I am trying to make some lighting resilient to breaker trips. (I.e. You trip the breaker and the lights don't go out.)
Naturally it's all LED, and I am favorable toward low voltage DC lighting.
I want to have a DC always-positive and return bus (e.g. Red and black) then lighting wired in the usual way with a switch interrupting a switched-positive line to the light.
My question is — can I use multiple DC power supplies to feed this DC bus off multiple mains AC circuits? Idea being if an overload or GFCI trip knocks out a circuit, the other one keeps the lights on. Supplies would be oversized with that in mind.
Best Answer
I parallel power supplies all the time. The only problems I have found is with switching supplies sometimes they don't work well together but this is on loads that are inductive in nature. If I want to be 100% sure it will work I use a transformer based regulated supply set at the same voltage. So both supplies under normal load are being used. Setting 1 supply at a different level has the higher voltage one doing all the work and possibly failing earlier than if both are set at the same level. No diodes or anything else is needed. It is much like hooking 2 batteries in parallel for more amperage.