I use to cook on a GEN 1 MES smoker. I am very familiar with the problems associated with these units. Very hard to get smoke below 180*....it is a design flaw MES never corrected. But Someone has:
https://www.smokingmeatforums.com/threads/the-history-of-the-amnps-and-why-you-need-one.280090/
First, to get good smoke, the casings must be dry. You can either hang in front of a fan and blow ambient temp. air on the links to dry the casings, or put into the smoker with a little heat @100~120*.
When the casings are dry, introduce smoke. Smoke absorption occurs best while the surface of the casing stays below 140*. For this reason, I like to smoke my sausages for 2~3 hours or more @130* smoke chamber temperature. after this time period, the INT of the links will rise to about 104~109* at the highest. I now start bumping up the heat about 10* an hour trying to keep the chamber temperature roughly 25~30* above the sausage INT*. When I get to 170* chamber temp. I will hold this temp to finish the sausages *152* making sure the sausages stay @ 152* INT for a minimum of 12 minutes. This meets the USDA pasteurization chart standards. I will go to 154* when smoking wild hog though for insurance.
At this point, the links are done. They can be pulled, showered to cool and hung to bloom.
Time wise, it takes as long as it takes. The more sausage you smoke, the longer it will take- especially in a small unit like a MES. I know that in my GEN 1 MES, the max. pounds of sausage I could smoke effectively was 12.5 pounds. Any more than that and the smoke was uneven, the temps were uneven, the air flow was too restricted, and I would get fat out on the bottom 1/4 of the links. I use a ratio of pounds per cubic ft. of chamber space.
Using that same ratio, I know I can cook 120 pounds in my new smokehouse.
hope this helps.....