@wvmarle I checked for current on the wire for one of the limit switches with my clamp meter while the motor was running (and not) and the current was a maximum reading of 0.63 amps (see attached picture). I had the “Peak Hold” button set each time I ran the test. But please understand, that reading only happened once further away from the switch than most of the readings I took and it was near a wire connector someone put in that line for some reason (I bought the house with this GDO). I’m very suspicious about that reading because I tested it several times close to the limit switch and the typical amp draw was more like 0.10 to 0.20 amps or anywhere in between. Once I got 0.4x amps. It was actually varying quite a bit from test to test. My meter was set on 20 amps (see attached picture). My question for you is that since 0.100 amps is = 100ma I’m wondering if maybe it does have enough power after all, or could you have possibly been thinking in amps but instead wrote mA when you gave those numbers for current typically found on a switchs. What do you think? Could this wire run an optocoupler after all? If not, could I get power to the optocoupler another way and still use it for the signal?
Also for @wvmarle, regarding your post #9, I had come across this video that seems to support what you were saying about using only a diode on the limit switches, but the subtitles in the video are difficult for me to follow and it doesn’t seem to give “the whole story”. At 1:30 he mentions a diode connected to the limit switch. If you have about 2 minutes, watch this and give me your thoughts. My Genie looks to be almost exactly like this one (except with a black case). Sonoff TASMOTA garage remote limit switch hack - YouTube If a diode alone will work, how is it that the diagram @outsider provided would be modified? I’m confused on that.
@outsider, thanks for the diagram, and your “BTW” comment encouraged me to look closer at the wiring diagram I attached to post #3 from the owners manual (page 33). I didn’t see this until now, but it shows that the orange wire is the signal wire. That’s the bottom terminal in the picture I attached to post #7. Since that terminal measured 4.15 vdc as I mentioned in post #7, do you guys think that signal will be okay to connect to the Arduino directly? Seems logical to me.
@MorganS, thanks for the input. I won’t ignore your suggestions if my initial direction doesn’t pan out, but I just got excited when I realized that there are plenty of existing signals to do what I’d like to do already on the GDO and the other posts seem to be leading me in the “hopeful” direction. I may not be an electrical engineer, but I’m not afraid to screw something up, and I do realize that I need to seek advice from you guys before I attempt something like this. I will probably have everyone exhausted before I jump in, but I don’t mind asking questions as long as I don’t bother any of you too much in the process.