Opto-Coupler Resistor Value

Author	Message
Amnesie Guru Joined: 30/06/2020 Location: Germany Posts: 763	Posted: 08:58am 10 May 2022       The resistor value is calculated like for any other LED; R= (Vin - ledVf) / Iled Example: R= (24v-1,5v)/ 0,04A = 562 Ohm, for the Power rating of the resistor: P= 0,04A^2*562 = 0,89W Greetings Daniel