Originally Posted by Al_The_Man
1) What is the purpose of the light? work light or indicator? As alternate source could be used depending on purpose
2) You could keep both at 12v
3) ONLY use a diode on DC relays, it is for back emf suppression, on AC relays a resistance/capacitance snubber should be used.
4) The 15amp rating is probabally resistive load, when breaking a heavy DC inductive current, contact arcing and welding can occur, it is often better to break the AC side at the same time, use a multi-pole relay and disable the drives at the same time, if they have an enable input.
5)Depending on the VA of the transformer, I would expect 5amps max.
6) could'nt make that one out on the drawing
Note: Relays that break a heavy DC inductive load are fitted with magnets close to the contacts, called arc blow-out relays.
Al.