Just realizing you added more details to your post, thanks this helps.
Do the LED indicators for each zone stay on even when the zone is off? As I understand things they would not?
I know that this situation is possible:
Each zone has an inline fuse protecting it from the valve. Before the fuse, a LED indicator is wired so that it only comes on when the fuse blows (a resistor in series to LED that is parallel to the fuse I believe).
I am wondering if this situation is possible:
Instead of individual LEDs, would it be possible to have all zones connected to a shared relay, before their fuse, that would only ever be turned on if one of the fuses blows on a zone? It would only need to trigger another circuit to power on and then it could turn off (when the zone turns off per its schedule). Would this be a shared relay that gets powered on only when a fuse is blown? It would change the state of another circuit which would need to stay powered on even after the relay turns off again. Some reset “button” would be needed I suppose. This way I can have a large visible indicator light outside the box or an alarm that stays on.
Anyone else have experience adding on circuit protection and alerting to our controllers?