mirror of
https://github.com/weewx/weewx.git
synced 2026-04-26 12:37:10 -04:00
40 lines
1.4 KiB
Markdown
40 lines
1.4 KiB
Markdown
# [StdCalibrate]
|
|
|
|
The `StdCalibrate` service offers an opportunity to correct for any
|
|
calibration errors in your instruments. It is very general and flexible.
|
|
|
|
Because this service is normally run after `StdConvert`, the units to be used
|
|
should be the same as the target unit system chosen in
|
|
[`StdConvert`](../stdconvert). It is also important that this service be run
|
|
before the archiving service `StdArchive`, so that it is the corrected data
|
|
that are stored.
|
|
|
|
In a default configuration, calibrations are applied to observations from the
|
|
hardware. They are not applied to derived calculations since the
|
|
`StdWXCalculate` service runs after `StdCalibrate`.
|
|
|
|
## [[Corrections]]
|
|
|
|
In this section you list all correction expressions. For example, say that you
|
|
know your outside thermometer reads high by 0.2°F. You could add the
|
|
expression:
|
|
|
|
outTemp = outTemp - 0.2
|
|
|
|
Perhaps you need a linear correction around a reference temperature of 68°F:
|
|
|
|
outTemp = outTemp + (outTemp-68) * 0.02
|
|
|
|
It is even possible to do corrections involving more than one variable.
|
|
Suppose you have a temperature sensitive barometer:
|
|
|
|
barometer = barometer + (outTemp-32) * 0.0091
|
|
|
|
All correction expressions are run in the order given.
|
|
|
|
Both LOOP data and archive data will be corrected.
|
|
|
|
If you are using a Davis Vantage instrument and all you require is a simple
|
|
correction offset, this can also be done in the hardware. See your manual
|
|
for instructions.
|