Modbus not working on second solar system. No errors reported

I use Modbus for my SMA solar system for years. I have now a additional system from Kaco what also supports Modbus. I can read values with the utility modbus poll. I copied the sma things file made some adjustments and created a kaco.things file. In the GUI everything is online and there are no errors in the logfile. All values stay NULL. Who knows what to do as next step to troubleshot this or knows how to fix this?
Kaco.tings

Bridge modbus:tcp:blueplanet "Kaco 7.5 TL3 2MPP" @ "Zolder" [ host="192.168.100.116", port=502, id=3 ] {
     Bridge poller KACO_Poll_Totaal "KACO_Poller_Totaal" [ start=40085, length=14, refresh=2000, maxTries=2, type="holding" ] { 
        Thing data KAGO_Totaal "KACO_Input_Totaal" [ readStart="40085", readValueType="uint16"] //, readTransform="JS(divide1000.js)"] 
        Thing data KACO_Vandaag "KACO_Input_Vandaag" [ readStart="40095", readValueType="uint32"]  
    }
    Bridge poller KACO_Poll_TEMP "KACO_Poller_HeatSink" [ start=40104, length=4, refresh=2000, maxTries=2, type="holding" ] { 
       Thing data KAGO_Totaal "KACO_HeatSink_Temp" [ readStart="40104", readValueType="int16"] //, readTransform="JS(divide1000.js)"] 
    } 
}

sma.things (working fine)

Bridge modbus:tcp:tripower "SMA Sunny Tripower 5000TL-20" @ "Zolder" [ host="192.168.100.85", port=502, id=3 ]  { 

    Bridge poller SMA_Poll_Totaal "SMA_Poller_Totaal" [ start=30531, length=10, refresh=2000, maxTries=2, type="holding" ] { 
        Thing data SMA_Totaal "SMA_Input_Totaal" [ readStart="30531", readValueType="uint32", readTransform="JS(divide1000.js)"]  
        Thing data SMA_Vandaag "SMA_Input_Vandaag" [ readStart="30535", readValueType="uint32", readTransform="JS(divide1000.js)"] 
    } 
    Bridge poller SMA_Poll_Huidig "SMA_Poller_Huidig" [ start=30775, length=8, refresh=2000, maxTries=2, type="holding" ] {
        Thing data SMA_Huidig "SMA_Input_Huidig" [ readStart="30775", readValueType="int32", readTransform="JS(smalimit.js)"]   

    }
} 

items file Kaco

Number:Energy               KACOAbsoluutPerDag               "Vandaag [%.3f kWh]"             <solarplant>   (KACOOmvormer)      ["Measurement", "Power"]        {channel="modbus:data:blueplane:KACO_Poll_Totaal:KACO_Vandaag:number", widgetOrder = "2"}
Number:Energy               KACOTotaalOpgewekt               "Totaal [%.3f MWh]"              <solarplant>   (KACOOmvormer)      ["Measurement", "Power"]        {channel="modbus:data:blueplane:KACO_Poll_Totaal:KAGO_Totaal:number", widgetOrder = "6"}
Number:Temperature          KACOTemperatuur                  "Heat Sink temp"                 <solarplant>   (KACOOmvormer)      ["Measurement","Temperature"]         {channel="modbus:data:blueplane:KACO_Poll_Temp:KACO_HeatSink_Temp:number", widgetOrder = "7"}

Items file from SMA (working fine)

Number:Energy               SMAActueel                      "Actueel [%.0f W] "             <solarplant>    (Omvormer)      ["Measurement", "Power"]        {channel="modbus:data:tripower:SMA_Poll_Huidig:SMA_Huidig:number" ,widgetOrder = "1" }
Number:Energy               SMAAbsoluutPerDag               "Vandaag [%.3f kWh]"            <solarplant>    (Omvormer)      ["Measurement", "Power"]        {channel="modbus:data:tripower:SMA_Poll_Totaal:SMA_Vandaag:number", widgetOrder = "2"}
Number:Energy               SMATotaalOpgewekt               "Totaal [%.3f MWh]"             <solarplant>    (Omvormer)      ["Measurement", "Power"]        {channel="modbus:data:tripower:SMA_Poll_Totaal:SMA_Totaal:number", widgetOrder = "6"}

Try to set length that correspond to what you want. That will say lenght = 12 on the first one and length = 1 on the second.
Are you sure that it is holding and not input register?

You are ysing blueplanet in .things and blueplane in .items

Thanks. A typo. I added the t and get some values. Now I can tune. Thanks again.