The Orion-Tr Smart doesn’t have a current limitation function, unfortunately - its settings and controls are based strictly on voltage, there is no adjustment of current. The Orion XS and XS 1400 do have current limitation available in the app, which is likely where you saw that.
I bought a Orion TR 12 - 12 - 9. The Input is connected to the vehicle while the Output ist connected to the Input of the 12/12 18a Smart Orion.
The Idea behind this solution is to us the small decive as a current limiter in oder to protect the smelt fuse (fuse behind the power socket for the Trailer hitch) and to use the smart Orion as a smart charger for my LiFePo
The Problem I am now facing is that the Output voltage of the small DC DC Konverter is reduced to approx. 8.2 and 8.3 V while charging (depending in the outputsettings. At the same time the Input voltage of the vehicle is approx. 13.5 V.
At the end the setup is working fine as the bigger DC DC coverter increases this far too low voltage back to the desired voltage.
Anyway - What worries me the most is the temperatur of the small DC DC Konverter plus a high tone while operating.
My question: Is my workaround a valid workaround or do I risk fire and smoke?
I would say you certainly risk letting out the magic smoke, most likely out of the Orion-Tr 12-12-9. That product is not designed to be used as you’re using it, and the Orion-Tr Smart on its output is certainly regularly trying to pull more than the Orion-Tr is capable of dealing with, which could certainly be anticipated to result in failure of one or both components.
I would suggest taking the Orion-Tr out of the circuit, and just properly wiring the Orion-Tr Smart with the larger-gauge wire and appropriate higher-amp fuse from the input battery.