Hi Guys
Looking for 4 channel optocoupler recommendations to handle 24V on the input in order to drive 5V on the collector emitter side.
Thanks
Typical opto isolator inputs are just an IR LED, you add the appropriate series resistor to limit the current.
Something like 2k2 would give 10mA drive.
So now we start a new thread when there was perfectly sound answer in this thread: 24V-36Volt on transistor Base - General Electronics - Arduino Forum
Use a resistive divider as explained in the other thread, that is the correct solution. There is zero reason to add an optocoupler to the circuit. You'll still need two resistors per channel with an opto so there is nothing to gain by doing this.
What about, in theory, the signal floating from 24-36v? would the voltage divider still be ok?
Yes, just include it in the calculation. Divide 36V back to 5V. 24V will be 24/36th of 5V = 3,33V which is well above the minimum to be a high.