Stephen, Hi. I am new to this forum, and Fred and the other folks are really sharp. Welcome. I wouldn’t say you are “only” an electrician. I have been an industrial controls electrician for over 20 years and good ones are hard to come by. Plus, I learned PLC programming and troubleshooting with ladder logic on my own, through intellectual property theft (haha), online reading, books, practical experience and the good grace and kindness of others willing to teach me. I love programming because I’m in the office a lot now (getting older) and I still do my own start-ups and De-bugging on my projects.
Anyway, welcome and as to your post, a timer wouldn’t necessarily be the best way to activate an OTU, maybe you could put an equal (EQU) instruction in the rung to unlatch it. Have a great week.