That should prevent the issue you described...for what it's worth, I'm looking at my hand-drawn sketch of the same thing, only diff is I used 1N4001 (1.0 Amp) diodes, was going to make it look nice and post it but you're on it, man!
Thanks mate. I really hope this solves all my problems. A 1N4001 would probably be better. I just grabbed a 1N4004 because i already have a few. I have ordered 4 new cameras so i can test this setup on the bench before i head back to the job site to fix the issues.That should prevent the issue you described...for what it's worth, I'm looking at my hand-drawn sketch of the same thing, only diff is I used 1N4001 (1.0 Amp) diodes, was going to make it look nice and post it but you're on it, man!
Basically, the steering diodes create a n-input 'OR' gate (negative logic, low true) to drive the relay coil.
I've removed the superfluous content from my posts to this thread.
Using isolation diodes to OR the signals will likely fix the problem regardless of whether the outputs are "open collector" or "push pull". So I can't see why this won't work just great!
The 1N4004s are fine. The only difference in the specifications is the maximum reverse voltage rating. Having a "too high" max reverse voltage won't hurt a thing. And they cost almost exactly the same, at least in reasonable quantities from most vendors. So if I'm keeping a bunch of general purpose 1A diodes on hand, why not get the ones with the higher breakdown voltage?