This is the process that I use for smoked sausages, not fresh sausages.
Hour 1 smoker at 130° no smoke. This helps dry the sausages
Hour 2 bump temp to 140° add smoke
Hour 3. bump temp to 150° continue smoke
Hour 4 bump temp to 160° continue smoke
Hour 5 bump temp to 170° continue smoke
I will leave it a that temp until the sausages hit 156°-160° IT. The overall process can take 8-12 hours depending on the style of sausage and how much is in the smoker. Using higher heat like you suggest will lead to fat out and greasy sausage. temps need to be kept below 180°
For fresh sausages it depends on the style but I grill most of mine over high heat or if breakfast sausages over medium heat in the cast iron.