Post by howie on Jun 23, 2024 5:34:13 GMT -5
I am creating a app for my iphone to monitor/control a older non-wifi able Generac generator. To do this, I'm using Crestron IO sensors to detect contact closure. The control board on the generator has 7 LED's that describe it's state and provide diagnostics. Each LED has 1.94 vdc all the time and the ground is switched to them to turn them on. I want to tap this voltage and ground at each LED and input to a PC817 optocoupler chip. However, the maximum input voltage for the 817 is 1.4 vdc. Typical voltage for the chip to trigger is 1.2 vdc. My thought is to put a X ohm resister on the + input of the 817 and use the output to show contact closure and just shrink wrap it into the cable. Not sure if my math is right but would a standard 33 ohm resistor work? If not what would?
