Units Of Measurement conversion & chart

[Sim]

Hello, I’m using “Units Of Measurement” to convert values as this:

things/house.things

Type number       : pressure          "Pressure"           [ ga="<15/0/41" ]

items/house.items

Number:Pressure pressure  "Pressure [%.1f Pa]"  <pressure>   { channel="knx:device:bridge:meteo:pressure" }

sitemaps/house.sitemap

Text item=pressure label="Pressure [%.1f hPa]" {
  Frame {
    Switch item=Day_Period label="(PA)" mappings=[0="4h", 1="1D", 2="1W", 3="1M", 4="1Y"]
    Chart item=pressure period=4h refresh=10000 visibility=[Day_Period==0]
    Chart item=pressure period=D refresh=10000 visibility=[Day_Period==1]
    Chart item=pressure period=W refresh=10000 visibility=[Day_Period==2]
    Chart item=pressure period=M refresh=10000 visibility=[Day_Period==3]
    Chart item=pressure period=Y refresh=10000 visibility=[Day_Period==4]
  }
}

The value in label is correct, but the chart keep showing the unconverted values.
In KNX Binding there isn’t the option readTransform as Modbus…
Any idea?

Regards

[rossko57]

Charts are produced from persisted data.
OH2 persistence services do not yet really understand UoM, and only record a numerical value. The units are simply ignored by persistence.

Profiles are handy for transforms of binding data at the channel level … but currently only transform to a String Item, that’s no use to you either.

I think in the end, if you must chart different data from the raw data, you would need to use a proxy Item and a rule to do the numeric scaling and persist/chart your proxy.

[Sim]

Thank you for reply,

the simple solution would be “readTransform as Modbus…” but it’s not present in KNX binding

Regards