Smartmeter Thing Protokol oms

Hello, I’m quite new to openhab and started with oh v3.1.0
i want to maximize my PV energy consumption and therefore it is necessary to know the actual power in and out values.
my SieḿensTD3511 smartmeter from my supplier Netz OÖ has enabled this possibility, and I was able to read the values using the Volkszähler Raspi App. I installed an IR read/write head onto the smartmeter and connected the device the usb port of the rasperry pi2 executing the volkszaehler app.
it was necessary to adopt the (Vzlogger.conf) file for using oms as transmition protokol as below

{
“retry”: 0,
“daemon”: true,
“verbosity”: 0,
“log”: “/var/log/vzlogger.log”,
“local”: {
“enabled”: false,
“port”: 8080,
“index”: true,
“timeout”: 3,
“buffer”: -1
},
“meters”: [
{
“enabled”: true,
“allowskip”: false,
“interval”: -1,
“aggtime”: -1,
“aggfixedinterval”: false,
“channels”: [
{
// Bezug Watt
“uuid”: “cbda11a0-fd28-11eb-af15-xxxx”,
“identifier”: “1.7.0”,
“api”: “volkszaehler”,
“middleware”: “http://localhost/middleware.php”,
“aggmode”: “none”,
“duplicates”: 0
},
{
// Einspeisung Watt
“uuid”: “288172b0-fd29-11eb-8e33-xxxx”,
“identifier”: “2.7.0”,
“api”: “volkszaehler”,
“middleware”: “http://localhost/middleware.php”,
“aggmode”: “none”,
“duplicates”: 0
}
],
“protocol”: “oms”,
“device”: “/dev/ttyUSB0”,
“baudrate”: 9600,
“key”: “xxxmykeyxxx”,
“mbus_debug”: false
}
]
}

to read the values…

Now I want to read the 2 values
Power In [Watt]
Power Out [Watt]
with oh3 with the same USB device connected to my obenhab raspberry pi3

after that i will subtract “Power In” from “Power Out” to know the exact sum of power +/-
and trigger switching actions to different electrical devices using oh3.