This is my first post here, so sorry if I am messing up something. I tried to find a similar post but could not find it. Also, I am new in the Arduino world and a newbie with eletronics.
So, this is my problem: I have a 12V single relay with optocoupler (at least it looks like an optocoupler) that I want to connect an external power supply to separate a solenoid valve, that I am trying to control, from the Arduino's circuit. But I am not sure how to connect the external power supply, or if I can at all.
My relay looks like this one but 12V:
I have seen in other relays something like JVcc (or something like that) where you are supposed to connect your external power supply to make use of the optocoupler, or you can leave the jumper in the pins to use the Arduino as a power source to the relay but without the optocoupler isolation.
Mine has also those 3 pins with jumpers, but they are labelled as H/L (see image). My question is: Can I connect my external power supply to these H/L pins to make you of the optocoupler or this is completely wrong?
Sorry for the long post and thank you guys in advance,