With `ExtendedResolution` **disabled**
PreValue: `123.456'7` -> Threshold = `+/-0.000'2`.<br>
All changes between `123.456'5` and `123.456'9` get ignored
	
#### With `ExtendedResolution` **enabled**
PreValue: `123.456'78` -> Threshold = `+/-0.000'02`.<br>
All changes between `123.456'76` and `123.456'80` get ignored.

![](img/ChangeRateThreshold.png)
