Divide KNX item value by 1000

Setup, Configuration and Use Beginners
1

Hi,

can you help me to divide an item by 1000? I’m struggling with the syntax here I think:

Thing/Channel:

Type number: PWR_Hzg_ZaehlerGes “PWR Heizung Gesamtverbrauch” [ga=“13.001:<3/7/100”]

Item:

Number PWR_Hzg_ZaehlerGes “Stromzähler Wärmepmpe [JS(divideBy1000.js):%s kWh]” { channel=“knx:device:bridge:generic:PWR_Hzg_ZaehlerGes”}

divideBy1000.js:

(function(i) {
return parseFloat(i) / 1000;
})(input)

the division works, but how can I show the number with two decimals? Also on PaperUi shows the item value as “JS(divideBy1000.js):130kWh”

Thanks,
Klayman

2

Just add toFixed(num_of_decimals)

3

Thanks. It worked, although it seems that PaperUI can’t show the transformed value under the default “Control” section.

4

That is perfectly right if you added the transformation to the sitemap. The control page is more or less to show that the item you have setup is working.

5

why this is not showing anymore the specified unit “kWh”? the division works, but in the sidemap i am missing the units! If puting there again “value [%s kWh]” … i get the value without the division…

6

You should use [%.3f kWh] because the value is a float the 3f means three digits behind the decimal point, so you could also use [%.1f kWh] for one digit.
If you want a number without decimals [%d kWh] do not use [%s kWh] that is for text.

7

its not working! the unit will be ignored if you use the javascript to change decimal point…

umber inverter1ActivePower           "Aktuelle PV-Produktion [JS(divide1000.js):%.3f kWh]"           <solarplant>	    (gSMA)             {channel="modbus:data:inverter1:Active_Power:active_power:number"}

output is without “kWh”, only the correct value now in kW not more in W

8

Just change your JS to something like this. Add the unit after all your calculations

;(function (i) {
    var recVal = parseFloat(input)/1000
    return recVal + ' Watt'
})(input)
9

Thanks great! its working!