Can PRTG monitor/read data from Datalogger (Tycon) ?

Hello,

if the device support SNMP, please ask the vendor about MIB files for your device. Those MIBs then can be imported as OIDLIBs in PRTG: https://www.paessler.com/tools/mibimporter

In order to use those, please add the SNMP Library sensor, during sensor creation then select the OIDLIB: https://www.paessler.com/manuals/prtg/snmp_library_sensor

Without SNMP support, please check if the device offers something through HTTP. Access would then be more different, as you probably have to do the web request yourself, for example through Powershell's invoke-webrequest command, in a Exe/Script Advanced sensor: https://www.paessler.com/manuals/prtg/exe_script_advanced_sensor