Very observant and thorough reading of the instructions. However, it doesn't actually state which direction it must go. Essentially it is just a spring-loaded lever with a micro switch that if there is slack it closes the switch. It does state the location of the roller is to be 2"-6" from the drum which even in the diagram is more like 10". The sensor itself is 4" so it would be physically impossible in this application due to track radius and in most applications with anything bigger than a 400-8 drum. On a door such as this with no high lift, it would hit the door as it came through the radius if it were flipped over. The manual doesn't show a real door application, it's a drawing that is not even to scale and unfortunately the engineers probably never actually installed one on a standard lift door. I even noticed on the newest Chamberlain literature promoting this opener they installed it on a door that is low headroom with a reverse wind spring system which is literally the second thing in the owners manual. This opener can't be switched to reverse. This would cause the opener to close if something triggered the safety eyes instead of opening. Sometimes the instructions and literature aren't a good reference for the real world. We have installed hunderds if not thousands of these style openers going back to the 3800 series and have mounted the tensioner either way to suit the application and never once has this caused an issue.
Your cable tension monitor is on upside down. 😂😂 per manual page 10 👍🏻
Very observant and thorough reading of the instructions. However, it doesn't actually state which direction it must go. Essentially it is just a spring-loaded lever with a micro switch that if there is slack it closes the switch. It does state the location of the roller is to be 2"-6" from the drum which even in the diagram is more like 10". The sensor itself is 4" so it would be physically impossible in this application due to track radius and in most applications with anything bigger than a 400-8 drum. On a door such as this with no high lift, it would hit the door as it came through the radius if it were flipped over. The manual doesn't show a real door application, it's a drawing that is not even to scale and unfortunately the engineers probably never actually installed one on a standard lift door. I even noticed on the newest Chamberlain literature promoting this opener they installed it on a door that is low headroom with a reverse wind spring system which is literally the second thing in the owners manual. This opener can't be switched to reverse. This would cause the opener to close if something triggered the safety eyes instead of opening. Sometimes the instructions and literature aren't a good reference for the real world. We have installed hunderds if not thousands of these style openers going back to the 3800 series and have mounted the tensioner either way to suit the application and never once has this caused an issue.