Tested the amperage draw yesterday, when a relay input is pulled to low, there is ~70 ma draw per activated relay across the JD-VCC power (the pic shows 130 ma with 2 relays activated).
Wired it up, and works fine and dandy so far. For my use case, only 1 relay will be activated at a time, so connecting JDVCC on the relay board to pin2 (5V) on the Pi is working just great.
When the Pi boots up, it looks like the Pi defaults to trying to turn on relays 1-7 (but not 8), but none of the relays click - I’m guessing there is not sufficient power. Once my app starts, it brings all pins to high and all is well. I have pin0 wired to relay1, and so on.
I’m using pi4j based on a cursory scan of the interwebs (Java guys are reluctant to learn phyton), is that the best option for Java?